SMSC LAN9303M/LAN9303Mi DATASHEET Revision 1.5 (07-08-11)
Datasheet
PRODUCT FEATURES
LAN9303M/LAN9303Mi
Small Form Factor Three Port
10/100 Managed Ethernet Switch
with Dual MII/RMII/Turbo MII
Highlights
Up to 200Mbps via Turbo MII Interface
2nd MII/RMII/Turbo MII interface allows connection to
an external MOCA, HomePNA, HomePlug,
cable/DSL modem module or 2nd SOC with speeds
up to 200Mbps
High performance, full featured 3 port switch with
VLAN, QoS packet prioritization, Rate Limiting, IGMP
monitoring and management functions
Serial management via I2C or SMI
Unique Virtual PHY feature simplifies software
development by mimicking the multiple switch ports
as a single port PHY
Target Applications
Cable, satellite, and IP set-top boxes
Digital televisions
Digital video recorders
VoIP/Video phone systems
Home gateways
Test/Measurement equipment
Industrial automation systems
Key Benefits
Ethernet Switch Fabric
32K buffer RAM
512 entry forwarding table
Port based IEEE 802.1Q VLAN support (16 groups)
Programmable IEEE 802.1Q tag insertion/removal
IEEE 802.1D spanning tree protocol support
4 separate transmit queues available per port
Fixed or weighted egress priority servicing
QoS/CoS Packet prioritization
Input priority determined by VLAN tag, DA lookup,
TOS, DIFFSERV or port default value
Programmable Traffic Class map based on input
priority on per port basis
Remapping of 802.1Q priority field on per port basis
Programmable rate limiting at the ingress with
coloring and random early discard, per port / priority
Programmable rate limiting at the egress with leaky
bucket algorithm, per port / priority
IGMP v1/v2/v3 monitoring for Multicast packet filtering
Programmable broadcast storm protection with global
% control and enable per port
Programmable buffer usage limits
Dynamic queues on internal memory
Programmable filter by MAC address
Switch Management
Port mirroring/monitoring/sniffing: ingress and/or egress
traffic on any port or port pair
Fully compliant statistics (MIB) gathering counters
Control registers configurable on-the-fly
Ports
Port 0 - MII MAC, MII PHY, RMII PHY modes
Port 1 - MII MAC, MII PHY, RMII PHY mode options
2 internal 10/100 PHYs with HP Auto-MDIX support
200Mbps Turbo MII (PHY or MAC mode)
Fully compliant with IEEE 802.3 standards
10BASE-T and 100BASE-TX support
Full and half duplex support
Full duplex flow control
Backpressure (forced collision) half duplex flow control
Automatic flow control based on programmable levels
Automatic 32-bit CRC generation and checking
2K Jumbo packet support
Programmable interframe gap, flow control pause value
Full transmit/receive statistics
Full LED support per port
Auto-negotiation
Automatic polarity correction
Automatic MDI/MDI-X
Loop-back mode
Serial Management
—I
2C (slave) access to all internal registers
MIIM (MDIO) access to PHY related registers
SMI (extended MIIM) access to all internal registers
Other Features
General Purpose Timer
—I
2C Serial EEPROM interface
Programmable GPIOs/LEDs
Single 3.3V power supply
ESD Protection Levels
±8kV HBM without External Protection Devices
±8kV contact mode (IEC61000-4-2)
±15kV air-gap discharge mode (IEC61000-4-2)
Latch-up exceeds ±150mA per EIA/JESD 78
72-pin QFN (10x10 mm) Lead-Free RoHS Compliant
Package
Available in Commercial & Industrial Temp. Ranges
Order Number(s):
LAN9303M-AKZE for 72-Pin, QFN Lead-Free RoHS Compliant Package (0 to 70°C Temp Range)
LAN9303Mi-AKZE for 72-Pin, QFN Lead-Free RoHS Compliant Package (-40 to 85°C Temp Range)
This product meets the halogen maximum concentration values per IEC61249-2-21
For RoHS compliance and environmental information, please visit www.smsc.com/rohs
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 2 SMSC LAN9303M/LAN9303Mi
DATASHEET
80 ARKAY DRIVE, HAUPPAUGE, NY 11788 (631) 435-6000 or 1 (800) 443-SEMI
Copyright © 2011 SMSC or its subsidiaries. All rights reserved.
Circuit diagrams and other information relating to SMSC products are included as a means of illustrating typical applications. Consequently, complete information sufficient for
construction purposes is not necessarily given. Although the information has been checked and is believed to be accurate, no responsibility is assumed for inaccuracies. SMSC
reserves the right to make changes to specifications and product descriptions at any time without notice. Contact your local SMSC sales office to obtain the latest specifications
before placing your product order. The provision of this information does not convey to the purchaser of the described semiconductor devices any licenses under any patent
rights or other intellectual property rights of SMSC or others. All sales are expressly conditional on your agreement to the terms and conditions of the most recently dated
version of SMSC's standard Terms of Sale Agreement dated before the date of your order (the "Terms of Sale Agreement"). The product may contain design defects or errors
known as anomalies which may cause the product's functions to deviate from published specifications. Anomaly sheets are available upon request. SMSC products are not
designed, intended, authorized or warranted for use in any life support or other application where product failure could cause or contribute to personal injury or severe property
damage. Any and all such uses without prior written approval of an Officer of SMSC and further testing and/or modification will be fully at the risk of the customer. Copies of
this document or other SMSC literature, as well as the Terms of Sale Agreement, may be obtained by visiting SMSC’s website at http://www.smsc.com. SMSC is a registered
trademark of Standard Microsystems Corporation (“SMSC”). Product names and company names are the trademarks of their respective holders.
SMSC DISCLAIMS AND EXCLUDES ANY AND ALL WARRANTIES, INCLUDING WITHOUT LIMITATION ANY AND ALL IMPLIED WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE, TITLE, AND AGAINST INFRINGEMENT AND THE LIKE, AND ANY AND ALL WARRANTIES ARISING FROM ANY COURSE
OF DEALING OR USAGE OF TRADE. IN NO EVENT SHALL SMSC BE LIABLE FOR ANY DIRECT, INCIDENTAL, INDIRECT, SPECIAL, PUNITIVE, OR CONSEQUENTIAL
DAMAGES; OR FOR LOST DATA, PROFITS, SAVINGS OR REVENUES OF ANY KIND; REGARDLESS OF THE FORM OF ACTION, WHETHER BASED ON CONTRACT;
TORT; NEGLIGENCE OF SMSC OR OTHERS; STRICT LIABILITY; BREACH OF WARRANTY; OR OTHERWISE; WHETHER OR NOT ANY REMEDY OF BUYER IS HELD
TO HAVE FAILED OF ITS ESSENTIAL PURPOSE, AND WHETHER OR NOT SMSC HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 3 Revision 1.5 (07-08-11)
DATASHEET
Table of Contents
Chapter 1 Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.1 General Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Chapter 2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.1 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.2 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.2.1 System Clocks/Reset/PME Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.2.2 System Interrupt Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.2.3 Switch Fabric . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.2.4 Ethernet PHYs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.2.5 PHY Management Interface (PMI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.2.6 I2C Slave Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.2.7 SMI Slave Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.2.8 EEPROM Controller/Loader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.2.9 GPIO/LED Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.3 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.3.1 Internal PHY Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.3.2 MAC Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.3.3 PHY Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.3.4 Management Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Chapter 3 Pin Description and Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.1 Pin Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.1.1 72-QFN Pin Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.2 Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
3.3 Buffer Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Chapter 4 Clocking, Resets, and Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
4.1 Clocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
4.2 Resets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
4.2.1 Chip-Level Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
4.2.1.1 Power-On Reset (POR) .................................................................................................................................................................................. 49
4.2.1.2 nRST Pin Reset .............................................................................................................................................................................................. 49
4.2.2 Multi-Module Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
4.2.2.1 Digital Reset (DIGITAL_RST) ......................................................................................................................................................................... 50
4.2.3 Single-Module Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
4.2.3.1 Port 2 PHY Reset............................................................................................................................................................................................ 50
4.2.3.2 Port 1 PHY Reset............................................................................................................................................................................................ 51
4.2.3.3 Virtual PHY Reset ........................................................................................................................................................................................... 51
4.2.4 Configuration Straps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
4.2.4.1 Soft-Straps ...................................................................................................................................................................................................... 52
4.2.4.2 Hard-Straps..................................................................................................................................................................................................... 59
4.3 Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
4.3.1 Port 1 & 2 PHY Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Chapter 5 System Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
5.1 Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
5.2 Interrupt Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
5.2.1 Switch Fabric Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
5.2.2 Ethernet PHY Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
5.2.3 GPIO Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
5.2.4 General Purpose Timer Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 4 SMSC LAN9303M/LAN9303Mi
DATASHEET
5.2.5 Software Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
5.2.6 Device Ready Interrupt. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Chapter 6 Switch Fabric . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
6.1 Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
6.2 Switch Fabric CSRs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
6.2.1 Switch Fabric CSR Writes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
6.2.2 Switch Fabric CSR Reads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
6.2.3 Flow Control Enable Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
6.3 10/100 Ethernet MACs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
6.3.1 Receive MAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
6.3.1.1 Receive Counters ........................................................................................................................................................................................... 73
6.3.2 Transmit MAC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
6.3.2.1 Transmit Counters .......................................................................................................................................................................................... 74
6.4 Switch Engine (SWE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
6.4.1 MAC Address Lookup Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
6.4.1.1 Learning/Aging/Migration ................................................................................................................................................................................ 76
6.4.1.2 Static Entries................................................................................................................................................................................................... 76
6.4.1.3 Multicast Pruning ............................................................................................................................................................................................ 76
6.4.1.4 Address Filtering ............................................................................................................................................................................................. 76
6.4.1.5 Spanning Tree Port State Override................................................................................................................................................................. 76
6.4.1.6 MAC Destination Address Lookup Priority...................................................................................................................................................... 76
6.4.1.7 Host Access .................................................................................................................................................................................................... 76
6.4.2 Forwarding Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
6.4.3 Transmit Priority Queue Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
6.4.3.1 Port Default Priority......................................................................................................................................................................................... 81
6.4.3.2 IP Precedence Based Priority......................................................................................................................................................................... 81
6.4.3.3 DIFFSERV Based Priority............................................................................................................................................................................... 81
6.4.3.4 VLAN Priority .................................................................................................................................................................................................. 81
6.4.4 VLAN Support. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
6.4.5 Spanning Tree Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
6.4.6 Ingress Flow Metering and Coloring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
6.4.6.1 Ingress Flow Calculation................................................................................................................................................................................. 85
6.4.7 Broadcast Storm Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
6.4.8 IPv4 IGMP Support. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
6.4.9 Port Mirroring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
6.4.10 Host CPU Port Special Tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
6.4.10.1 Packets from the Host CPU ............................................................................................................................................................................ 88
6.4.10.2 Packets to the Host CPU ................................................................................................................................................................................ 89
6.4.11 Counters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
6.5 Buffer Manager (BM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
6.5.1 Packet Buffer Allocation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
6.5.1.1 Buffer Limits and Flow Control Levels ............................................................................................................................................................ 90
6.5.2 Random Early Discard (RED). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
6.5.3 Transmit Queues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
6.5.4 Transmit Priority Queue Servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
6.5.5 Egress Rate Limiting (Leaky Bucket) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
6.5.6 Adding, Removing, and Changing VLAN Tags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
6.5.7 Counters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
6.6 Switch Fabric Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Chapter 7 Ethernet PHYs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
7.1 Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
7.1.1 PHY Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
7.2 Port 1 & 2 PHYs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
7.2.1 100BASE-TX Transmit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
7.2.1.1 MII MAC Interface ........................................................................................................................................................................................... 98
7.2.1.2 4B/5B Encoder................................................................................................................................................................................................ 98
7.2.1.3 Scrambler and PISO..................................................................................................................................................................................... 100
7.2.1.4 NRZI and MLT-3 Encoding ........................................................................................................................................................................... 100
7.2.1.5 100M Transmit Driver ................................................................................................................................................................................... 100
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 5 Revision 1.5 (07-08-11)
DATASHEET
7.2.1.6 100M Phase Lock Loop (PLL) ...................................................................................................................................................................... 100
7.2.2 100BASE-TX Receive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
7.2.2.1 A/D Converter ............................................................................................................................................................................................... 101
7.2.2.2 DSP: Equalizer, BLW Correction and Clock/Data Recovery ........................................................................................................................ 101
7.2.2.3 NRZI and MLT-3 Decoding........................................................................................................................................................................... 102
7.2.2.4 Descrambler and SIPO ................................................................................................................................................................................. 102
7.2.2.5 5B/4B Decoding ............................................................................................................................................................................................ 102
7.2.2.6 Receiver Errors ............................................................................................................................................................................................. 102
7.2.2.7 MII MAC Interface ......................................................................................................................................................................................... 102
7.2.3 10BASE-T Transmit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
7.2.3.1 MII MAC Interface ......................................................................................................................................................................................... 103
7.2.3.2 10M TX Driver and PLL ................................................................................................................................................................................ 103
7.2.4 10BASE-T Receive. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
7.2.4.1 Filter and Squelch ......................................................................................................................................................................................... 103
7.2.4.2 10M RX and PLL........................................................................................................................................................................................... 103
7.2.4.3 MII MAC Interface ......................................................................................................................................................................................... 104
7.2.4.4 Jabber Detection........................................................................................................................................................................................... 104
7.2.5 PHY Auto-negotiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
7.2.5.1 PHY Pause Flow Control .............................................................................................................................................................................. 106
7.2.5.2 Parallel Detection.......................................................................................................................................................................................... 106
7.2.5.3 Restarting Auto-Negotiation.......................................................................................................................................................................... 106
7.2.5.4 Disabling Auto-Negotiation ........................................................................................................................................................................... 106
7.2.5.5 Half Vs. Full-Duplex ...................................................................................................................................................................................... 107
7.2.6 HP Auto-MDIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
7.2.7 MII MAC Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
7.2.8 PHY Management Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
7.2.8.1 PHY Interrupts .............................................................................................................................................................................................. 108
7.2.9 PHY Power-Down Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
7.2.9.1 PHY General Power-Down ........................................................................................................................................................................... 109
7.2.9.2 PHY Energy Detect Power-Down ................................................................................................................................................................. 109
7.2.10 PHY Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
7.2.10.1 PHY Software Reset via RESET_CTL.......................................................................................................................................................... 110
7.2.10.2 PHY Software Reset via PHY_BASIC_CTRL_x ........................................................................................................................................... 110
7.2.10.3 PHY Power-Down Reset............................................................................................................................................................................... 110
7.2.11 LEDs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
7.2.12 Required Ethernet Magnetics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
7.3 Virtual PHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
7.3.1 Virtual PHY Auto-Negotiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
7.3.1.1 Parallel Detection.......................................................................................................................................................................................... 112
7.3.1.2 Disabling Auto-Negotiation ........................................................................................................................................................................... 112
7.3.1.3 Virtual PHY Pause Flow Control ................................................................................................................................................................... 112
7.3.2 Virtual PHY in MAC Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
7.3.2.1 Full-Duplex Flow Control............................................................................................................................................................................... 113
7.3.3 Virtual PHY Resets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
7.3.3.1 Virtual PHY Software Reset via RESET_CTL .............................................................................................................................................. 113
7.3.3.2 Virtual PHY Software Reset via VPHY_BASIC_CTRL ................................................................................................................................. 113
Chapter 8 Serial Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
8.1 Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
8.2 I2C Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
8.3 I2C Master EEPROM Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
8.3.1 I2C EEPROM Device Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
8.3.2 I2C EEPROM Byte Read . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
8.3.3 I2C EEPROM Sequential Byte Reads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
8.3.4 I2C EEPROM Byte Writes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
8.3.5 Wait State Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
8.3.6 I2C Bus Arbitration and Clock Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
8.3.6.1 Bus Busy....................................................................................................................................................................................................... 118
8.3.6.2 Clock Synchronization .................................................................................................................................................................................. 118
8.3.6.3 Arbitration...................................................................................................................................................................................................... 119
8.3.6.4 Timeout Due to Busy or Arbitration............................................................................................................................................................... 119
8.3.7 I2C Master EEPROM Controller Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
8.4 EEPROM Loader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
8.4.1 EEPROM Loader Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
8.4.2 EEPROM Valid Flag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 6 SMSC LAN9303M/LAN9303Mi
DATASHEET
8.4.3 MAC Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
8.4.4 Soft-Straps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
8.4.4.1 PHY Registers Synchronization.................................................................................................................................................................... 123
8.4.4.2 Virtual PHY Registers Synchronization......................................................................................................................................................... 124
8.4.4.3 Port 1 MII Basic Control Register Synchronization ....................................................................................................................................... 124
8.4.4.4 LED and Manual Flow Control Register Synchronization............................................................................................................................. 124
8.4.5 Register Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
8.4.6 EEPROM Loader Finished Wait-State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
8.4.7 Reset Sequence and EEPROM Loader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
8.5 I2C Slave Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
8.5.1 I2C Slave Command Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
8.5.2 I2C Slave Read Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
8.5.2.1 I2C Slave Read Polling for Reset Complete ................................................................................................................................................. 127
8.5.3 I2C Slave Write Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Chapter 9 MII Data Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
9.1 Port 0 MII Data Path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
9.1.1 Port 0 MII MAC Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
9.1.2 Port 0 MII PHY Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
9.1.2.1 Turbo Operation............................................................................................................................................................................................ 129
9.1.2.2 Clock Drive Strength ..................................................................................................................................................................................... 129
9.1.2.3 Signal Quality Error (SQE) Heartbeat Test ................................................................................................................................................... 129
9.1.2.4 Collision Test ................................................................................................................................................................................................ 130
9.1.2.5 Loopback ...................................................................................................................................................................................................... 130
9.1.3 Port 0 RMII PHY Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
9.1.3.1 Reference Clock Selection............................................................................................................................................................................ 130
9.1.3.2 Clock Drive Strength ..................................................................................................................................................................................... 131
9.1.3.3 Signal Quality Error (SQE) Heartbeat Test ................................................................................................................................................... 131
9.1.3.4 Collision Test ................................................................................................................................................................................................ 131
9.1.3.5 Loopback Mode ............................................................................................................................................................................................ 131
9.2 Port 1 MII MUX/Data Path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
9.2.1 Port 1 Internal Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
9.2.2 Port 1 MII MAC Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
9.2.3 Port 1 MII PHY Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
9.2.3.1 Turbo Operation............................................................................................................................................................................................ 132
9.2.3.2 Clock Drive Strength ..................................................................................................................................................................................... 132
9.2.3.3 Signal Quality Error (SQE) Heartbeat Test ................................................................................................................................................... 132
9.2.3.4 Collision Test ................................................................................................................................................................................................ 132
9.2.3.5 Loopback ...................................................................................................................................................................................................... 133
9.2.4 Port 1 RMII PHY Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
9.2.4.1 Reference Clock Selection............................................................................................................................................................................ 133
9.2.4.2 Clock Drive Strength ..................................................................................................................................................................................... 133
9.2.4.3 Signal Quality Error (SQE) Heartbeat Test ................................................................................................................................................... 133
9.2.4.4 Collision Test ................................................................................................................................................................................................ 134
9.2.4.5 Loopback Mode ............................................................................................................................................................................................ 134
Chapter 10 MII Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
10.1 Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
10.2 SMI Slave Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
10.2.1 Read Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
10.2.1.1 SMI Read Polling for Reset Complete .......................................................................................................................................................... 137
10.2.2 Write Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
10.3 PHY Management Interface (PMI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
10.3.1 EEPROM Loader PHY Register Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
10.4 MII Mode Multiplexer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
10.4.1 Port 0 MAC Mode SMI Managed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
10.4.2 Port 0 MAC Mode I2C Managed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
10.4.3 Port 0 PHY Mode SMI Managed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
10.4.4 Port 0 PHY Mode I2C Managed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
Chapter 11 General Purpose Timer & Free-Running Clock. . . . . . . . . . . . . . . . . . . . . . . . 143
11.1 General Purpose Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 7 Revision 1.5 (07-08-11)
DATASHEET
11.2 Free-Running Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Chapter 12 GPIO/LED Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
12.1 Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
12.2 GPIO Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
12.2.1 GPIO Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
12.2.1.1 GPIO Interrupt Polarity.................................................................................................................................................................................. 145
12.3 LED Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
12.3.1 LED Function Definitions when LED_FUN[1:0] = 00b, 01b, or 10b . . . . . . . . . . . . . . . . . . . . . . 146
12.3.2 LED Function Definitions when LED_FUN[1:0] = 11b . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
Chapter 13 Register Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
13.1 Register Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
13.2 System Control and Status Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
13.2.1 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
13.2.1.1 Interrupt Configuration Register (IRQ_CFG) ................................................................................................................................................ 152
13.2.1.2 Interrupt Status Register (INT_STS)............................................................................................................................................................. 154
13.2.1.3 Interrupt Enable Register (INT_EN).............................................................................................................................................................. 155
13.2.2 GPIO/LED. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
13.2.2.1 General Purpose I/O Configuration Register (GPIO_CFG) .......................................................................................................................... 156
13.2.2.2 General Purpose I/O Data & Direction Register (GPIO_DATA_DIR) ........................................................................................................... 157
13.2.2.3 General Purpose I/O Interrupt Status and Enable Register (GPIO_INT_STS_EN)...................................................................................... 158
13.2.2.4 LED Configuration Register (LED_CFG) ...................................................................................................................................................... 159
13.2.3 EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
13.2.3.1 EEPROM Command Register (E2P_CMD).................................................................................................................................................. 160
13.2.3.2 EEPROM Data Register (E2P_DATA).......................................................................................................................................................... 163
13.2.4 Switch Fabric . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
13.2.4.1 Port 1 Manual Flow Control Register (MANUAL_FC_1)............................................................................................................................... 164
13.2.4.2 Port 2 Manual Flow Control Register (MANUAL_FC_2)............................................................................................................................... 166
13.2.4.3 Port 0 Manual Flow Control Register (MANUAL_FC_0)............................................................................................................................... 168
13.2.4.4 Switch Fabric CSR Interface Data Register (SWITCH_CSR_DATA) ........................................................................................................... 170
13.2.4.5 Switch Fabric CSR Interface Command Register (SWITCH_CSR_CMD) ................................................................................................... 171
13.2.4.6 Switch Fabric MAC Address High Register (SWITCH_MAC_ADDRH) ........................................................................................................ 173
13.2.4.7 Switch Fabric MAC Address Low Register (SWITCH_MAC_ADDRL) ......................................................................................................... 174
13.2.4.8 Switch Fabric CSR Interface Direct Data Registers (SWITCH_CSR_DIRECT_DATA) ............................................................................... 176
13.2.5 PHY Management Interface (PMI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
13.2.5.1 PHY Management Interface Data Register (PMI_DATA) ............................................................................................................................. 179
13.2.5.2 PHY Management Interface Access Register (PMI_ACCESS).................................................................................................................... 180
13.2.6 Virtual PHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
13.2.6.1 Virtual PHY Basic Control Register (VPHY_BASIC_CTRL) ......................................................................................................................... 182
13.2.6.2 Virtual PHY Basic Status Register (VPHY_BASIC_STATUS)...................................................................................................................... 184
13.2.6.3 Virtual PHY Identification MSB Register (VPHY_ID_MSB) .......................................................................................................................... 186
13.2.6.4 Virtual PHY Identification LSB Register (VPHY_ID_LSB) ............................................................................................................................ 187
13.2.6.5 Virtual PHY Auto-Negotiation Advertisement Register (VPHY_AN_ADV).................................................................................................... 188
13.2.6.6 Virtual PHY Auto-Negotiation Link Partner Base Page Ability Register (VPHY_AN_LP_BASE_ABILITY).................................................. 190
13.2.6.7 Virtual PHY Auto-Negotiation Expansion Register (VPHY_AN_EXP) .......................................................................................................... 193
13.2.6.8 Virtual PHY Special Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS) .............................................................................. 194
13.2.7 Miscellaneous. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
13.2.7.1 Chip ID and Revision (ID_REV).................................................................................................................................................................... 196
13.2.7.2 Byte Order Test Register (BYTE_TEST) ...................................................................................................................................................... 197
13.2.7.3 Hardware Configuration Register (HW_CFG)............................................................................................................................................... 198
13.2.7.4 General Purpose Timer Configuration Register (GPT_CFG) ....................................................................................................................... 199
13.2.7.5 General Purpose Timer Count Register (GPT_CNT) ................................................................................................................................... 200
13.2.7.6 Free Running 25MHz Counter Register (FREE_RUN)................................................................................................................................. 201
13.2.7.7 Port 1 MII Basic Control Register (P1_MII_BASIC_CONTROL) .................................................................................................................. 202
13.2.7.8 Reset Control Register (RESET_CTL) ......................................................................................................................................................... 205
13.3 Ethernet PHY Control and Status Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
13.3.1 Virtual PHY Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
13.3.2 Port 1 & 2 PHY Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
13.3.2.1 Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x) ................................................................................................................ 208
13.3.2.2 Port x PHY Basic Status Register (PHY_BASIC_STATUS_x) ..................................................................................................................... 210
13.3.2.3 Port x PHY Identification MSB Register (PHY_ID_MSB_x).......................................................................................................................... 212
13.3.2.4 Port x PHY Identification LSB Register (PHY_ID_LSB_x)............................................................................................................................ 213
13.3.2.5 Port x PHY Auto-Negotiation Advertisement Register (PHY_AN_ADV_x)................................................................................................... 214
13.3.2.6 Port x PHY Auto-Negotiation Link Partner Base Page Ability Register (PHY_AN_LP_BASE_ABILITY_x) ................................................. 217
13.3.2.7 Port x PHY Auto-Negotiation Expansion Register (PHY_AN_EXP_x) ......................................................................................................... 219
13.3.2.8 Port x PHY Mode Control/Status Register (PHY_MODE_CONTROL_STATUS_x)..................................................................................... 220
13.3.2.9 Port x PHY Special Modes Register (PHY_SPECIAL_MODES_x) .............................................................................................................. 221
13.3.2.10 Port x PHY Special Control/Status Indication Register (PHY_SPECIAL_CONTROL_STAT_IND_x) .......................................................... 223
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 8 SMSC LAN9303M/LAN9303Mi
DATASHEET
13.3.2.11 Port x PHY Interrupt Source Flags Register (PHY_INTERRUPT_SOURCE_x)........................................................................................... 225
13.3.2.12 Port x PHY Interrupt Mask Register (PHY_INTERRUPT_MASK_x) ............................................................................................................ 226
13.3.2.13 Port x PHY Special Control/Status Register (PHY_SPECIAL_CONTROL_STATUS_x).............................................................................. 227
13.4 Switch Fabric Control and Status Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
13.4.1 General Switch CSRs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
13.4.1.1 Switch Device ID Register (SW_DEV_ID) .................................................................................................................................................... 239
13.4.1.2 Switch Reset Register (SW_RESET) ........................................................................................................................................................... 240
13.4.1.3 Switch Global Interrupt Mask Register (SW_IMR)........................................................................................................................................ 241
13.4.1.4 Switch Global Interrupt Pending Register (SW_IPR).................................................................................................................................... 242
13.4.2 Switch Port 0, Port 1, and Port 2 CSRs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
13.4.2.1 Port x MAC Version ID Register (MAC_VER_ID_x) ..................................................................................................................................... 243
13.4.2.2 Port x MAC Receive Configuration Register (MAC_RX_CFG_x) ................................................................................................................. 244
13.4.2.3 Port x MAC Receive Undersize Count Register (MAC_RX_UNDSZE_CNT_x)........................................................................................... 245
13.4.2.4 Port x MAC Receive 64 Byte Count Register (MAC_RX_64_CNT_x).......................................................................................................... 246
13.4.2.5 Port x MAC Receive 65 to 127 Byte Count Register (MAC_RX_65_TO_127_CNT_x)................................................................................ 247
13.4.2.6 Port x MAC Receive 128 to 255 Byte Count Register (MAC_RX_128_TO_255_CNT_x)............................................................................ 248
13.4.2.7 Port x MAC Receive 256 to 511 Byte Count Register (MAC_RX_256_TO_511_CNT_x)............................................................................ 249
13.4.2.8 Port x MAC Receive 512 to 1023 Byte Count Register (MAC_RX_512_TO_1023_CNT_x)........................................................................ 250
13.4.2.9 Port x MAC Receive 1024 to Max Byte Count Register (MAC_RX_1024_TO_MAX_CNT_x) ..................................................................... 251
13.4.2.10 Port x MAC Receive Oversize Count Register (MAC_RX_OVRSZE_CNT_x)............................................................................................. 252
13.4.2.11 Port x MAC Receive OK Count Register (MAC_RX_PKTOK_CNT_x)......................................................................................................... 253
13.4.2.12 Port x MAC Receive CRC Error Count Register (MAC_RX_CRCERR_CNT_x).......................................................................................... 254
13.4.2.13 Port x MAC Receive Multicast Count Register (MAC_RX_MULCST_CNT_x) ............................................................................................. 255
13.4.2.14 Port x MAC Receive Broadcast Count Register (MAC_RX_BRDCST_CNT_x) ........................................................................................... 256
13.4.2.15 Port x MAC Receive Pause Frame Count Register (MAC_RX_PAUSE_CNT_x) ........................................................................................ 257
13.4.2.16 Port x MAC Receive Fragment Error Count Register (MAC_RX_FRAG_CNT_x)........................................................................................ 258
13.4.2.17 Port x MAC Receive Jabber Error Count Register (MAC_RX_JABB_CNT_x) ............................................................................................. 259
13.4.2.18 Port x MAC Receive Alignment Error Count Register (MAC_RX_ALIGN_CNT_x) ...................................................................................... 260
13.4.2.19 Port x MAC Receive Packet Length Count Register (MAC_RX_PKTLEN_CNT_x) ..................................................................................... 261
13.4.2.20 Port x MAC Receive Good Packet Length Count Register (MAC_RX_GOODPKTLEN_CNT_x) ................................................................ 262
13.4.2.21 Port x MAC Receive Symbol Error Count Register (MAC_RX_SYMBOL_CNT_x) ...................................................................................... 263
13.4.2.22 Port x MAC Receive Control Frame Count Register (MAC_RX_CTLFRM_CNT_x) .................................................................................... 264
13.4.2.23 Port x MAC Transmit Configuration Register (MAC_TX_CFG_x) ................................................................................................................ 265
13.4.2.24 Port x MAC Transmit Flow Control Settings Register (MAC_TX_FC_SETTINGS_x) .................................................................................. 266
13.4.2.25 Port x MAC Transmit Deferred Count Register (MAC_TX_DEFER_CNT_x) ............................................................................................... 267
13.4.2.26 Port x MAC Transmit Pause Count Register (MAC_TX_PAUSE_CNT_x) ................................................................................................... 268
13.4.2.27 Port x MAC Transmit OK Count Register (MAC_TX_PKTOK_CNT_x) ........................................................................................................ 269
13.4.2.28 Port x MAC Transmit 64 Byte Count Register (MAC_TX_64_CNT_x) ......................................................................................................... 270
13.4.2.29 Port x MAC Transmit 65 to 127 Byte Count Register (MAC_TX_65_TO_127_CNT_x) ............................................................................... 271
13.4.2.30 Port x MAC Transmit 128 to 255 Byte Count Register (MAC_TX_128_TO_255_CNT_x) ........................................................................... 272
13.4.2.31 Port x MAC Transmit 256 to 511 Byte Count Register (MAC_TX_256_TO_511_CNT_x) ........................................................................... 273
13.4.2.32 Port x MAC Transmit 512 to 1023 Byte Count Register (MAC_TX_512_TO_1023_CNT_x) ....................................................................... 274
13.4.2.33 Port x MAC Transmit 1024 to Max Byte Count Register (MAC_TX_1024_TO_MAX_CNT_x)..................................................................... 275
13.4.2.34 Port x MAC Transmit Undersize Count Register (MAC_TX_UNDSZE_CNT_x) .......................................................................................... 276
13.4.2.35 Port x MAC Transmit Packet Length Count Register (MAC_TX_PKTLEN_CNT_x) .................................................................................... 277
13.4.2.36 Port x MAC Transmit Broadcast Count Register (MAC_TX_BRDCST_CNT_x) .......................................................................................... 278
13.4.2.37 Port x MAC Transmit Multicast Count Register (MAC_TX_MULCST_CNT_x) ............................................................................................ 279
13.4.2.38 Port x MAC Transmit Late Collision Count Register (MAC_TX_LATECOL_CNT_x) ................................................................................... 280
13.4.2.39 Port x MAC Transmit Excessive Collision Count Register (MAC_TX_EXCCOL_CNT_x)............................................................................ 281
13.4.2.40 Port x MAC Transmit Single Collision Count Register (MAC_TX_SNGLECOL_CNT_x) ............................................................................. 282
13.4.2.41 Port x MAC Transmit Multiple Collision Count Register (MAC_TX_MULTICOL_CNT_x) ............................................................................ 283
13.4.2.42 Port x MAC Transmit Total Collision Count Register (MAC_TX_TOTALCOL_CNT_x)................................................................................ 284
13.4.2.43 Port x MAC Interrupt Mask Register (MAC_IMR_x) ..................................................................................................................................... 285
13.4.2.44 Port x MAC Interrupt Pending Register (MAC_IPR_x) ................................................................................................................................. 286
13.4.3 Switch Engine CSRs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
13.4.3.1 Switch Engine ALR Command Register (SWE_ALR_CMD) ........................................................................................................................ 287
13.4.3.2 Switch Engine ALR Write Data 0 Register (SWE_ALR_WR_DAT_0) .......................................................................................................... 288
13.4.3.3 Switch Engine ALR Write Data 1 Register (SWE_ALR_WR_DAT_1) .......................................................................................................... 289
13.4.3.4 Switch Engine ALR Read Data 0 Register (SWE_ALR_RD_DAT_0)........................................................................................................... 291
13.4.3.5 Switch Engine ALR Read Data 1 Register (SWE_ALR_RD_DAT_1)........................................................................................................... 292
13.4.3.6 Switch Engine ALR Command Status Register (SWE_ALR_CMD_STS) .................................................................................................... 294
13.4.3.7 Switch Engine ALR Configuration Register (SWE_ALR_CFG) .................................................................................................................... 295
13.4.3.8 Switch Engine VLAN Command Register (SWE_VLAN_CMD).................................................................................................................... 296
13.4.3.9 Switch Engine VLAN Write Data Register (SWE_VLAN_WR_DATA).......................................................................................................... 297
13.4.3.10 Switch Engine VLAN Read Data Register (SWE_VLAN_RD_DATA) .......................................................................................................... 299
13.4.3.11 Switch Engine VLAN Command Status Register (SWE_VLAN_CMD_STS) ............................................................................................... 301
13.4.3.12 Switch Engine DIFFSERV Table Command Register (SWE_DIFFSERV_TBL_CFG)................................................................................. 302
13.4.3.13 Switch Engine DIFFSERV Table Write Data Register (SWE_DIFFSERV_TBL_WR_DATA) ...................................................................... 303
13.4.3.14 Switch Engine DIFFSERV Table Read Data Register (SWE_DIFFSERV_TBL_RD_DATA) ....................................................................... 304
13.4.3.15 Switch Engine DIFFSERV Table Command Status Register (SWE_DIFFSERV_TBL_CMD_STS) ............................................................ 305
13.4.3.16 Switch Engine Global Ingress Configuration Register (SWE_GLOBAL_INGRSS_CFG)............................................................................. 306
13.4.3.17 Switch Engine Port Ingress Configuration Register (SWE_PORT_INGRSS_CFG) ..................................................................................... 308
13.4.3.18 Switch Engine Admit Only VLAN Register (SWE_ADMT_ONLY_VLAN)..................................................................................................... 309
13.4.3.19 Switch Engine Port State Register (SWE_PORT_STATE)........................................................................................................................... 310
13.4.3.20 Switch Engine Priority to Queue Register (SWE_PRI_TO_QUE) ................................................................................................................ 311
13.4.3.21 Switch Engine Port Mirroring Register (SWE_PORT_MIRROR).................................................................................................................. 312
13.4.3.22 Switch Engine Ingress Port Type Register (SWE_INGRSS_PORT_TYP) ................................................................................................... 313
13.4.3.23 Switch Engine Broadcast Throttling Register (SWE_BCST_THROT) .......................................................................................................... 314
13.4.3.24 Switch Engine Admit Non Member Register (SWE_ADMT_N_MEMBER)................................................................................................... 315
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 9 Revision 1.5 (07-08-11)
DATASHEET
13.4.3.25 Switch Engine Ingress Rate Configuration Register (SWE_INGRSS_RATE_CFG) .................................................................................... 316
13.4.3.26 Switch Engine Ingress Rate Command Register (SWE_INGRSS_RATE_CMD)......................................................................................... 317
13.4.3.26.1Ingress Rate Table Registers.................................................................................................318
13.4.3.27 Switch Engine Ingress Rate Command Status Register (SWE_INGRSS_RATE_CMD_STS) .................................................................... 319
13.4.3.28 Switch Engine Ingress Rate Write Data Register (SWE_INGRSS_RATE_WR_DATA)............................................................................... 320
13.4.3.29 Switch Engine Ingress Rate Read Data Register (SWE_INGRSS_RATE_RD_DATA) ............................................................................... 321
13.4.3.30 Switch Engine Port 0 Ingress Filtered Count Register (SWE_FILTERED_CNT_0) ..................................................................................... 322
13.4.3.31 Switch Engine Port 1 Ingress Filtered Count Register (SWE_FILTERED_CNT_1) ..................................................................................... 323
13.4.3.32 Switch Engine Port 2 Ingress Filtered Count Register (SWE_FILTERED_CNT_2) ..................................................................................... 324
13.4.3.33 Switch Engine Port 0 Ingress VLAN Priority Regeneration Table Register (SWE_INGRSS_REGEN_TBL_0) ........................................... 325
13.4.3.34 Switch Engine Port 1 Ingress VLAN Priority Regeneration Table Register (SWE_INGRSS_REGEN_TBL_1) ........................................... 326
13.4.3.35 Switch Engine Port 2 Ingress VLAN Priority Regeneration Table Register (SWE_INGRSS_REGEN_TBL_2) ........................................... 327
13.4.3.36 Switch Engine Port 0 Learn Discard Count Register (SWE_LRN_DISCRD_CNT_0) .................................................................................. 328
13.4.3.37 Switch Engine Port 1 Learn Discard Count Register (SWE_LRN_DISCRD_CNT_1) .................................................................................. 329
13.4.3.38 Switch Engine Port 2 Learn Discard Count Register (SWE_LRN_DISCRD_CNT_2) .................................................................................. 330
13.4.3.39 Switch Engine Interrupt Mask Register (SWE_IMR)..................................................................................................................................... 331
13.4.3.40 Switch Engine Interrupt Pending Register (SWE_IPR)................................................................................................................................. 332
13.4.4 Buffer Manager CSRs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 334
13.4.4.1 Buffer Manager Configuration Register (BM_CFG)...................................................................................................................................... 334
13.4.4.2 Buffer Manager Drop Level Register (BM_DROP_LVL)............................................................................................................................... 335
13.4.4.3 Buffer Manager Flow Control Pause Level Register (BM_FC_PAUSE_LVL)............................................................................................... 336
13.4.4.4 Buffer Manager Flow Control Resume Level Register (BM_FC_RESUME_LVL) ........................................................................................ 337
13.4.4.5 Buffer Manager Broadcast Buffer Level Register (BM_BCST_LVL)............................................................................................................. 338
13.4.4.6 Buffer Manager Port 0 Drop Count Register (BM_DRP_CNT_SRC_0) ....................................................................................................... 339
13.4.4.7 Buffer Manager Port 1 Drop Count Register (BM_DRP_CNT_SRC_1) ....................................................................................................... 340
13.4.4.8 Buffer Manager Port 2 Drop Count Register (BM_DRP_CNT_SRC_2) ....................................................................................................... 341
13.4.4.9 Buffer Manager Reset Status Register (BM_RST_STS) .............................................................................................................................. 342
13.4.4.10 Buffer Manager Random Discard Table Command Register (BM_RNDM_DSCRD_TBL_CMD) ................................................................ 343
13.4.4.11 Buffer Manager Random Discard Table Write Data Register (BM_RNDM_DSCRD_TBL_WDATA) ........................................................... 344
13.4.4.12 Buffer Manager Random Discard Table Read Data Register (BM_RNDM_DSCRD_TBL_RDATA)............................................................ 345
13.4.4.13 Buffer Manager Egress Port Type Register (BM_EGRSS_PORT_TYPE) ................................................................................................... 346
13.4.4.14 Buffer Manager Port 0 Egress Rate Priority Queue 0/1 Register (BM_EGRSS_RATE_00_01) .................................................................. 348
13.4.4.15 Buffer Manager Port 0 Egress Rate Priority Queue 2/3 Register (BM_EGRSS_RATE_02_03) .................................................................. 349
13.4.4.16 Buffer Manager Port 1 Egress Rate Priority Queue 0/1 Register (BM_EGRSS_RATE_10_11) .................................................................. 350
13.4.4.17 Buffer Manager Port 1 Egress Rate Priority Queue 2/3 Register (BM_EGRSS_RATE_12_13) .................................................................. 351
13.4.4.18 Buffer Manager Port 2 Egress Rate Priority Queue 0/1 Register (BM_EGRSS_RATE_20_21) .................................................................. 352
13.4.4.19 Buffer Manager Port 2 Egress Rate Priority Queue 2/3 Register (BM_EGRSS_RATE_22_23) .................................................................. 353
13.4.4.20 Buffer Manager Port 0 Default VLAN ID and Priority Register (BM_VLAN_0) ............................................................................................. 354
13.4.4.21 Buffer Manager Port 1 Default VLAN ID and Priority Register (BM_VLAN_1) ............................................................................................. 355
13.4.4.22 Buffer Manager Port 2 Default VLAN ID and Priority Register (BM_VLAN_2) ............................................................................................. 356
13.4.4.23 Buffer Manager Port 0 Ingress Rate Drop Count Register (BM_RATE_DRP_CNT_SRC_0) ...................................................................... 357
13.4.4.24 Buffer Manager Port 1 Ingress Rate Drop Count Register (BM_RATE_DRP_CNT_SRC_1) ...................................................................... 358
13.4.4.25 Buffer Manager Port 2 Ingress Rate Drop Count Register (BM_RATE_DRP_CNT_SRC_2) ...................................................................... 359
13.4.4.26 Buffer Manager Interrupt Mask Register (BM_IMR) ..................................................................................................................................... 360
13.4.4.27 Buffer Manager Interrupt Pending Register (BM_IPR) ................................................................................................................................. 361
Chapter 14 Operational Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363
14.1 Absolute Maximum Ratings*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363
14.2 Operating Conditions** . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363
14.3 Power Consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
14.4 DC Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365
14.5 AC Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 367
14.5.1 Equivalent Test Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 367
14.5.2 Reset and Configuration Strap Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 368
14.5.3 Power-On Configuration Strap Valid Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
14.5.4 MII Interface Timing (MAC Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370
14.5.5 MII Interface Timing (PHY Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372
14.5.6 Turbo MII Interface Timing (MAC Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374
14.5.7 Turbo MII Interface Timing (PHY Mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 376
14.5.8 RMII Interface Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
14.5.9 SMI Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380
14.6 Clock Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 382
Chapter 15 Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383
15.1 72-QFN Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383
Chapter 16 Datasheet Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 10 SMSC LAN9303M/LAN9303Mi
DATASHEET
List of Figures
Figure 2.1 Internal Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 2.2 MII MAC Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Figure 2.3 MII/RMII PHY Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Figure 2.4 Port 0 MAC/PHY Management Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 3.1 Pin Assignments (TOP VIEW) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Figure 5.1 Functional Interrupt Register Hierarchy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Figure 6.1 Switch Fabric CSR Write Access Flow Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Figure 6.2 Switch Fabric CSR Read Access Flow Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Figure 6.3 ALR Table Entry Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Figure 6.4 Switch Engine Transmit Queue Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Figure 6.5 Switch Engine Transmit Queue Calculation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Figure 6.6 VLAN Table Entry Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Figure 6.7 Switch Engine Ingress Flow Priority Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Figure 6.8 Switch Engine Ingress Flow Priority Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Figure 6.9 Hybrid Port Tagging and Un-tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Figure 7.1 Port x PHY Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Figure 7.2 100BASE-TX Transmit Data Path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Figure 7.3 100BASE-TX Receive Data Path. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Figure 7.4 Direct Cable Connection vs. Cross-Over Cable Connection . . . . . . . . . . . . . . . . . . . . . . . . 107
Figure 8.1 I2C Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Figure 8.2 I2C EEPROM Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Figure 8.3 I2C EEPROM Byte Read . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Figure 8.4 I2C EEPROM Sequential Byte Reads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Figure 8.5 I2C EEPROM Byte Write . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Figure 8.6 EEPROM Access Flow Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Figure 8.7 EEPROM Loader Flow Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Figure 8.8 I2C Slave Addressing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Figure 8.9 I2C Slave Reads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Figure 8.10 I2C Slave Writes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Figure 10.1 MII Mux Management Path Connections - MAC Mode SMI Managed . . . . . . . . . . . . . . . . 139
Figure 10.2 MII Mux Management Path Connections - MAC Mode I2C Managed . . . . . . . . . . . . . . . . . 140
Figure 10.3 MII Mux Management Path Connections - PHY Mode SMI Managed . . . . . . . . . . . . . . . . . 141
Figure 10.4 MII Mux Management Path Connections - PHY Mode I2C Managed . . . . . . . . . . . . . . . . . 142
Figure 13.1 Base Register Memory Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
Figure 13.2 Example SWITCH_MAC_ADDRL, SWITCH_MAC_ADDRH, and EEPROM Setup . . . . . . 175
Figure 14.1 Output Equivalent Test Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 367
Figure 14.2 nRST Reset Pin Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 368
Figure 14.3 Power-On Configuration Strap Latching Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
Figure 14.4 MII Output Timing (MAC Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370
Figure 14.5 MII Input Timing (MAC Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371
Figure 14.6 MII Output Timing (PHY Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372
Figure 14.7 MII Input Timing (PHY Mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373
Figure 14.8 Turbo MII Output Timing (MAC Mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374
Figure 14.9 Turbo MII Input Timing (MAC Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 375
Figure 14.10Turbo MII Output Timing (PHY Mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 376
Figure 14.11Turbo MII Input Timing (PHY Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 377
Figure 14.12RMII Px_OUTCLK Output Mode Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
Figure 14.13RMII Px_OUTCLK Input Mode Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379
Figure 14.14SMI Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380
Figure 15.1 72-QFN Package Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383
Figure 15.2 72-QFN Recommended PCB Land Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 384
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 11 Revision 1.5 (07-08-11)
DATASHEET
List of Tables
Table 2.1 Device Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Table 3.1 LAN Port 1 Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table 3.2 LAN Port 2 Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table 3.3 LAN Port 1 & 2 Power and Common Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 3.4 Port 1 MII/RMII Pins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Table 3.5 Port 0 MII/RMII Pins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Table 3.6 GPIO/LED/Configuration Straps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Table 3.7 Serial Management/EEPROM Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Table 3.8 Miscellaneous Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Table 3.9 PLL Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Table 3.10 Core and I/O Power and Ground Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Table 3.11 LAN9303M/LAN9303Mi 72-QFN Package Pin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . 46
Table 3.12 Buffer Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Table 4.1 Reset Sources and Affected Device Circuitry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Table 4.2 Soft-Strap Configuration Strap Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Table 4.3 Hard-Strap Configuration Strap Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Table 4.4 PIN/Shared Strap Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Table 6.1 Switch Fabric Flow Control Enable Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Table 6.2 Spanning Tree States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Table 6.3 Typical Ingress Rate Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Table 6.4 Typical Broadcast Rate Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Table 6.5 Typical Egress Rate Settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Table 7.1 Default PHY Serial MII Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Table 7.2 4B/5B Code Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Table 7.3 PHY Interrupt Sources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Table 8.1 I2C EEPROM Size Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Table 8.2 EEPROM Contents Format Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Table 8.3 EEPROM Configuration Bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Table 10.1 SMI Frame Format. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Table 10.2 MII Management Frame Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Table 12.1 LED Operation as a Function of LED_FUN[1:0] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Table 13.1 Register Bit Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Table 13.2 System Control and Status Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
Table 13.3 SWITCH_MAC_ADDRL, SWITCH_MAC_ADDRH, and EEPROM Byte Ordering . . . . . . . . 174
Table 13.4 Switch Fabric CSR to SWITCH_CSR_DIRECT_DATA Address Range Map . . . . . . . . . . . . 176
Table 13.5 Virtual PHY MII Serially Adressable Register Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
Table 13.6 Emulated Link Partner Pause Flow Control Ability Default Values . . . . . . . . . . . . . . . . . . . . 191
Table 13.7 Emulated Link Partner Default Advertised Ability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
Table 13.8 Port 1 & 2 PHY MII Serially Adressable Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Table 13.9 10BASE-T Full Duplex Advertisement Default Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Table 13.1010BASE-T Half Duplex Advertisement Bit Default Value . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Table 13.11MODE[2:0] Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
Table 13.12Auto-MDIX Enable and Auto-MDIX State Bit Functionality . . . . . . . . . . . . . . . . . . . . . . . . . 224
Table 13.13MDIX Strap Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224
Table 13.14Indirectly Accessible Switch Control and Status Registers . . . . . . . . . . . . . . . . . . . . . . . . . 228
Table 13.15Metering/Color Table Register Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
Table 14.1 Supply and Current (10BASE-T Full-Duplex) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
Table 14.2 Supply and Current (100BASE-TX Full-Duplex) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
Table 14.3 Supply and Current (Power Management) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
Table 14.4 I/O Buffer Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365
Table 14.5 100BASE-TX Transceiver Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 366
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 12 SMSC LAN9303M/LAN9303Mi
DATASHEET
Table 14.6 10BASE-T Transceiver Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 366
Table 14.7 nRST Reset Pin Timing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 368
Table 14.8 Power-On Configuration Strap Latching Timing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
Table 14.9 MII Output Timing Values (MAC Mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370
Table 14.10MII Input Timing Values (MAC Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371
Table 14.11MII Output Timing Values (PHY Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372
Table 14.12MII Input Timing Values (PHY Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373
Table 14.13Turbo MII Output Timing Values (MAC Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374
Table 14.14Turbo MII Input Timing Values (MAC Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 375
Table 14.15Turbo MII Output Timing Values (PHY Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 376
Table 14.16Turbo MII Input Timing Values (PHY Mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 377
Table 14.17RMII Px_OUTCLK Output Mode Timing Values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
Table 14.18RMII Px_OUTCLK Input Mode Timing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379
Table 14.19SMI Timing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380
Table 14.20Crystal Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 382
Table 15.1 72-QFN Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383
Table 16.1 Customer Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 13 Revision 1.5 (07-08-11)
DATASHEET
Chapter 1 Preface
1.1 General Terms
10BASE-T 10BASE-T (10Mbps Ethernet, IEEE 802.3)
100BASE-TX 100BASE-TX (100Mbps Fast Ethernet, IEEE 802.3u)
ADC Analog-to-Digital Converter
ALR Address Logic Resolution
BLW Baseline Wander
BM Buffer Manager - Part of the switch fabric
BPDU Bridge Protocol Data Unit - Messages which carry the Spanning Tree
Protocol information
Byte 8-bits
CSMA/CD Carrier Sense Multiple Access / Collision Detect
CSR Control and Status Registers
CTR Counter
DA Destination Address
DWORD 32-bits
EPC EEPROM Controller
FCS Frame Check Sequence - The extra checksum characters added to the end
of an Ethernet frame, used for error detection and correction.
FIFO First In First Out buffer
FSM Finite State Machine
GPIO General Purpose I/O
Host External system (Includes processor, application software, etc.)
IGMP Internet Group Management Protocol
Inbound Refers to data input to the device from the host
Level-Triggered Sticky Bit This type of status bit is set whenever the condition that it represents is
asserted. The bit remains set until the condition is no longer true, and the
status bit is cleared by writing a zero.
lsb Least Significant Bit
LSB Least Significant Byte
MDI Medium Dependant Interface
MDIX Media Independent Interface with Crossover
MII Media Independent Interface
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 14 SMSC LAN9303M/LAN9303Mi
DATASHEET
MIIM Media Independent Interface Management
MIL MAC Interface Layer
MLT-3 Multi-Level Transmission Encoding (3-Levels). A tri-level encoding method
where a change in the logic level represents a code bit “1” and the logic
output remaining at the same level represents a code bit “0”.
msb Most Significant Bit
MSB Most Significant Byte
NRZI Non Return to Zero Inverted. This encoding method inverts the signal for a
“1” and leaves the signal unchanged for a “0”
N/A Not Applicable
NC No Connect
OUI Organizationally Unique Identifier
Outbound Refers to data output from the device to the host
PISO Parallel In Serial Out
PLL Phase Locked Loop
PTP Precision Time Protocol
RESERVED Refers to a reserved bit field or address. Unless otherwise noted, reserved
bits must always be zero for write operations. Unless otherwise noted, values
are not guaranteed when reading reserved bits. Unless otherwise noted, do
not read or write to reserved addresses.
RTC Real-Time Clock
SA Source Address
SFD Start of Frame Delimiter - The 8-bit value indicating the end of the preamble
of an Ethernet frame.
SIPO Serial In Parallel Out
SMI Serial Management Interface
SQE Signal Quality Error (also known as “heartbeat”)
SSD Start of Stream Delimiter
UDP User Datagram Protocol - A connectionless protocol run on top of IP
networks
UUID Universally Unique IDentifier
WORD 16-bits
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 15 Revision 1.5 (07-08-11)
DATASHEET
Chapter 2 Introduction
2.1 General Description
The LAN9303M/LAN9303Mi is a full featured, 3 port 10/100 managed Ethernet switch designed for
embedded applications where performance, flexibility, ease of integration and system cost control are
required. The LAN9303M/LAN9303Mi combines all the functions of a 10/100 switch system, including
the Switch Fabric, packet buffers, Buffer Manager, Media Access Controllers (MACs), PHY
transceivers, and serial management. The LAN9303M/LAN9303Mi complies with the IEEE 802.3
(full/half-duplex 10BASE-T and 100BASE-TX) Ethernet protocol specification and 802.1D/802.1Q
network management protocol specifications, enabling compatibility with industry standard Ethernet
and Fast Ethernet applications.
At the core of the device is the high performance, high efficiency 3 port Ethernet Switch Fabric. The
Switch Fabric contains a 3 port VLAN layer 2 Switch Engine that supports untagged, VLAN tagged,
and priority tagged frames. The Switch Fabric provides an extensive feature set which includes
spanning tree protocol support, multicast packet filtering and Quality of Service (QoS) packet
prioritization by VLAN tag, destination address, port default value or DIFFSERV/TOS, allowing for a
range of prioritization implementations. 32K of buffer RAM allows for the storage of multiple packets
while forwarding operations are completed, and a 512 entry forwarding table provides ample room for
MAC address forwarding tables. Each port is allocated a cluster of 4 dynamic QoS queues which allow
each queue size to grow and shrink with traffic, effectively utilizing all available memory. This memory
is managed dynamically via the Buffer Manager block within the Switch Fabric. All aspects of the
Switch Fabric are managed via the Switch Fabric configuration and status registers, which are
indirectly accessible via the system control and status registers.
The LAN9303M/LAN9303Mi provides 3 switched ports. Each port is fully compliant with the IEEE 802.3
standard and all internal MACs and PHYs support full/half duplex 10BASE-T and 100BASE-TX
operation. The LAN9303M/LAN9303Mi provides 2 on-chip PHYs, 1 Virtual PHY and 3 MACs. The
Virtual PHY and the third MAC are used to connect the Switch Fabric to an external MAC or PHY. In
MAC mode, the device can be connected to an external PHY via the MII/Turbo MII interface. In PHY
mode, the device can be connected to an external MAC via the MII/RMII/Turbo MII interface.
Optionally, the internal PHY on Port 1 can be disabled and the associated Switch Fabric port operated
in the MII/Turbo MII PHY, RMII PHY, or MII/Turbo MII MAC modes. All ports support automatic or
manual full duplex flow control or half duplex backpressure (forced collision) flow control. 2K jumbo
packet (2048 byte) support allows for oversized packet transfers, effectively increasing throughput
while decreasing CPU load. All MAC and PHY related settings are fully configurable via their respective
registers within the device.
The integrated I2C and SMI slave controllers allow for full serial management of the device via the
integrated I2C or MII interface, respectively. The inclusion of these interfaces allows for greater
flexibility in the incorporation of the device into various designs. It is this flexibility which allows the
device to operate in 2 different modes and under various management conditions. In both MAC and
PHY modes, the device can be SMI managed or I2C managed. This flexibility in management makes
the LAN9303M/LAN9303Mi a candidate for virtually all switch applications.
The LAN9303M/LAN9303Mi contains an I2C master EEPROM controller for connection to an optional
EEPROM. This allows for the storage and retrieval of static data. The internal EEPROM Loader can
be optionally configured to automatically load stored configuration settings from the EEPROM into the
device at reset. The I2C management slave and master EEPROM controller share common pins.
In addition to the primary functionality described above, the LAN9303M/LAN9303Mi provides additional
features designed for extended functionality. These include a configurable 16-bit General Purpose
Timer (GPT), a 32-bit 25MHz free running counter, and 6-bit configurable GPIO/LED interface.
The LAN9303M/LAN9303Mi’s performance, features and small size make it an ideal solution for many
applications in the consumer electronics and industrial automation markets. Targeted applications
include: set top boxes (cable, satellite and IP), digital televisions, digital video recorders, voice over IP
and video phone systems, home gateways, and test and measurement equipment.
SMSC LAN9303M/LAN9303Mi 16 Revision 1.5 (07-08-11)
DATASHEET
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
2.2 Block Diagram
Figure 2.1 Internal Block Diagram
To optional EEPROM
(via I2C master)
EEPROM Controller
I2C (master)
EEPROM Loader
Register
Access
MUX
SMI (slave)
Controller
System
Registers
(CSRs)
MII
Mode
MUX
MDIO
MDIO
To optional SMI Master
Mode Configuration
Straps
MDIO
PHY Management
Interface (PMI)
MDIO
Registers
Virtual PHY
10/100
PHY
Registers
10/100
PHY
Registers
Switch
Registers
(CSRs)
Switch Fabric
Dynamic
QoS
4 Queues
Dynamic
QoS
4 Queues
Dynamic
QoS
4 Queues
Switch Engine
Buffer Manager
Search
Engine
Frame
Buffers
MII
MDIO
Mode Configuration
Straps
MDIO
Ethernet
Ethernet
LAN9303M/
LAN9303Mi
GPIO/LED
Controller
To optional GPIOs/LEDs
System
Interrupt
Controller
IRQ
GP Timer
Free-Run
Clk
System
Clocks/
Reset/PME
Controller
External
25MHz Crystal
I2C
Port 0
10/100
MAC
Port 1
10/100
MAC
Port 2
10/100
MAC
MII
Mux/
Data
Path
MII
MII
I2C Slave
Controller
Mode Configuration
Straps
MII
Data
Path
To optional CPU
serial management
(via I2C slave)
MII/Turbo MII to PHY or
MII/RMII/Turbo MII to MAC
MII/Turbo MII to
PHY or MII/RMII/
Turbo MII to MAC
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 17 Revision 1.5 (07-08-11)
DATASHEET
2.2.1 System Clocks/Reset/PME Controller
A clock module generates all the system clocks required by the device. This module interfaces directly
with the external 25MHz crystal/oscillator to generate the required clock divisions for each internal
module. A 16-bit general purpose timer and 32-bit free-running clock are provided by this module for
general purpose use. The Port 1 & 2 PHYs provide general power-down and energy detect power-
down modes, which allow a reduction in PHY power consumption.
The device reset events are categorized as chip-level resets, multi-module resets, and single-module
resets. These reset events are summarized below:
Chip Level Resets
—Power-On Reset (Entire chip reset)
—nRST Pin Reset (Entire chip reset)
Multi-Module Reset
—Digital Reset (All sub-modules except Ethernet PHYs)
Single-Module Resets
—Port 2 PHY Reset
—Port 1 PHY Reset
—Virtual PHY Reset
2.2.2 System Interrupt Controller
The device provides a multi-tier programmable interrupt structure which is controlled by the System
Interrupt Controller. Top level interrupt registers aggregate and control all interrupts from the various
sub-modules. The device is capable of generating interrupt events from the following:
Switch Fabric
Ethernet PHYs
GPIOs
General Purpose Timer
Software (general purpose)
A dedicated programmable IRQ interrupt output pin is provided for external indication of any device
interrupts. The IRQ buffer type, polarity, and de-assertion interval are register configurable.
2.2.3 Switch Fabric
The Switch Fabric consists of the following major function blocks:
10/100 MACs
There is one 10/100 Ethernet MAC per Switch Fabric port, which provides basic 10/100 Ethernet
functionality, including transmission deferral, collision back-off/retry, TX/RX FCS
checking/generation, TX/RX pause flow control, and transmit back pressure. The 10/100 MACs act
as an interface between the Switch Engine and the 10/100 PHYs (for ports 1 and 2) or optional
external PHY/MAC on port 1. The port 0 10/100 MAC interfaces the Switch Engine to the external
MAC/PHY (see Section 2.3, "Modes of Operation"). Each 10/100 MAC includes RX and TX FIFOs
and per port statistic counters.
Switch Engine
This block, consisting of a 3 port VLAN layer 2 switching engine, provides the control for all
forwarding/filtering rules and supports untagged, VLAN tagged, and priority tagged frames. The
Switch Engine provides an extensive feature set which includes spanning tree protocol support,
multicast packet filtering and Quality of Service (QoS) packet prioritization by VLAN tag, destination
address, and port default value or DIFFSERV/TOS, allowing for a range of prioritization
implementations. A 512 entry forwarding table provides ample room for MAC address forwarding
tables.
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Buffer Manager
This block controls the free buffer space, multi-level transmit queues, transmission scheduling, and
packet dropping of the Switch Fabric. 32K of buffer RAM allows for the storage of multiple packets
while forwarding operations are completed. Each port is allocated a cluster of 4 dynamic QoS
queues which allow each queue size to grow and shrink with traffic, effectively utilizing all available
memory. This memory is managed dynamically via the Buffer Manager block.
Switch CSRs
This block contains all switch related control and status registers, and allows all aspects of the
Switch Fabric to be managed. These registers are indirectly accessible via the system control and
status registers.
2.2.4 Ethernet PHYs
The device contains three PHYs: Port 1 PHY, Port 2 PHY and a Virtual PHY. The Port 1 & 2 PHYs
are identical in functionality and each connect their corresponding Ethernet signal pins to the Switch
Fabric MAC of their respective port. These PHYs interface with their respective MAC via an internal
MII interface. The Virtual PHY provides the virtual functionality of a PHY and allows connection of an
external MAC to port 0 of the Switch Fabric as if it was connected to a single port PHY. All PHYs
comply with the IEEE 802.3 Physical Layer for Twisted Pair Ethernet and can be configured for full/half
duplex 100 Mbps (100BASE-TX) or 10Mbps (10BASE-T) Ethernet operation. All PHY registers follow
the IEEE 802.3 (clause 22.2.4) specified MII management register set.
2.2.5 PHY Management Interface (PMI)
The PHY Management Interface (PMI) is used to serially access the internal PHYs as well as the
external PHY on the MII pins (in MAC mode only, see Section 2.3, "Modes of Operation"). The PMI
implements the IEEE 802.3 management protocol, providing read/write commands for PHY
configuration.
2.2.6 I2C Slave Controller
This module provides an I2C slave interface which can be used for CPU serial management of the
device. The I2C slave controller implements the low level I2C slave serial interface (start and stop
condition detection, data bit transmission/reception, and acknowledge generation/reception), handles
the slave command protocol, and performs system register reads and writes. The I2C slave controller
conforms to the NXP I2C-Bus Specification. A list of management modes and configurations settings
for these modes is discussed in Section 2.3, "Modes of Operation"
2.2.7 SMI Slave Controller
This module provides a SMI slave interface which can be used for CPU management of the device
via the MII pins, and allows CPU access to all system CSRs. SMI uses the same pins and protocol of
the IEEE MII management function, and differs only in that SMI provides access to all internal registers
by using a non-standard extended addressing map. The SMI protocol co-exists with the MII
management protocol by using the upper half of the PHY address space (16 through 31). A list of
management modes and configurations settings for these modes is discussed in Section 2.3, "Modes
of Operation"
2.2.8 EEPROM Controller/Loader
The EEPROM Controller is an I2C master module which interfaces an optional external EEPROM with
the system register bus and the EEPROM Loader. Multiple sizes of external EEPROMs are supported
along with various EEPROM commands, allowing for the efficient storage and retrieval of static data.
The I2C interface conforms to the NXP I2C-Bus Specification.
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The EEPROM Loader module interfaces to the EEPROM Controller, Ethernet PHYs, and the system
CSRs. The EEPROM Loader provides the automatic loading of configuration settings from the
EEPROM into the device at reset, allowing the device to operate unmanaged. The EEPROM Loader
runs upon a pin reset (nRST), power-on reset (POR), digital reset, or upon the issuance of a EEPROM
RELOAD command.
2.2.9 GPIO/LED Controller
Six configurable general-purpose input/output pins are provided which are controlled via this module.
These pins can be individually configured via the GPIO/LED CSRs to function as inputs, push-pull
outputs, or open drain outputs and each is capable of interrupt generation with configurable polarity.
The GPIO pins can be alternatively configured as LED outputs to drive Ethernet status LEDs for
external indication of various attributes of the switch ports.
2.3 Modes of Operation
The LAN9303M/LAN9303Mi is designed to integrate into various embedded environments. To
accomplish compatibility with a wide range of applications, the LAN9303M/LAN9303Mi ports can
operate in the following modes:
Port 0 - Independently configured for MII MAC, MII PHY, RMII PHY modes
Port 1 - Independently configured for internal PHY, MII MAC, MII PHY, RMII PHY modes
Port 2 - Internal PHY mode
The mode of the device is determined by the P0_MODE[2:0] (Port 0) and P1_MODE[2:0] (Port 1) pin
straps.
The device can also be placed into the following management modes:
SMI managed
I2C managed
The management mode is determined by the MNGT1_LED4P and MNGT0_LED3P pin straps. These
modes are detailed in the following sections. Figure 2.4 displays a typical system configuration for each
Port 0 mode and management type supported by the device. Refer to Chapter 9, "MII Data Interfaces,"
on page 129 for additional information on the usage of MII signals in each supported mode.
2.3.1 Internal PHY Mode
Internal PHY mode (Port 1 and Port 2) utilizes the internal PHY for the network connection. The Switch
Engine MAC’s MII port is connected internally to the internal PHY in this mode. Internal PHY mode
can operate at 10Mbps or 100Mbps.
When an EEPROM is connected, the EEPROM loader can be used to load the initial device
configuration from the external EEPROM via the I2C interface. Once operational, if managed, the CPU
can use the I2C interface to read or write the EEPROM.
2.3.2 MAC Mode
Both Port 0 and Port 1 can be configured independently into MAC mode. MAC mode utilizes an
external PHY, which is connected to the port’s MII pins, to provide an Ethernet network connection. In
this mode, the port acts as a MAC, providing a communication path between the Switch Fabric and
the external PHY. MAC mode can operate at 10, 100, or 200Mbps (Turbo mode). In MAC mode, the
device may be SMI managed or I2C managed as detailed in Section 2.3.4, "Management Modes".
When an EEPROM is connected, the EEPROM loader can be used to load the initial device
configuration from the external EEPROM via the I2C interface. Once operational, if managed, the CPU
can use the I2C interface to read or write the EEPROM.
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DATASHEET
2.3.3 PHY Mode
Both Port 0 and Port 1 can be configured independently into PHY mode. PHY mode utilizes an external
MAC to provide a network path for the CPU. PHY mode supports MII and RMII interfaces. The external
MII/RMII pins must be connected to an external MAC, providing a communication path to the Switch
Fabric. MII PHY mode can operate at 10, 100, or 200Mbps (Turbo mode). RMII PHY mode can operate
at 10 or 100Mbps. In PHY mode, the device may be SMI managed or I2C managed as detailed in
Section 2.3.4, "Management Modes".
When an EEPROM is connected, the EEPROM loader can be used to load the initial device
configuration from the external EEPROM via the I2C interface. Once operational, if managed, the CPU
can use the I2C interface to read or write the EEPROM.
2.3.4 Management Modes
Various modes of management are provided in both MAC and PHY modes of operation. Two separate
interfaces may be used for management: the I2C interface or the SMI/MIIM (Media Independent
Interface Management) slave interface.
The I2C interface runs as an I2C slave. The slave mode is used as a register access path for an
external CPU. The I2C slave and I2C master EEPROM interface are shared interfaces.
Figure 2.2 MII MAC Mode
Figure 2.3 MII/RMII PHY Mode
10/100
PHY
Ethernet
Magnetics
MII
MIIM/
SMI
EEPROM
(optional)
I2C EEPROM/
I2C slave
I2C
LAN9303M/
LAN9303Mi
MII
10/100
MAC
MII
EEPROM
(optional)
I2C
MIIM/
SMI
LAN9303M/
LAN9303Mi
MII
I2C EEPROM/
I2C slave
10/100
MAC
RMII
EEPROM
(optional)
I2C
MIIM/
SMI
LAN9303M/
LAN9303Mi
RMII
I2C EEPROM/
I2C slave
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DATASHEET
The SMI/MIIM interface runs as either an SMI/MIIM slave or MIIM master. The master mode is used
to access an external PHYs registers under CPU control (assuming the CPU is using I2C). The slave
mode is used for register access by the CPU or external MAC and provides access to either the
internal Port 1&2 PHY registers or to all non-PHY registers (using addresses 16-31 and a non-standard
extended address map). MIIM and SMI use the same pins and protocol and differ only in that SMI
provides access to all internal registers while MIIM provides access to only the Port 1&2 PHY registers.
A special mode provides access to the Virtual PHY, which mimics the register operation of a single
port standalone PHY. This is used for software compatibility in managed operation.
The selection of management modes is determined at startup via the P0_MODE[2:0], MNGT1_LED4P,
and MNGT0_LED3P straps as detailed in Table 2. 1 . System configuration diagrams for each mode are
provided in Figure 2.4.
Note: The management mode is dependant on the mode of Port 0 (MAC or PHY mode). The Port 1
mode (MAC, PHY, or internal) is configured independently from the management mode.
Table 2.1 Device Modes
MODE
I2C INTERFACE
(MASTER/SLAVE)
SMI/MIIM
INTERFACE
P0_MODE[2:0]
STRAP VALUE
MNGT1_LED4P,
MNGT0_LED3PST
RAP VALUE
MAC SMI I2C master used to load
initial configuration from
EEPROM and for CPU
R/W access to
EEPROM
SMI/MIIM slave,
used for CPU access
to internal PHYs and
non-PHY registers
000 01
MAC I2CI
2C master used to load
initial configuration from
EEPROM and for CPU
R/W access to
EEPROM
I2C slave used for
management
MIIM master,
used for CPU access
to external PHY
registers
000 10
PHY SMI I2C master used to load
initial configuration from
EEPROM and for CPU
R/W access to
EEPROM
SMI/MIIM slave,
used for CPU access
to internal PHYs,
Virtual PHY, and non-
PHY registers
001,
010,
011,
100,
101,
or 110
01
PHY I2CI
2C master used to load
initial configuration from
EEPROM and for CPU
R/W access to
EEPROM
I2C slave used for
management
Virtual MIIM slave,
used for external
MAC access to
Virtual PHY registers
001,
010,
011,
100,
101,
or 110
10
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Figure 2.4 Port 0 MAC/PHY Management Modes
LAN9303M/LAN9303Mi MAC Modes
Ethernet
Magnetics
Ethernet
Magnetics
10/100
PHY
Ethernet
Magnetics
MII
EEPROM
(optional)
LAN9303M/
LAN9303Mi
I2C EEPROM/
I2C slave
I2C
MIIM/
SMI
SMI Managed
I2C Managed
Microprocessor/
Microcontroller
SMI/MIIM
MIIM
Ethernet
Magnetics
Ethernet
Magnetics
10/100
PHY
Ethernet
Magnetics
MII I2C
MIIM/
SMI
Microprocessor/
Microcontroller
EEPROM
(optional)
I2C EEPROM/
I2C slave
I2C
LAN9303M/
LAN9303Mi
LAN9303M/LAN9303Mi PHY Modes
SMI Managed
I2C Managed
MII
MII
Ethernet
Magnetics
Ethernet
Magnetics
10/100
MAC
MII
EEPROM
(optional)
I2C
MIIM/
SMI
Microprocessor/
Microcontroller
SMI/MIIM
LAN9303M/
LAN9303Mi
RMII/
MII
I2C EEPROM/
I2C slave
Ethernet
Magnetics
Ethernet
Magnetics
10/100
MAC
MII
MIIM/
SMI
Microprocessor/
Microcontroller
EEPROM
(optional)
I2C
LAN9303M/
LAN9303Mi
I2C EEPROM/
I2C slave
RMII/
MII
I2C
Ethernet
MIIM MIIM
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Chapter 3 Pin Description and Configuration
3.1 Pin Diagram
3.1.1 72-QFN Pin Diagram
Figure 3.1 Pin Assignments (TOP VIEW)
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3.2 Pin Descriptions
This section contains the descriptions of the device pins. The pin descriptions have been broken into
functional groups as follows:
LAN Port 1 Pins
LAN Port 2 Pins
LAN Port 1 & 2 Power and Common Pins
Port 1 MII/RMII Pins
Port 0 MII/RMII Pins
GPIO/LED/Configuration Straps
Serial Management/EEPROM Pins
Miscellaneous Pins
PLL Pins
Core and I/O Power and Ground Pins
Note: A list of buffer type definitions is provided in Section 3.3, "Buffer Types," on page 47.
Note: Please refer to the LAN9303M/LAN9303Mi Reference Schematic and LANCheck Schematic
Checklist on the SMSC website for additional connection information.
Note 3.1 The pin names for the twisted pair pins apply to a normal connection. If HP Auto-MDIX is
enabled and a reverse connection is detected or manually selected, the RX and TX pins
will be swapped internally.
Table 3.1 LAN Port 1 Pins
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
1Port 1 Ethernet
TX Negative
TXN1 AIO Negative output of Port 1 Ethernet transmitter. See
Note 3.1.
1Port 1 Ethernet
TX Positive
TXP1 AIO Positive output of Port 1 Ethernet transmitter. See
Note 3.1.
1Port 1 Ethernet
RX Negative
RXN1 AIO Negative input of Port 1 Ethernet receiver. See
Note 3.1.
1Port 1 Ethernet
RX Positive
RXP1 AIO Positive input of Port 1 Ethernet receiver. See
Note 3.1.
Table 3.2 LAN Port 2 Pins
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
1Port 2 Ethernet
TX Negative
TXN2 AIO Negative output of Port 2 Ethernet transmitter. See
Note 3.2.
1Port 2 Ethernet
TX Positive
TXP2 AIO Positive output of Port 2 Ethernet transmitter. See
Note 3.2.
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Note 3.2 The pin names for the twisted pair pins apply to a normal connection. If HP Auto-MDIX is
enabled and a reverse connection is detected or manually selected, the RX and TX pins
will be swapped internally.
Note 3.3 Please refer to the LAN9303M/LAN9303Mi Reference Schematic and LANCheck
Schematic Checklist on the SMSC website for additional connection information.
1Port 2 Ethernet
RX Negative
RXN2 AIO Negative input of Port 2 Ethernet receiver. See
Note 3.2.
1Port 2 Ethernet
RX Positive
RXP2 AIO Positive input of Port 2 Ethernet receiver. See
Note 3.2.
Table 3.3 LAN Port 1 & 2 Power and Common Pins
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
1Bias Reference EXRES AI Used for internal bias circuits. Connect to an
external 12.4K ohm, 1% resistor to ground.
2
+3.3V Port 1
Analog Power
Supply
VDD33A1 P See Note 3.3.
2
+3.3V Port 2
Analog Power
Supply
VDD33A2 P See Note 3.3.
1
+3.3V Master
Bias Power
Supply
VDD33BIAS P See Note 3.3.
1
Port 2
Transmitter
+1.8V Power
Supply
VDD18TX2 P This pin is supplied from the internal PHY voltage
regulator. This pin must be tied to the VDD18TX1
pin for proper operation.
See Note 3.3.
1
Port 1
Transmitter
+1.8V Power
Supply
VDD18TX1 P This pin must be connected directly to the
VDD18TX2 pin for proper operation.
See Note 3.3.
Table 3.2 LAN Port 2 Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
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Table 3.4 Port 1 MII/RMII Pins
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
1Port 1 MII Input
Data 3 P1_IND3
IS
(PD)
MII MAC Mode: This pin is the receive data 3 bit
from the external PHY to the switch.
IS
(PD)
MII PHY Mode: This pin is the transmit data 3 bit
from the external MAC to the switch. The pull-down
and input buffer are disabled when the Isolate bit is
set in the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
-RMII PHY Mode: This pin is not used.
(PD) Internal PHY Mode: This pin is not used.
1Port 1 MII Input
Data 2 P1_IND2
IS
(PD)
MII MAC Mode: This pin is the receive data 2 bit
from the external PHY to the switch.
IS
(PD)
MII PHY Mode: This pin is the transmit data 2 bit
from the external MAC to the switch. The pull-down
and input buffer are disabled when the Isolate bit is
set in the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
-RMII PHY Mode: This pin is not used.
(PD) Internal PHY Mode: This pin is not used.
1Port 1 MII Input
Data 1 P1_IND1
IS
(PD)
MII MAC Mode: This pin is the receive data 1 bit
from the external PHY to the switch.
IS
(PD)
MII PHY Mode: This pin is the transmit data 1 bit
from the external MAC to the switch. The pull-down
and input buffer are disabled when the Isolate bit is
set in the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
IS
(PD)
RMII PHY Mode: This pin is the transmit data 1 bit
from the external MAC to the switch. The pull-down
and input buffer are disabled when the Isolate bit is
set in the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
(PD) Internal PHY Mode: This pin is not used.
1Port 1 MII Input
Data 0 P1_IND0
IS
(PD)
MII MAC Mode: This pin is the receive data 0 bit
from the external PHY to the switch.
IS
(PD)
MII PHY Mode: This pin is the transmit data 0 bit
from the external MAC to the switch. The pull-down
and input buffer are disabled when the Isolate bit is
set in the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
IS
(PD)
RMII PHY Mode: This pin is the transmit data 0 bit
from the external MAC to the switch. The pull-down
and input buffer are disabled when the Isolate bit is
set in the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
(PD) Internal PHY Mode: This pin is not used.
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1Port 1 MII Input
Data Valid P1_INDV
IS
(PD)
MII MAC Mode: This pin is the RX_DV signal from
the external PHY and indicates valid data on
P1_IND[3:0] and P1_INER.
IS
(PD)
MII PHY Mode: This pin is the TX_EN signal from
the external MAC and indicates valid data on
P1_IND[3:0] and P1_INER. The pull-down and
input buffer are disabled when the Isolate bit is set
in the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
IS
(PD)
RMII PHY Mode: This pin is the TX_EN signal from
the external MAC and indicates valid data on
P1_IND[1:0]. The pull-down and input buffer are
disabled when the Isolate bit is set in the Port 1 MII
Basic Control Register
(P1_MII_BASIC_CONTROL).
(PD) Internal PHY Mode: This pin is not used.
1Port 1 MII Input
Error P1_INER
IS
(PD)
MII MAC Mode: This pin is the RX_ER signal from
the external PHY and indicates a receive error in
the packet.
IS
(PD)
MII PHY Mode: This pin is the TX_ER signal from
the external MAC and indicates that the current
packet should be aborted. The pull-down and input
buffer are disabled when the Isolate bit is set in the
Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
-RMII PHY Mode: This pin is not used.
(PD) Internal PHY Mode: This pin is not used.
1
Port 1 MII Input
Reference
Clock
P1_INCLK
IS
(PD)
MII MAC Mode: This pin is an input and is used as
the reference clock for the P1_IND[3:0], P1_INER,
and P1_INDV pins. It is connected to the receive
clock of the external PHY.
O12/O16 MII PHY Mode: This pin is an output and is used
as the reference clock for the P1_IND[3:0],
P1_INER, and P1_INDV pins. It is connected to the
transmit clock of the external MAC. The output
driver is disabled when the Isolate bit is set in the
Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL). When operating at
200MBps, the choice of drive strength is based on
the setting of the RMII/Turbo MII Clock Strength bit
in the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL). A low selects a 12
mA drive, while a high selects a 16 mA drive. A
series terminating resistor is recommended for the
best PCB signal integrity.
-RMII PHY Mode: This pin is not used.
(PD) Internal PHY Mode: This pin is not used.
Table 3.4 Port 1 MII/RMII Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
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1
Port 1 MII
Output Data 3 P1_OUTD3
O8 MII MAC Mode: This pin is the transmit data 3 bit
from the switch to the external PHY.
O8 MII PHY Mode: This pin is the receive data 3 bit
from the switch to the external MAC. The output
driver is disabled when the Isolate bit is set in the
Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
-RMII PHY Mode: This pin is not used.
-Internal PHY Mode: This pin is not used.
Port 1 Duplex
Polarity
Configuration
Strap
DUPLEX_POL_1 IS
(PU)
Note 3.5
This strap selects the default of the duplex polarity
strap for Port 1 MII (duplex_pol_strap_1) and is
used only in MII PHY, RMII PHY, and MII MAC
modes. See Note 3.4.
If the strap is value is 0, a 0 on P1_DUPLEX
means full duplex while a 1 means half duplex. If
the strap value is 1, a 1 on P1_DUPLEX means full
duplex, while a 0 means half duplex.
1
Port 1 MII
Output Data 2 P1_OUTD2
O8 MII MAC Mode: This pin is the transmit data 2 bit
from the switch to the external PHY.
O8 MII PHY Mode: This pin is the receive data 2 bit
from the switch to the external MAC. The output
driver is disabled when the Isolate bit is set in the
Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
-RMII PHY Mode: This pin is not used.
-Internal PHY Mode: This pin is not used.
Port 1 Mode[2]
Configuration
Strap
P1_MODE2 IS
(PU)
Note 3.5
This strap configures the mode for the Port 1 MII
pins. See Note 3.4.
Please refer to the P1_MODE0 strap entry for
mode encoding details.
1
Port 1 MII
Output Data 1 P1_OUTD1
O8 MII MAC Mode: This pin is the transmit data 1 bit
from the switch to the external PHY.
O8 MII PHY Mode: This pin is the receive data 1 bit
from the switch to the external MAC. The output
driver is disabled when the Isolate bit is set in the
Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
O8 RMII PHY Mode: This pin is the receive data 1 bit
from the switch to the external MAC. The output
driver is disabled when the Isolate bit is set in the
Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
-Internal PHY Mode: This pin is not used.
Port 1 Mode[1]
Configuration
Strap
P1_MODE1 IS
(PU)
Note 3.5
This strap configures the mode for the Port 1 MII
pins. See Note 3.4.
Please refer to the P1_MODE0 strap entry for
mode encoding details.
Table 3.4 Port 1 MII/RMII Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 29 Revision 1.5 (07-08-11)
DATASHEET
1
Port 1 MII
Output Data 0 P1_OUTD0
O8 MII MAC Mode: This pin is the transmit data 0 bit
from the switch to the external PHY.
O8 MII PHY Mode: This pin is the receive data 0 bit
from the switch to the external MAC. The output
driver is disabled when the Isolate bit is set in the
Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
O8 RMII PHY Mode: This pin is the receive data 0 bit
from the switch to the external MAC. The output
driver is disabled when the Isolate bit is set in the
Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL).
-Internal PHY Mode: This pin is not used.
Port 1 Mode[0]
Configuration
Strap
P1_MODE0 IS
(PU)
Note 3.5
This strap configures the mode for the Port 1 MII
pins. See Note 3.4.
The P1_MODE[2:0] configuration strap encoding is
as follows:
000 = MII MAC mode
001 = MII PHY mode
010 = MII PHY mode 200 Mbps 12 ma clock output
011 = MII PHY mode 200 Mbps 16 ma clock output
100 = RMII PHY mode clock is 12 ma output
101 = RMII PHY mode clock is 16 ma output
110 = RMII PHY mode clock is input
111 = Internal PHY mode
1
Port 1 MII
Output Data
Valid
P1_OUTDV
O8 MII MAC Mode: This pin is the TX_EN signal to the
external PHY and indicates valid data on
P1_OUTD[3:0].
O8 MII PHY Mode: This pin is the RX_DV signal to the
external MAC. The output driver is disabled when
the Isolate bit is set in the Port 1 MII Basic Control
Register (P1_MII_BASIC_CONTROL).
O8 RMII PHY Mode: This pin is the CRS_DV signal to
the external MAC. The output driver is disabled
when the Isolate bit is set in the Port 1 MII Basic
Control Register (P1_MII_BASIC_CONTROL).
-Internal PHY Mode: This pin is not used.
Table 3.4 Port 1 MII/RMII Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 30 SMSC LAN9303M/LAN9303Mi
DATASHEET
1
Port 1 MII
Output
Reference
Clock
P1_OUTCLK
IS
(PD)
MII MAC Mode: This pin is an input and is used as
the reference clock for the P1_OUTD[3:0] and
P1_OUTDV pins. It is connected to the transmit
clock of the external PHY.
O12/O16 MII PHY Mode: This pin is an output and is used
as the reference clock for the P1_OUT[3:0] and
P1_OUTDV pins. It is connected to the receive
clock of the external MAC. The output driver is
disabled when the Isolate bit is set in the Port 1 MII
Basic Control Register
(P1_MII_BASIC_CONTROL). When operating at
200MBps, the choice of drive strength is based on
the setting of the RMII/Turbo MII Clock Strength bit
in the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL). A low selects a 12
mA drive, while a high selects a 16 mA drive. A
series terminating resistor is recommended for the
best PCB signal integrity.
IS/O12/
O16
(PD)
RMII PHY Mode: This pin is an input or an output
running at 50 MHz and is used as the reference
clock for the P1_IND[1:0], P1_INDV,
P1_OUTD[1:0], and P1_OUTDV pins. The choice
of input verses output is based on the setting of the
RMII Clock Direction bit in the Port 1 MII Basic
Control Register (P1_MII_BASIC_CONTROL). A
low selects P1_OUTCLK as an input and a high
selects P1_OUTCLK as an output.
As an input, the pull-down is normally enabled. The
input buffer and pull-down are disabled when the
Isolate bit is set in the Port 1 MII Basic Control
Register (P1_MII_BASIC_CONTROL).
As an output, the input buffer and pull-down are
disabled. The choice of drive strength is based on
the setting of the RMII/Turbo MII Clock Strength bit
in the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL). A low selects a 12
mA drive, while a high selects a 16 mA drive. The
output driver is disabled when the Isolate bit is set
in the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL). A series terminating
resistor is recommended for the best PCB signal
integrity.
(PD) Internal PHY Mode: This pin is not used.
1Port 1 MII
Collision P1_COL
IS
(PU)
MII MAC Mode: This pin is an input from the
external PHY and indicates a collision event.
O8 MII PHY Mode: This pin is an output to the external
MAC indicating a collision event. The output driver
is disabled when the Isolate bit is set in the Port 1
MII Basic Control Register
(P1_MII_BASIC_CONTROL).
-RMII PHY Mode: This pin is not used.
(PU) Internal PHY Mode: This pin is not used.
Table 3.4 Port 1 MII/RMII Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 31 Revision 1.5 (07-08-11)
DATASHEET
Note 3.4 Configuration strap pins are identified by an underlined symbol name. Configuration strap
values are latched on power-on reset or nRST de-assertion. Each port has configuration
straps that control its operation. Additional strap pins, which share functionality with the
GPIO/LED pins, are described in Table 3.6. Some configuration straps can be overridden
by values from the EEPROM Loader. Please refer to Section 4.2.4, "Configuration Straps,"
on page 52 for further information.
Note 3.5 An external supplemental pull-up may be needed, depending upon the input current
loading of the external MAC/PHY device.
1Port 1 MII
Carrier Sense P1_CRS
IS
(PD)
MII MAC Mode: This pin is an input from the
external PHY indicating a network carrier.
O8 MII PHY Mode: This pin is an output to the external
MAC indicating a network carrier. The output driver
is disabled when the Isolate bit is set in the Port 1
MII Basic Control Register
(P1_MII_BASIC_CONTROL).
-RMII PHY Mode: This pin is not used.
(PD) Internal PHY Mode: This pin is not used.
1Port 1 MII
Duplex P1_DUPLEX
IS
(PU)
MII MAC Mode: This pin can be changed at any
time (live value) and can be overridden by enabling
the Manual Duplex bit in the Port 1 MII Basic
Control Register (P1_MII_BASIC_CONTROL). It is
typically tied to the duplex indication from the
external PHY. Please refer to the definition of the
DUPLEX_POL_1 strap for further details.
IS
(PU)
MII PHY and RMII PHY Modes: This pin sets the
default of the Duplex Mode bit in the Port 1 MII
Basic Control Register
(P1_MII_BASIC_CONTROL) and is typically tied
high or low as needed. The pull-up is enabled.
Please refer to the definition of the
DUPLEX_POL_1 strap for further details.
(PU) Internal PHY Mode: This pin is not used.
Table 3.5 Port 0 MII/RMII Pins
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
1Port 0 MII Input
Data 3 P0_IND3
IS
(PD)
MII MAC Mode: This pin is the receive data 3 bit
from the external PHY to the switch.
IS
(PD)
MII PHY Mode: This pin is the transmit data 3 bit
from the external MAC to the switch. The pull-down
and input buffer are disabled when the Isolate
(VPHY_ISO) bit is set in the Virtual PHY Basic
Control Register (VPHY_BASIC_CTRL).
-RMII PHY Mode: This pin is not used.
Table 3.4 Port 1 MII/RMII Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 32 SMSC LAN9303M/LAN9303Mi
DATASHEET
1Port 0 MII Input
Data 2 P0_IND2
IS
(PD)
MII MAC Mode: This pin is the receive data 2 bit
from the external PHY to the switch.
IS
(PD)
MII PHY Mode: This pin is transmit data 2 bit from
the external MAC to the switch. The pull-down and
input buffer are disabled when the Isolate
(VPHY_ISO) bit is set in the Virtual PHY Basic
Control Register (VPHY_BASIC_CTRL).
-RMII PHY Mode: This pin is not used.
1Port 0 MII Input
Data 1 P0_IND1
IS
(PD)
MII MAC Mode: This pin is the receive data 1 bit
from the external PHY to the switch.
IS
(PD)
MII PHY Mode: This pin is the transmit data 1 bit
from the external MAC to the switch. The pull-down
and input buffer are disabled when the Isolate
(VPHY_ISO) bit is set in the Virtual PHY Basic
Control Register (VPHY_BASIC_CTRL).
IS
(PD)
RMII PHY Mode: This pin is the transmit data 1 bit
from the external MAC to the switch. The pull-down
and input buffer are disabled when the Isolate
(VPHY_ISO) bit is set in the Virtual PHY Basic
Control Register (VPHY_BASIC_CTRL).
1Port 0 MII Input
Data 0 P0_IND0
IS
(PD)
MII MAC Mode: This pin is the receive data 0 bit
from the external PHY to the switch.
IS
(PD)
MII PHY Mode: This pin is the transmit data 0 bit
from the external MAC to the switch. The pull-down
and input buffer are disabled when the Isolate
(VPHY_ISO) bit is set in the Virtual PHY Basic
Control Register (VPHY_BASIC_CTRL).
IS
(PD)
RMII PHY Mode: This pin is the transmit data 0 bit
from the external MAC to the switch. The pull-down
and input buffer are disabled when the Isolate
(VPHY_ISO) bit is set in the Virtual PHY Basic
Control Register (VPHY_BASIC_CTRL).
1Port 0 MII Input
Data Valid P0_INDV
IS
(PD)
MII MAC Mode: This pin is the RX_DV signal from
the external PHY and indicates valid data on
P0_IND[3:0] and P0_INER.
IS
(PD)
MII PHY Mode: This pin is the TX_EN signal from
the external MAC and indicates valid data on
P0_IND[3:0] and P0_INER. The pull-down and
input buffer are disabled when the Isolate
(VPHY_ISO) bit is set in the Virtual PHY Basic
Control Register (VPHY_BASIC_CTRL).
IS
(PD)
RMII PHY Mode: This pin is the TX_EN signal from
the external MAC and indicates valid data on
P0_IND[1:0]. The pull-down and input buffer are
disabled when the Isolate (VPHY_ISO) bit is set in
the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL).
Table 3.5 Port 0 MII/RMII Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 33 Revision 1.5 (07-08-11)
DATASHEET
1Port 0 MII Input
Error P0_INER
IS
(PD)
MII MAC Mode: This pin is the RX_ER signal from
the external PHY and indicates a receive error in
the packet.
IS
(PD)
MII PHY Mode: This pin is the TX_ER signal from
the external MAC and indicates that the current
packet should be aborted. The pull-down and input
buffer are disabled when the Isolate (VPHY_ISO)
bit is set in the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL).
-RMII PHY Mode: This pin is not used.
1
Port 0 MII Input
Reference
Clock
P0_INCLK
IS
(PD)
MII MAC Mode: This pin is an input and is used as
the reference clock for the P0_IND[3:0], P0_INER,
and P0_INDV pins. It is connected to the receive
clock of the external PHY.
O12/O16 MII PHY Mode: This pin is an output and is used
as the reference clock for the P0_IND[3:0],
P0_INER, and P0_INDV pins. It is connected to the
transmit clock of the external MAC. The output
driver is disabled when the Isolate (VPHY_ISO) bit
is set in the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL). When operating at
200MBps, the choice of drive strength is based on
the setting of the RMII/Turbo MII Clock Strength bit
in the Virtual PHY Special Control/Status Register
(VPHY_SPECIAL_CONTROL_STATUS). A low
selects a 12 mA drive, while a high selects a 16 mA
drive. A series terminating resistor is recommended
for the best PCB signal integrity.
-RMII PHY Mode: This pin is not used.
1
Port 0 MII
Output Data 3 P0_OUTD3
O8 MII MAC Mode: This pin is the transmit data 3 bit
from the switch to the external PHY.
O8 MII PHY Mode: This pin is the receive data 3 bit
from the switch to the external MAC. The output
driver is disabled when the Isolate (VPHY_ISO) bit
is set in the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL).
-RMII PHY Mode: This pin is not used
Port 0 Duplex
Polarity
Configuration
Strap
DUPLEX_POL_0 IS
(PU)
Note 3.7
This strap selects the default of the duplex polarity
strap for Port 0 MII (duplex_pol_strap_0). See
Note 3.6.
If the strap is value is 0, a 0 on P0_DUPLEX
means full duplex while a 1 means half duplex. If
the strap value is 1, a 1 on P0_DUPLEX means full
duplex, while a 0 means half duplex.
Table 3.5 Port 0 MII/RMII Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 34 SMSC LAN9303M/LAN9303Mi
DATASHEET
1
Port 0 MII
Output Data 2 P0_OUTD2
O8 MII MAC Mode: This pin is the transmit data 2 bit
from the switch to the external PHY.
O8 MII PHY Mode: This pin is the receive data 2 bit
from the switch to the external MAC. The output
driver is disabled when the Isolate (VPHY_ISO) bit
is set in the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL).
-RMII PHY Mode: This pin is not used
Port 0 Mode[2]
Configuration
Strap
P0_MODE2 IS
(PU)
Note 3.7
This strap configures the mode for Port 0. See
Note 3.6.
Please refer to the P0_MODE0 strap entry for
mode encoding details.
1
Port 0 MII
Output Data 1 P0_OUTD1
O8 MII MAC Mode: This pin is the transmit data 1 bit
from the switch to the external PHY.
O8 MII PHY Mode: This pin is the receive data 1 bit
from the switch to the external MAC. The output
driver is disabled when the Isolate (VPHY_ISO) bit
is set in the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL).
O8 RMII PHY Mode: This pin is the receive data 1 bit
from the switch to the external MAC. The output
driver is disabled when the Isolate (VPHY_ISO) bit
is set in the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL).
Port 0 Mode[1]
Configuration
Strap
P0_MODE1 IS
(PU)
Note 3.7
This strap configures the mode for Port 0. See
Note 3.6.
Please refer to the P0_MODE0 strap entry for
mode encoding details.
Table 3.5 Port 0 MII/RMII Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 35 Revision 1.5 (07-08-11)
DATASHEET
1
Port 0 MII
Output Data 0 P0_OUTD0
O8 MII MAC Mode: This pin is the transmit data 0 bit
from the switch to the external PHY.
O8 MII PHY Mode: This pin is the receive data 0 bit
from the switch to the external MAC. The output
driver is disabled when the Isolate (VPHY_ISO) bit
is set in the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL).
O8 RMII PHY Mode: This pin is the receive data 0 bit
from the switch to the external MAC. The output
driver is disabled when the Isolate (VPHY_ISO) bit
is set in the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL).
Port 0 Mode[0]
Configuration
Strap
P0_MODE0 IS
(PU)
Note 3.7
This strap configures the mode for Port 0. See
Note 3.6.
The P0_MODE[2:0] configuration strap encoding is
as follows:
000 = MII MAC mode
001 = MII PHY mode
010 = MII PHY mode 200 Mbps 12 ma clock output
011 = MII PHY mode 200 Mbps 16 ma clock output
100 = RMII PHY mode clock is 12 ma output
101 = RMII PHY mode clock is 16 ma output
110 = RMII PHY mode clock is input
111 = RESERVED
1
Port 0 MII
Output Data
Valid
P0_OUTDV
O8 MII MAC Mode: This pin is the TX_EN signal to the
external PHY and indicates valid data on
P0_OUTD[3:0].
O8 MII PHY Mode: This pin is the RX_DV signal to the
external MAC. The output driver is disabled when
the Isolate (VPHY_ISO) bit is set in the Virtual PHY
Basic Control Register (VPHY_BASIC_CTRL).
O8 RMII PHY Mode: This pin is the CRS_DV signal to
the external MAC. The output driver is disabled
when the Isolate (VPHY_ISO) bit is set in the
Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL).
Table 3.5 Port 0 MII/RMII Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 36 SMSC LAN9303M/LAN9303Mi
DATASHEET
1
Port 0 MII
Output
Reference
Clock
P0_OUTCLK
IS
(PD)
MII MAC Mode: This pin is an input and is used as
the reference clock for the P0_OUTD[3:0] and
P0_OUTDV pins. It is connected to the transmit
clock of the external PHY.
O12/O16 MII PHY Mode: This pin is an output and is used
as the reference clock for the P0_OUT[3:0] and
P0_OUTDV pins. It is connected to the receive
clock of the external MAC. The output driver is
disabled when the Isolate (VPHY_ISO) bit is set in
the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL). When operating at
200MBps, the choice of drive strength is based on
the setting of the RMII/Turbo MII Clock Strength bit
in the Virtual PHY Special Control/Status Register
(VPHY_SPECIAL_CONTROL_STATUS). A low
selects a 12 mA drive, while a high selects a 16 mA
drive. A series terminating resistor is recommended
for the best PCB signal integrity.
IS/O12/
O16
(PD)
RMII PHY Mode: This pin is an input or an output
running at 50 MHz and is used as the reference
clock for the P0_IND[1:0], P0_INDV,
P0_OUTD[1:0], and P0_OUTDV pins. The choice
of input verses output is based on the setting of the
RMII Clock Direction bit in the Virtual PHY Special
Control/Status Register
(VPHY_SPECIAL_CONTROL_STATUS). A low
selects P0_OUTCLK as an input and a high selects
P0_OUTCLK as an output.
As an input, the pull-down is normally enabled. The
input buffer and pull-down are disabled when the
Isolate (VPHY_ISO) bit is set in the Virtual PHY
Basic Control Register (VPHY_BASIC_CTRL).
As an output, the input buffer and pull-down are
disabled. The choice of drive strength is based on
the MII Virtual PHY RMII/Turbo MII Clock Strength
bit. A low selects a 12 mA drive, while a high
selects a 16 mA drive. The output driver is disabled
when the Isolate (VPHY_ISO) bit is set in the
Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL). A series terminating
resistor is recommended for the best PCB signal
integrity.
1Port 0 MII
Collision P0_COL
IS
(PU)
MII MAC Mode: This pin is an input from the
external PHY and indicates a collision event.
O8 MII PHY Mode: This pin is an output to the external
MAC indicating a collision event. The output driver
is disabled when the Isolate (VPHY_ISO) bit is set
in the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL).
-RMII PHY Mode: This pin is not used.
Table 3.5 Port 0 MII/RMII Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 37 Revision 1.5 (07-08-11)
DATASHEET
Note 3.6 Configuration strap pins are identified by an underlined symbol name. Configuration strap
values are latched on power-on reset or nRST de-assertion. Each port has configuration
straps that control its operation. Additional strap pins, which share functionality with the
GPIO/LED pins, are described in Table 3.6. Some configuration straps can be overridden
by values from the EEPROM Loader. Please refer to Section 4.2.4, "Configuration Straps,"
on page 52 for further information.
1Port 0 MII
Carrier Sense P0_CRS
IS
(PD)
MII MAC Mode: This pin is an input from the
external PHY indicating a network carrier.
O8 MII PHY Mode: This pin is an output to the external
MAC indicating a network carrier. The output driver
is disabled when the Isolate (VPHY_ISO) bit is set
in the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL).
-RMII PHY Mode: This pin is not used.
1Port 0 MII
Duplex P0_DUPLEX
IS
(PU)
MII MAC Mode: This pin can be changed at any
time (live value) and can be overridden by enabling
the Auto-Negotiation (VPHY_AN) bit in the Virtual
PHY Basic Control Register
(VPHY_BASIC_CTRL). It is typically tied to the
duplex indication from the external PHY. Please
refer to the definition of the DUPLEX_POL_0 strap
for further details.
IS
(PU)
MII PHY and RMII PHY Modes: This pin is used
to determine the virtual link partner’s ability bits and
is typically tied high or low, as needed. Please refer
to the definition of the DUPLEX_POL_0 strap for
further details.
1
Management
Data
Input/Output
MDIO IS/O8
SMI/MII Slave Management Modes: This is the
data to/from an external master
MII Master Management Modes: This is the data
to/from an external PHY.
Note: An external pull-up is required when the
SMI or MII management interface is used,
to ensure that the IDLE state of the MDIO
signal is a logic one.
Note: An external pull-up is recommended when
the SMI or MII management interface is
not used, to avoid a floating signal.
1
MII
Management
Clock
MDC
IS SMI/MII Slave Management Modes: This is the
clock input from an external master.
Note: When SMI or MII is not used, an external
pull-down is recommended to avoid a
floating signal.
O8 MII Master Management Modes: This is the clock
output to an external PHY.
Table 3.5 Port 0 MII/RMII Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 38 SMSC LAN9303M/LAN9303Mi
DATASHEET
Note 3.7 An external supplemental pull-up may be needed, depending upon the input current
loading of the external MAC/PHY device.
Table 3.6 GPIO/LED/Configuration Straps
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
1
LED 5 LED5 O12/
OD12/
OS12
This pin is configured to operate as an LED when
the LED 5 Enable bit of the LED Configuration
Register (LED_CFG) is set. The buffer type
depends on the setting of the LED Function 1-0
(LED_FUN[1:0]) field in the LED Configuration
Register (LED_CFG) and is configured to be either
an push-pull or open-drain/open-source output.
When selected as an open-drain/open-source
output, the polarity of this pin depends upon the
PHYADDR_LED5P strap value sampled at reset.
GPIO 5 GPIO5 IS/O12/
OD12
(PU)
This pin is configured to operate as a GPIO when
the LED 5 Enable bit of the LED Configuration
Register (LED_CFG) is clear. The pin is fully
programmable as either a push-pull output, an
open-drain output, or a Schmitt-triggered input by
writing the General Purpose I/O Configuration
Register (GPIO_CFG) and the General Purpose
I/O Data & Direction Register (GPIO_DATA_DIR).
PHY Address
and LED 5
Polarity
Configuration
Strap
PHYADDR_LED5P IS
(PU)
This strap configures the default value of the MII
management address for the PHYs and Virtual
PHY, as well as the polarity of the LED 5 pin when
it is an open-drain or open-source output. See
Note 3.8.
If the strap value is 0:
The PHY address values are as follows:
Virtual PHY = 0
PHY Port 1 = 1
PHY Port 2 = 2
The LED is set as active high, since it is assumed
that a LED to ground is used as the pull-down.
If the strap value is 1:
The PHY address values are as follows:
Virtual PHY = 1
PHY Port 1 = 2
PHY Port 2 = 3
The LED is set as active low, since it is assumed
that a LED to VDD is used as the pull-up.
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 39 Revision 1.5 (07-08-11)
DATASHEET
1
LED 4 LED4 O12/
OD12/
OS12
This pin is configured to operate as an LED when
the LED 4 Enable bit in the LED Configuration
Register (LED_CFG) is set. The buffer type
depends on the setting of the LED Function 1-0
(LED_FUN[1:0]) field in the LED Configuration
Register (LED_CFG) and is configured to be either
an push-pull or open-drain/open-source output.
When selected as an open-drain/open-source
output, the polarity of this pin depends up the
MNGT1_LED4P strap value sampled at reset.
GPIO 4 GPIO4 IS/O12/
OD12
(PU)
This pin is configured to operate as a GPIO when
the LED 4 Enable bit of the LED Configuration
Register (LED_CFG) is clear. The pin is fully
programmable as either a push-pull output, an
open-drain output, or a Schmitt-triggered input by
writing the General Purpose I/O Configuration
Register (GPIO_CFG) and the General Purpose
I/O Data & Direction Register (GPIO_DATA_DIR).
Serial
Management
Mode[1] and
LED 4 Polarity
Configuration
Strap
MNGT1_LED4P IS
(PU)
This strap configures the Serial Management
Mode, as well as the polarity of the LED 4 pin when
it is an open-drain or open-source output. See
Note 3.8.
If the strap value is 0:
The LED is set as active high, since it is assumed
that a LED to ground is used as the pull-down.
If the strap value is 1:
The LED is set as active low, since it is assumed
that a LED to VDD is used as the pull-up.
Table 3.6 GPIO/LED/Configuration Straps (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
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1
LED 3 LED3 O12/
OD12/
OS12
This pin is configured to operate as an LED when
the LED 3 Enable bit in the LED Configuration
Register (LED_CFG) is set. The buffer type
depends on the setting of the LED Function 1-0
(LED_FUN[1:0]) field in the LED Configuration
Register (LED_CFG) and is configured to be either
an push-pull or open-drain/open-source output.
When selected as an open-drain/open-source
output, the polarity of this pin depends up the
MNGT0_LED3P strap value sampled at reset.
GPIO 3 GPIO3 IS/O12/
OD12
(PU)
This pin is configured to operate as a GPIO when
the LED 3 Enable bit of the LED Configuration
Register (LED_CFG) is clear. The pin is fully
programmable as either a push-pull output, an
open-drain output, or a Schmitt-triggered input by
writing the General Purpose I/O Configuration
Register (GPIO_CFG) and the General Purpose
I/O Data & Direction Register (GPIO_DATA_DIR).
Serial
Management
Mode[0] and
LED 3 Polarity
Configuration
Strap
MNGT0_LED3P IS
(PU)
This strap configures the Serial Management
Mode, as well as the polarity of the LED 3 pin when
it is an open-drain or open-source output. See
Note 3.8.
For LED3, If the strap value is 0:
The LED is set as active high, since it is assumed
that a LED to ground is used as the pull-down.
If the strap value is 1:
The LED is set as active low, since it is assumed
that a LED to VDD is used as the pull-up.
Table 3.6 GPIO/LED/Configuration Straps (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
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1
LED 2 LED2 O12/
OD12/
OS12
This pin is configured to operate as an LED when
the LED 2 Enable bit in the LED Configuration
Register (LED_CFG) is set. The buffer type
depends on the setting of the LED Function 1-0
(LED_FUN[1:0]) field in the LED Configuration
Register (LED_CFG) and is configured to be either
an push-pull or open-drain/open-source output.
When selected as an open-drain/open-source
output, the polarity of this pin depends up the
E2PSIZE_LED2P strap value sampled at reset.
GPIO 2 GPIO2 IS/O12/
OD12
(PU)
This pin is configured to operate as a GPIO when
the LED 2 Enable bit of the LED Configuration
Register (LED_CFG) is clear. The pin is fully
programmable as either a push-pull output, an
open-drain output, or a Schmitt-triggered input by
writing the General Purpose I/O Configuration
Register (GPIO_CFG) and the General Purpose
I/O Data & Direction Register (GPIO_DATA_DIR).
EEPROM Size
and
LED 2 Polarity
Configuration
Strap
E2PSIZE_LED2P IS
(PU)
This strap configures the EEPROM size, as well as
the polarity of the LED 2 pin when it is an open-
drain or open-source output. See Note 3.8.
The low bit of the EEPROM size range is set to the
strap value. When 0, EEPROM sizes 16 x 8
through 2048 x 8 are supported. When 1,
EEPROM sizes 4096 x 8 through 65536 x 8 are
supported.
For LED 2, If the strap value is 0:
The LED is set as active high, since it is assumed
that a LED to ground is used as the pull-down.
If the strap value is 1:
The LED is set as active low, since it is assumed
that a LED to VDD is used as the pull-up.
Table 3.6 GPIO/LED/Configuration Straps (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
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1
LED 1 LED1 O12/
OD12/
OS12
This pin is configured to operate as an LED when
the LED 1 Enable bit in the LED Configuration
Register (LED_CFG) is set. The buffer type
depends on the setting of the LED Function 1-0
(LED_FUN[1:0]) field in the LED Configuration
Register (LED_CFG) and is configured to be either
an push-pull or open-drain/open-source output.
When selected as an open-drain/open-source
output, the polarity of this pin depends up the
AMDIX2_LED1P strap value sampled at reset.
GPIO 1 GPIO1 IS/O12/
OD12
(PU)
This pin is configured to operate as a GPIO when
the LED 1 Enable bit of the LED Configuration
Register (LED_CFG) is clear. The pin is fully
programmable as either a push-pull output, an
open-drain output, or a Schmitt-triggered input by
writing the General Purpose I/O Configuration
Register (GPIO_CFG) and the General Purpose
I/O Data & Direction Register (GPIO_DATA_DIR).
Port 2 Auto-
MDIX Enable
and
LED 1 Polarity
Configuration
Strap
AMDIX2_LED1P IS
(PU)
This strap configures the default for the Auto-MDIX
soft-strap for LAN Port 2, as well as the polarity of
the LED 1 pin when it is an open-drain or open-
source output. See Note 3.8.
The strap value determines whether or not LAN
Port 2 Auto-MDIX is enables as follows:
0 = Disabled
1 = Enabled
For LED 1, If the strap value is 0:
The LED is set as active high, since it is assumed
that a LED to ground is used as the pull-down.
If the strap value is 1:
The LED is set as active low, since it is assumed
that a LED to VDD is used as the pull-up.
Table 3.6 GPIO/LED/Configuration Straps (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
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Note 3.8 Configuration strap pins are identified by an underlined symbol name. Configuration strap
values are latched on power-on reset or nRST de-assertion. In addition to the configuration
strap pins that control GPIO/LED and Auto-MDIX operation listed in Tabl e 3 . 6 ,
configuration strap pins are associated with each port and control their operation. They are
described in Ta b le 3 . 4 and Ta bl e 3 . 5 . Some configuration straps can be overridden by
values from the EEPROM Loader. Please refer to Section 4.2.4, "Configuration Straps," on
page 52 for further information.
1
LED 0 LED0 O12/
OD12/
OS12
This pin is configured to operate as an LED when
the LED 0 Enable bit in the LED Configuration
Register (LED_CFG) is set. The buffer type
depends on the setting of the field in the LED
Configuration Register (LED_CFG) and is
configured to be either an push-pull or open-
drain/open-source output. When selected as an
open-drain/open-source output, the polarity of this
pin depends up the AMDIX1_LED0P strap value
sampled at reset.
GPIO 0 GPIO0 IS/O12/
OD12
(PU)
This pin is configured to operate as a GPIO when
the LED 0 Enable bit of the LED Configuration
Register (LED_CFG) is clear. The pin is fully
programmable as either a push-pull output, an
open-drain output, or a Schmitt-triggered input by
writing the General Purpose I/O Configuration
Register (GPIO_CFG) and the General Purpose
I/O Data & Direction Register (GPIO_DATA_DIR).
Port 1 Auto-
MDIX Enable
and
LED 0 Polarity
Configuration
Strap
AMDIX1_LED0P IS
(PU)
This strap configures the default for the Auto-MDIX
soft-strap for LAN Port 1, as well as the polarity of
the LED 0 pin when it is an open-drain or open-
source output. See Note 3.8.
The strap value determines whether or not LAN
Port 1 Auto-MDIX is enabled as follows:
0 = Disabled
1 = Enabled
For LED 0, If the strap value is 0:
The LED is set as active high, since it is assumed
that a LED to ground is used as the pull-down.
If the strap value is 1:
The LED is set as active low, since it is assumed
that a LED to VDD is used as the pull-up.
Table 3.6 GPIO/LED/Configuration Straps (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
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Note: Please refer to Chapter 8, "Serial Management," on page 114 for additional information
regarding serial management configuration and functionality.
Table 3.7 Serial Management/EEPROM Pins
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
1
EEPROM I2C
Serial Data
Input/Output
EE_SDA IS/OD8 When the device is accessing an external
EEPROM, this pin is the I2C serial data
input/output.
Note: This pin must be pulled-up by an external
resistor at all times.
I2C Slave Serial
Data
Input/Output
(I2C Slave
Mode)
SDA IS/OD8 In I2C slave mode, this pin is the I2C serial data
input/output from/to the external master.
Note: This pin must be pulled-up by an external
resistor at all times.
1
EEPROM I2C
Serial Clock
EE_SCL IS/OD8 When the device is accessing an external
EEPROM, this pin is the I2C clock input/open-drain
output.
Note: This pin must be pulled-up by an external
resistor at all times.
I2C Slave Serial
Clock
(I2C Slave
Mode)
SCL IS In I2C slave mode, this pin is the I2C clock input
from the external master.
Note: This pin must be pulled-up by an external
resistor at all times.
Table 3.8 Miscellaneous Pins
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
1
Interrupt Output IRQ O8/OD8 The polarity, source and buffer type of this signal is
programmable via the Interrupt Configuration
Register (IRQ_CFG). Please refer to Chapter 5,
"System Interrupts," on page 62 for further details.
1
System Reset
Input
nRST IS
(PU)
This active low signal allows external hardware to
reset the device. The device also contains an
internal power-on reset circuit. Thus, this signal
may be left unconnected if an external hardware
reset is not needed. When used, this signal must
adhere to the reset timing requirements as detailed
in the Section 14.5.2, "Reset and Configuration
Strap Timing," on page 368.
1
Test 1 TEST1 AI This pin must be tied to VDD33IO for proper
operation.
1Test 2 TEST2 IS
(PD)
This pin must be tied to VSS for proper operation.
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Note 3.9 Please refer to the LAN9303M/LAN9303Mi Reference Schematic and LANCheck
Schematic Checklist on the SMSC website for additional connection information.
Note 3.10 Please refer to the LAN9303M/LAN9303Mi Reference Schematic and LANCheck
Schematic Checklist on the SMSC website for additional connection information.
Table 3.9 PLL Pins
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
1
PLL +1.8V
Power Supply
VDD18PLL P This pin must be connected to VDD18CORE for
proper operation.
See Note 3.9.
1
Crystal Input XI ICLK External 25MHz crystal input. This signal can also
be driven by a single-ended clock oscillator. When
this method is used, XO should be left
unconnected.
1 Crystal Output XO OCLK External 25MHz crystal output.
Table 3.10 Core and I/O Power and Ground Pins
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
5
+3.3V I/O
Power
VDD33IO P +3.3V Power Supply for I/O Pins and Internal
Regulator.
See Note 3.10.
2
Digital Core
+1.8V Power
Supply Output
VDD18CORE P +1.8V power from the internal core voltage
regulator. All VDD18CORE pins must be tied
together for proper operation.
See Note 3.10.
1
PAD
Common
Ground
VSS P Ground
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Table 3.11 LAN9303M/LAN9303Mi 72-QFN Package Pin Assignments
PIN
NUM PIN NAME
PIN
NUM PIN NAME
PIN
NUM PIN NAME
PIN
NUM PIN NAME
1 P0_IND2 19 P1_INER 37 P1_CRS 55 VDD18PLL
2 P0_IND1 20 P1_INCLK 38 P1_OUTD3/
DUPLEX_POL_1
56 TXN1
3 P0_IND0 21 P0_OUTDV 39 P1_OUTD2/
P1_MODE2
57 TXP1
4 P0_INDV 22 P0_OUTCLK 40 VDD33IO 58 VDD33A1
5 P0_INER 23 P0_COL 41 VDD18CORE 59 RXN1
6 P0_INCLK 24 P0_CRS 42 P1_OUTDV 60 RXP1
7 VDD33IO 25 P0_DUPLEX 43 P1_OUTCLK 61 VDD33A1
8 VDD18CORE 26 MDIO 44 P1_OUTD1/
P1_MODE1
62 VDD18TX1
9 P0_OUTD3/
DUPLEX_POL_0
27 MDC 45 P1_OUTD0/
P1_MODE0
63 EXRES
10 P0_OUTD2/
P0_MODE2
28 VDD33IO 46 VDD33IO 64 VDD33BIAS
11 P0_OUTD1/
P0_MODE1
29 LED5/
GPIO5/
PHYADDR_LED5P
47 TEST1 65 VDD18TX2
12 P0_OUTD0/
P0_MODE0
30 LED4/
GPIO4/
MNGT1_LED4P
48 TEST2 66 VDD33A2
13 P1_IND3 31 LED3/
GPIO3/
MNGT0_LED3P
49 EE_SDA/
SDA
67 RXP2
14 P1_IND2 32 LED2/
GPIO2/
E2PSIZE_LED2P
50 EE_SCL/
SCL
68 RXN2
15 P1_IND1 33 LED1/
GPIO1/
AMDIX2_LED1P
51 nRST 69 VDD33A2
16 P1_IND0 34 LED0/
GPIO0/
AMDIX1_LED0P
52 IRQ 70 TXP2
17 VDD33IO 35 P1_DUPLEX 53 XI 71 TXN2
18 P1_INDV 36 P1_COL 54 XO 72 P0_IND3
EXPOSED PAD
MUST BE CONNECTED TO VSS
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3.3 Buffer Types
Table 3.12 Buffer Types
BUFFER TYPE DESCRIPTION
IS Schmitt-triggered Input
O8 Output with 8mA sink and 8mA source
OD8 Open-drain output with 8mA sink
O12 Output with 12mA sink and 12mA source
OD12 Open-drain output with 12mA sink
OS12 Open-source output with 12 mA source
O16 Output with 16mA sink and 16mA source
PU 50uA (typical) internal pull-up. Unless otherwise noted in the pin description, internal pull-
ups are always enabled.
Note: Internal pull-up resistors prevent unconnected inputs from floating. Do not rely on
internal resistors to drive signals external to the device. When connected to a load
that must be pulled high, an external resistor must be added.
PD 50uA (typical) internal pull-down. Unless otherwise noted in the pin description, internal
pull-downs are always enabled.
Note: Internal pull-down resistors prevent unconnected inputs from floating. Do not rely
on internal resistors to drive signals external to the device. When connected to a
load that must be pulled low, an external resistor must be added.
AI Analog input
AIO Analog bi-directional
ICLK Crystal oscillator input pin
OCLK Crystal oscillator output pin
P Power pin
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Chapter 4 Clocking, Resets, and Power Management
4.1 Clocks
The device includes a clock module which provides generation of all system clocks as required by the
various sub-modules of the device. The device requires a fixed-frequency 25MHz clock source for use
by the internal clock oscillator and PLL. This is typically provided by attaching a 25MHz crystal to the
XI and XO pins as specified in Section 14.6, "Clock Circuit," on page 382. Optionally, this clock can
be provided by driving the XI input pin with a single-ended 25MHz clock source. If a single-ended
source is selected, the clock input must run continuously for normal device operation. The internal PLL
generates a fixed 200MHz base clock which is used to derive all sub-system clocks.
In addition to the sub-system clocks, the clock module is also responsible for generating the clocks
used for the general purpose timer and free-running clock. Refer to Chapter 11, "General Purpose
Timer & Free-Running Clock," on page 143 for additional details.
Note: Crystal specifications are provided in Table 14.20, “Crystal Specifications,” on page 382.
4.2 Resets
The device provides multiple hardware and software reset sources, which allow varying levels of the
chip to be reset. All resets can be categorized into three reset types as described in the following
sections:
Chip-Level Resets
Power-On Reset (POR)
nRST Pin Reset
Multi-Module Resets
Digital Reset (DIGITAL_RST)
Single-Module Resets
Port 2 PHY Reset
Port 1 PHY Reset
Virtual PHY Reset
The device supports the use of configuration straps to allow automatic custom configurations of various
parameters. These configuration strap values are set upon de-assertion of all chip-level resets and can
be used to easily set the default parameters of the chip at power-on or pin (nRST) reset. Refer to
Section 4.2.4, "Configuration Straps," on page 52 for detailed information on the usage of these straps.
Note: The EEPROM Loader is run upon a power-on reset, nRST pin reset, and digital reset. Refer
to Section 8.4, "EEPROM Loader," on page 121 for additional information.
Table 4.1 summarizes the effect of the various reset sources on the device. Refer to the following
sections for detailed information on each of these reset types.
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4.2.1 Chip-Level Resets
A chip-level reset event activates all internal resets, effectively resetting the entire device. Configuration
straps are latched, and the EEPROM Loader is run as a result of chip-level resets. A chip-level reset
is initiated by assertion of any of the following input events:
Power-On Reset (POR)
nRST Pin Reset
Chip-level reset/configuration completion can be determined by first polling the Byte Order Test
Register (BYTE_TEST). The returned data will be invalid until the serial interface resets are complete.
Once the returned data is the correct byte ordering value, the serial interface resets have completed.
The completion of the entire chip-level reset must then be determined by polling the Device Ready
(READY) bit of the Hardware Configuration Register (HW_CFG) until it is set. When set, the Device
Ready (READY) bit indicates that the reset has completed and the device is ready to be accessed.
With the exception of the Hardware Configuration Register (HW_CFG), Byte Order Test Register
(BYTE_TEST), and Reset Control Register (RESET_CTL), read access to any internal resources is
forbidden while the Device Ready (READY) bit is cleared. Writes to any address are invalid until the
Device Ready (READY) bit is set.
4.2.1.1 Power-On Reset (POR)
A power-on reset occurs whenever power is initially applied to the device, or if the power is removed
and reapplied to the device. This event resets all circuitry within the device. Configuration straps are
latched, and the EEPROM Loader is run as a result of this reset.
A POR reset typically takes approximately 23mS, plus an additional 91uS per byte of data loaded from
the EEPROM via the EEPROM Loader. A full EEPROM load of 64KB will complete in approximately
6.0 seconds.
4.2.1.2 nRST Pin Reset
Driving the nRST input pin low initiates a chip-level reset. This event resets all circuitry within the
device. Use of this reset input is optional, but when used, it must be driven for the period of time
Table 4.1 Reset Sources and Affected Device Circuitry
RESET SOURCE
SYSTEM
CLOCKS/RESET
SYS INTERRUPTS
SWITCH FABRIC
ETHERNET PHYS
PMI
I2C SLAVE
SMI SLAVE
EEPROM
CONTROLLER
GPIO/LED
CONTROLLER
CONFIG. STRAPS
LATCHED
EEPROM LOADER
RUN
POR XXXXXXXXXXX
nRST Pin XXXXXXXXXXX
Digital Reset XXX XXXXX X
Port 2 PHY X
Port 1 PHY X
Virtual PHY X
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specified in Section 14.5.2, "Reset and Configuration Strap Timing," on page 368. Configuration straps
are latched, and the EEPROM Loader is run as a result of this reset.
A nRST pin reset typically takes approximately 760uS, plus an additional 91uS per byte of data loaded
from the EEPROM via the EEPROM Loader. A full EEPROM load of 64KB will complete in
approximately 6.0 seconds.
Note: The nRST pin is pulled-high internally. If unused, this signal can be left unconnected. Do not
rely on internal pull-up resistors to drive signals external to the device.
Please refer to Section Table 3.8, "Miscellaneous Pins," on page 44 for a description of the nRST pin.
4.2.2 Multi-Module Resets
Multi-module resets activate multiple internal resets, but do not reset the entire chip. Configuration
straps are not latched upon multi-module resets. A multi-module reset is initiated by assertion of the
following:
Digital Reset (DIGITAL_RST)
Multi-module reset/configuration completion can be determined by first polling the Byte Order Test
Register (BYTE_TEST). The returned data will be invalid until the serial interface resets are complete.
Once the returned data is the correct byte ordering value, the serial interface resets have completed.
The completion of the entire chip-level reset must then be determined by polling the Device Ready
(READY) bit of the Hardware Configuration Register (HW_CFG) until it is set. When set, the Device
Ready (READY) bit indicates that the reset has completed and the device is ready to be accessed.
With the exception of the Hardware Configuration Register (HW_CFG), Byte Order Test Register
(BYTE_TEST), and Reset Control Register (RESET_CTL), read access to any internal resources is
forbidden while the Device Ready (READY) bit is cleared. Writes to any address are invalid until the
Device Ready (READY) bit is set.
Note: The digital reset does not reset register bits designated as NASR.
4.2.2.1 Digital Reset (DIGITAL_RST)
A digital reset is performed by setting the Digital Reset (DIGITAL_RST) bit of the Reset Control
Register (RESET_CTL). A digital reset will reset all sub-modules except the Ethernet PHYs (Port 1
PHY, Port 2 PHY, and Virtual PHY). The EEPROM Loader will automatically run following this reset.
Configuration straps are not latched as a result of a digital reset.
A digital reset typically takes approximately 760uS, plus an additional 91uS per byte of data loaded
from the EEPROM via the EEPROM Loader. A full EEPROM load of 64KB will complete in
approximately 6.0 seconds.
4.2.3 Single-Module Resets
A single-module reset will reset only the specified module. Single-module resets do not latch the
configuration straps or initiate the EEPROM Loader. A single-module reset is initiated by assertion of
the following:
Port 2 PHY Reset
Port 1 PHY Reset
Virtual PHY Reset
4.2.3.1 Port 2 PHY Reset
A Port 2 PHY reset is performed by setting the Port 2 PHY Reset (PHY2_RST) bit of the Reset Control
Register (RESET_CTL) or the Reset (PHY_RST) bit in the (x=2) Port x PHY Basic Control Register
(PHY_BASIC_CONTROL_x). Upon completion of the Port 2 PHY reset, the Port 2 PHY Reset
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(PHY2_RST) and Reset (PHY_RST) bits are automatically cleared. No other modules of the device
are affected by this reset.
In addition to the methods above, the Port 2 PHY is automatically reset after returning from a PHY
power-down mode. This reset differs in that the PHY power-down mode reset does not reload or reset
any of the PHY registers. Refer to Section 7.2.9, "PHY Power-Down Modes," on page 109 for
additional information.
Port 2 PHY reset completion can be determined by polling the Port 2 PHY Reset (PHY2_RST) bit in
the Reset Control Register (RESET_CTL) or the Reset (PHY_RST) bit in the (x=2) Port x PHY Basic
Control Register (PHY_BASIC_CONTROL_x) until it clears. Under normal conditions, these bits will
clear approximately 110uS after the Port 2 PHY reset occurrence.
Note: When using the Reset (PHY_RST) bit to reset the Port 2 PHY, register bits designated as
NASR are not reset.
Refer to Section 7.2.10, "PHY Resets," on page 109 for additional information on Port 2 PHY resets.
4.2.3.2 Port 1 PHY Reset
A Port 1 PHY reset is performed by setting the Port 1 PHY Reset (PHY1_RST) bit of the Reset Control
Register (RESET_CTL) or the Reset (PHY_RST) bit in the (x=1) Port x PHY Basic Control Register
(PHY_BASIC_CONTROL_x). Upon completion of the Port 1 PHY reset, the Port 1 PHY Reset
(PHY1_RST) and Reset (PHY_RST) bits are automatically cleared. No other modules of the device
are affected by this reset.
In addition to the methods above, the Port 1 PHY is automatically reset after returning from a PHY
power-down mode. This reset differs in that the PHY power-down mode reset does not reload or reset
any of the PHY registers. Refer to Section 7.2.9, "PHY Power-Down Modes," on page 109 for
additional information.
Port 1 PHY reset completion can be determined by polling the Port 1 PHY Reset (PHY1_RST) bit in
the Reset Control Register (RESET_CTL) or the Reset (PHY_RST) bit in the (x=1) Port x PHY Basic
Control Register (PHY_BASIC_CONTROL_x) until it clears. Under normal conditions, these bits will
clear approximately 110uS after the Port 1 PHY reset occurrence.
Note: When using the Reset (PHY_RST) bit to reset the Port 1 PHY, register bits designated as
NASR are not reset.
Refer to Section 7.2.10, "PHY Resets," on page 109 for additional information on Port 1 PHY resets.
4.2.3.3 Virtual PHY Reset
A Virtual PHY reset is performed by setting the Virtual PHY Reset (VPHY_RST) bit of the Reset
Control Register (RESET_CTL) or Reset (VPHY_RST) in the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL). No other modules of the device are affected by this reset.
Virtual PHY reset completion can be determined by polling the Virtual PHY Reset (VPHY_RST) bit in
the Reset Control Register (RESET_CTL) or the Reset (VPHY_RST) bit in the Virtual PHY Basic
Control Register (VPHY_BASIC_CTRL) until it clears. Under normal conditions, these bits will clear
approximately 1uS after the Virtual PHY reset occurrence.
Refer to Section 7.3.3, "Virtual PHY Resets," on page 113 for additional information on Virtual PHY
resets.
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4.2.4 Configuration Straps
Configuration straps allow various features of the device to be automatically configured to user defined
values. Configuration straps can be organized into two main categories: hard-straps and soft-straps.
Both hard-straps and soft-straps are latched upon Power-On Reset (POR) or pin reset (nRST). The
primary difference between these strap types is that soft-strap default values can be overridden by the
EEPROM Loader, while hard-straps cannot.
Configuration straps which have a corresponding external pin include internal resistors in order to
prevent the signal from floating when unconnected. If a particular configuration strap is connected to
a load, an external pull-up or pull-down resistor should be used to augment the internal resistor to
ensure that it reaches the required voltage level prior to latching. The internal resistor can also be
overridden by the addition of an external resistor.
Note: The system designer must guarantee that configuration strap pins meet the timing
requirements specified in Section 14.5.2, "Reset and Configuration Strap Timing," on page 368.
If configuration strap pins are not at the correct voltage level prior to being latched, the device
may capture incorrect strap values.
4.2.4.1 Soft-Straps
Soft-strap values are latched on the release of POR or nRST and are overridden by values from the
EEPROM Loader (when an EEPROM is present). These straps are used as direct configuration values
or as defaults for CPU registers. Some, but not all, soft-straps have an associated pin. Those that do
not have an associated pin have a tie off default value. All soft-strap values can be overridden by the
EEPROM Loader. Table 4.2 provides a list of all soft-straps and their associated pin or default value.
Straps which have an associated pin are also fully defined in Chapter 3, "Pin Description and
Configuration," on page 23. Refer to Section 8.4, "EEPROM Loader," on page 121 for information on
the operation of the EEPROM Loader and the loading of strap values. The use of the term “configures”
in the “Description” section of Table 4.2 means the register bit is loaded with the strap value, while the
term “Affects” means the value of the register bit is determined by the strap value and some other
condition(s).
Upon setting the Digital Reset (DIGITAL_RST) bit in the Reset Control Register (RESET_CTL) or upon
issuing a RELOAD command via the EEPROM Command Register (E2P_CMD), these straps return
to their original latched (non-overridden) values if an EEPROM is no longer attached or has been
erased. The associated pins are not re-sampled. (i.e. The value latched on the pin during the last POR
or nRST will be used, not the value on the pin during the digital reset or RELOAD command issuance).
If it is desired to re-latch the current configuration strap pin values, a POR or nRST must be issued.
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Table 4.2 Soft-Strap Configuration Strap Definitions
STRAP NAME DESCRIPTION PIN / DEFAULT
VALUE
LED_en_strap[5:0] LED Enable Straps: Configures the default value for the
LED Enable 5-0 (LED_EN[5:0]) bits of the LED
Configuration Register (LED_CFG).
1b
LED_fun_strap[1:0] LED Function Straps: Configures the default value for the
LED Function 1-0 (LED_FUN[1:0]) bits of the LED
Configuration Register (LED_CFG).
00b
auto_mdix_strap_1 Port 1 Auto-MDIX Enable Strap: Configures the default
value of the AMDIX_EN Strap State Port 1 bit of the
Hardware Configuration Register (HW_CFG).
This strap is also used in conjunction with
manual_mdix_strap_1 to configure Port 1 Auto-MDIX
functionality when the Auto-MDIX Control (AMDIXCTRL) bit
in the (x=1) Port x PHY Special Control/Status Indication
Register (PHY_SPECIAL_CONTROL_STAT_IND_x)
indicates the strap settings should be used for auto-MDIX
configuration.
Note: Not used in MII PHY, RMII PHY, or MII MAC
mode.
Refer to the respective register definition sections for
additional information.
AMDIX1_LED0P
Note 4.1
manual_mdix_strap_1 Port 1 Manual MDIX Strap: Configures MDI(0) or MDIX(1)
for Port 1 when the auto_mdix_strap_1 is low and the Auto-
MDIX Control (AMDIXCTRL) bit of the (x=1) Port x PHY
Special Control/Status Indication Register
(PHY_SPECIAL_CONTROL_STAT_IND_x) indicates the
strap settings are to be used for auto-MDIX configuration.
Note: Not used in MII PHY, RMII PHY, or MII MAC
mode.
0b
autoneg_strap_1
SQE_test_disable_strap_1
Port 1 Auto Negotiation Enable Strap: Configures the
default value of the Auto-Negotiation (PHY_AN) enable bit
of the (x=1) Port x PHY Basic Control Register
(PHY_BASIC_CONTROL_x).
This strap also may affect the default value of the following
register bits (x=1):
Speed Select LSB (PHY_SPEED_SEL_LSB) and Duplex
Mode (PHY_DUPLEX) bits of the Port x PHY Basic
Control Register (PHY_BASIC_CONTROL_x)
10BASE-T Full Duplex and 10BASE-T Half Duplex bits of
the Port x PHY Auto-Negotiation Advertisement Register
(PHY_AN_ADV_x)
PHY Mode (MODE[2:0]) bits of the Port x PHY Special
Modes Register (PHY_SPECIAL_MODES_x)
Refer to the respective register definition sections for
additional information.
Configures the default value of the SQEOFF bit of the Port
1 MII Basic Control Register (P1_MII_BASIC_CONTROL)
when in MII PHY mode. It is not used in internal PHY, RMII
PHY, or MII MAC mode.
1b when in internal
PHY mode
(P1_MODE[2:0] =
111b)
else 0b
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speed_strap_1 Port 1 Speed Select Strap: This strap configures the
default value of the Speed Select LSB bit of the Port 1 MII
Basic Control Register (P1_MII_BASIC_CONTROL).
This strap may affect the default value of the following
register bits (x=1):
Speed Select LSB (PHY_SPEED_SEL_LSB) bit of the
Port x PHY Basic Control Register
(PHY_BASIC_CONTROL_x)
PHY Mode (MODE[2:0]) bits of the Port x PHY Special
Modes Register (PHY_SPECIAL_MODES_x)
10BASE-T Full Duplex and 10BASE-T Half Duplex bits of
the Port x PHY Auto-Negotiation Advertisement Register
(PHY_AN_ADV_x)
Refer to the respective register definition sections for
additional information.
1b
duplex_strap_1
duplex_pol_strap_1
Port 1 Duplex Select Strap: This strap affects the default
value of the following register bits (x=1):
Duplex Mode (PHY_DUPLEX) bit of the Port x PHY Basic
Control Register (PHY_BASIC_CONTROL_x)
PHY Mode (MODE[2:0]) bits of the Port x PHY Special
Modes Register (PHY_SPECIAL_MODES_x)
10BASE-T Full Duplex bit of the Port x PHY Auto-
Negotiation Advertisement Register (PHY_AN_ADV_x)
Refer to the respective register definition sections for
additional information.
This strap affects the default value of the Duplex Mode bit
of the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL). It also determines the polarity
of the P1_DUPLEX pin in MII MAC mode.
1b when in internal
PHY mode
(P1_MODE[2:0] =
111b)
else
DUPLEX_POL_1
when in MII PHY,
RMII PHY, or MII
MAC mode
BP_EN_strap_1 Port 1 Backpressure Enable Strap: Configures the
default value for the Port 1 Backpressure Enable
(BP_EN_1) bit of the Port 1 Manual Flow Control Register
(MANUAL_FC_1).
1b
Table 4.2 Soft-Strap Configuration Strap Definitions (continued)
STRAP NAME DESCRIPTION PIN / DEFAULT
VALUE
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FD_FC_strap_1 Port 1 Full-Duplex Flow Control Enable Strap: This strap
is used to configure the default value of the following
register bits (x=1):
Port 1 Full-Duplex Transmit Flow Control Enable
(TX_FC_1) and Port 1 Full-Duplex Receive Flow Control
Enable (RX_FC_1) bits of the Port 1 Manual Flow Control
Register (MANUAL_FC_1)
This strap may affect the default value of the following
register bits (x=1):
Asymmetric Pause bit of the Port x PHY Auto-Negotiation
Advertisement Register (PHY_AN_ADV_x)
Refer to the respective register definition sections for
additional information.
1b
manual_FC_strap_1 Port 1 Manual Flow Control Enable Strap: Configures the
default value of the Port 1 Full-Duplex Manual Flow Control
Select (MANUAL_FC_1) bit in the Port 1 Manual Flow
Control Register (MANUAL_FC_1).
This strap affects the default value of the following register
bits (x=1):
Asymmetric Pause and Symmetric Pause bits of the Port
x PHY Auto-Negotiation Advertisement Register
(PHY_AN_ADV_x)
Note: This strap is not used in Port 1 MII PHY, RMII
PHY, or MII MAC mode. Full-duplex flow control
should be controlled manually by the host, if
desired.
0b
auto_mdix_strap_2 Port 2 Auto-MDIX Enable Strap: Configures the default
value of the AMDIX_EN Strap State Port 2 bit of the
Hardware Configuration Register (HW_CFG).
This strap is used in conjunction with manual_mdix_strap_2
to configure Port 2 Auto-MDIX functionality when the Auto-
MDIX Control (AMDIXCTRL) bit in the (x=2) Port x PHY
Special Control/Status Indication Register
(PHY_SPECIAL_CONTROL_STAT_IND_x) indicates the
strap settings should be used for auto-MDIX configuration.
Refer to the respective register definition sections for
additional information.
AMDIX2 LED1P
Note 4.1
manual_mdix_strap_2 Port 2 Manual MDIX Strap: Configures MDI(0) or MDIX(1)
for Port 2 when the auto_mdix_strap_2 is low and the Auto-
MDIX Control (AMDIXCTRL) bit of the (x=2) Port x PHY
Special Control/Status Indication Register
(PHY_SPECIAL_CONTROL_STAT_IND_x) indicates the
strap settings are to be used for auto-MDIX configuration.
0b
Table 4.2 Soft-Strap Configuration Strap Definitions (continued)
STRAP NAME DESCRIPTION PIN / DEFAULT
VALUE
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
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autoneg_strap_2 Port 2 Auto Negotiation Enable Strap: Configures the
default value of the Auto-Negotiation (PHY_AN) enable bit
in the (x=2) Port x PHY Basic Control Register
(PHY_BASIC_CONTROL_x).
This strap may also affect the default value of the following
register bits (x=2):
Speed Select LSB (PHY_SPEED_SEL_LSB) and Duplex
Mode (PHY_DUPLEX) bits of the Port x PHY Basic
Control Register (PHY_BASIC_CONTROL_x)
10BASE-T Full Duplex and 10BASE-T Half Duplex bits of
the Port x PHY Auto-Negotiation Advertisement Register
(PHY_AN_ADV_x)
PHY Mode (MODE[2:0]) bits of the Port x PHY Special
Modes Register (PHY_SPECIAL_MODES_x)
Refer to the respective register definition sections for
additional information.
1b
speed_strap_2 Port 2 Speed Select Strap: This strap affects the default
value of the following register bits (x=2):
Speed Select LSB (PHY_SPEED_SEL_LSB) bit of the
Port x PHY Basic Control Register
(PHY_BASIC_CONTROL_x)
10BASE-T Full Duplex bit and 10BASE-T Half Duplex bit
of the Port x PHY Auto-Negotiation Advertisement
Register (PHY_AN_ADV_x)
PHY Mode (MODE[2:0]) bits of the Port x PHY Special
Modes Register (PHY_SPECIAL_MODES_x)
Refer to the respective register definition sections for
additional information.
1b
duplex_strap_2 Port 2 Duplex Select Strap: This strap affects the default
value of the following register bits (x=2):
Duplex Mode (PHY_DUPLEX) bit of the Port x PHY Basic
Control Register (PHY_BASIC_CONTROL_x)
10BASE-T Full Duplex bit of the Port x PHY Auto-
Negotiation Advertisement Register (PHY_AN_ADV_x)
PHY Mode (MODE[2:0]) bits of the Port x PHY Special
Modes Register (PHY_SPECIAL_MODES_x)
Refer to the respective register definition sections for
additional information.
1b
BP_EN_strap_2 Port 2 Backpressure Enable Strap: Configures the
default value for the Port 2 Backpressure Enable
(BP_EN_2) bit of the Port 2 Manual Flow Control Register
(MANUAL_FC_2).
1b
Table 4.2 Soft-Strap Configuration Strap Definitions (continued)
STRAP NAME DESCRIPTION PIN / DEFAULT
VALUE
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FD_FC_strap_2 Port 2 Full-Duplex Flow Control Enable Strap: This strap
is used to configure the default value of the following
register bits:
Port 2 Full-Duplex Transmit Flow Control Enable
(TX_FC_2) and Port 2 Full-Duplex Receive Flow Control
Enable (RX_FC_2) bits of the Port 2 Manual Flow Control
Register (MANUAL_FC_2).
This strap may affect the default value of the following
register bits (x=2):
Asymmetric Pause bit of the Port x PHY Auto-Negotiation
Advertisement Register (PHY_AN_ADV_x)
Refer to the respective register definition sections for
additional information.
1b
manual_FC_strap_2 Port 2 Manual Flow Control Enable Strap: Configures the
default value of the Port 2 Full-Duplex Manual Flow Control
Select (MANUAL_FC_2) bit in the Port 2 Manual Flow
Control Register (MANUAL_FC_2).
This strap affects the default value of the following register
bits (x=2):
Asymmetric Pause and Symmetric Pause bits of the Port
x PHY Auto-Negotiation Advertisement Register
(PHY_AN_ADV_x).
0b
speed_strap_0 Port 0 (External MII) Speed Select Strap: This strap
affects the default value of the following bits in the Virtual
PHY Auto-Negotiation Link Partner Base Page Ability
Register (VPHY_AN_LP_BASE_ABILITY):
100BASE-X Full Duplex
100BASE-X Half Duplex
10BASE-T Full Duplex
10BASE-T Half Duplex
Refer to Section 13.2.6.6 and Table 13.7 for more
information.
This strap also configures the speed for Port 0 when Virtual
Auto-Negotiation fails. Refer to Section 7.3.1.1, "Parallel
Detection," on page 112 for additional information.
1b
Table 4.2 Soft-Strap Configuration Strap Definitions (continued)
STRAP NAME DESCRIPTION PIN / DEFAULT
VALUE
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duplex_pol_strap_0 Port 0 (External MII) Duplex Polarity Strap: This strap
determines the polarity of the P0_DUPLEX pin in MII MAC
mode and affects the default value of the following bits in
the Virtual PHY Auto-Negotiation Link Partner Base Page
Ability Register (VPHY_AN_LP_BASE_ABILITY):
100BASE-X Full Duplex
100BASE-X Half Duplex
10BASE-T Full Duplex
10BASE-T Half Duplex
Refer to Section 13.2.6.6 and Table 13.7 for more
information.
DUPLEX_POL_0
BP_EN_strap_0 Port 0 (External MII) Backpressure Enable Strap:
Configures the default value of the Port 0 Backpressure
Enable (BP_EN_0) bit of the Port 0 Manual Flow Control
Register (MANUAL_FC_0).
1b
FD_FC_strap_0 Port 0 (External MII) Full-Duplex Flow Control Enable
Strap: Configures the default value of the Port 0 Transmit
Flow Control Enable (TX_FC_0) and Port 0 Receive Flow
Control Enable (RX_FC_0) bits in the Port 0 Manual Flow
Control Register (MANUAL_FC_0).
This strap affects the default value of the following register
bits:
Asymmetric Pause and Pause bits of the Virtual PHY
Auto-Negotiation Link Partner Base Page Ability Register
(VPHY_AN_LP_BASE_ABILITY)
1b
manual_FC_strap_0 Port 0 (External MII) Manual Flow Control Enable Strap:
This strap affects the default value of the following register
bits:
Port 0 Full-Duplex Manual Flow Control Select
(MANUAL_FC_0) bit in the Port 0 Manual Flow Control
Register (MANUAL_FC_0)
Asymmetric Pause and Symmetric Pause bits of the
Virtual PHY Auto-Negotiation Advertisement Register
(VPHY_AN_ADV)
Refer to the respective register definition sections for
additional information.
Note: In MAC mode, this strap is not used. In this mode,
the Virtual PHY is not applicable, and full-duplex
flow control must be controlled manually by the
host, based upon the external PHYs Auto-
negotiation results.
0b
SQE_test_disable_strap_0 SQE Heartbeat Disable Strap: Configures the default
value of the SQEOFF bit of the Virtual PHY Special
Control/Status Register
(VPHY_SPECIAL_CONTROL_STATUS) when in MII PHY
mode. It is not used in RMII PHY or MII MAC modes.
0b
Table 4.2 Soft-Strap Configuration Strap Definitions (continued)
STRAP NAME DESCRIPTION PIN / DEFAULT
VALUE
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
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4.2.4.2 Hard-Straps
Hard-straps are latched upon Power-On Reset (POR) or pin reset (nRST) only. Unlike soft-straps,
hard-straps always have an associated pin and cannot be overridden by the EEPROM Loader. These
straps are used as either direct configuration values or as register defaults. Table 4.3 provides a list of
all hard-straps and their associated pins. These straps, along with their pin assignments are also
defined in Chapter 3, "Pin Description and Configuration," on page 23.
Table 4.3 Hard-Strap Configuration Strap Definitions
STRAP NAME DESCRIPTION PIN(S)
mngt_mode_strap[1:0] Serial Management Mode Strap: Configures the default
serial management mode.
00 = RESERVED
01 = SMI Managed Mode
10 = I2C Managed Mode
11 = RESERVED
Refer to Section 2.3, "Modes of Operation," on page 19 for
additional information on the various modes of the device.
MNGT1_LED4P :
MNGT0_LED3P
Note 4.1
eeprom_size_strap EEPROM Size Strap: Configures the EEPROM size range
as specified in Section 8.3, "I2C Master EEPROM
Controller," on page 115.
E2PSIZE_LED2P
Note 4.1
P0_mode_strap[1:0] Port 0 Mode Strap: Configures the default mode of
operation for Port 0.
00 = MII MAC Mode
01 = MII PHY Mode
10 = RMII PHY Mode
11 = RESERVED
These operating modes result from the following mapping:
Refer to Section 2.3, "Modes of Operation," on page 19 for
additional information on the various modes of the device.
P0_MODE2 :
P0_MODE1 :
P0_MODE0
P0_rmii_clock_dir_strap Port 0 RMII Clock Direction Strap: Configures the default
value of the RMII Clock Direction bit of the Virtual PHY
Special Control/Status Register
(VPHY_SPECIAL_CONTROL_STATUS).
Note: The value of this strap is the inverse of the
P0_MODE1 pin.
P0_MODE1
P0_clock_strength_strap Port 0 Clock Strength Strap: Configures the default value
of the RMII/Turbo MII Clock Strength bit of the Virtual PHY
Special Control/Status Register
(VPHY_SPECIAL_CONTROL_STATUS).
P0_MODE0
P0_MODE[2:0] P0_mode_strap[1:0]
000 00 (MII MAC)
001, 010, or 011 01 (MII PHY)
100, 101, or 110 10 (RMII PHY)
111 RESERVED
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Note 4.1 This pin has shared strap functionality. Refer to Ta b l e 4 . 4 for details.
turbo_mii_enable_strap_0 Port 0 Turbo MII Enable Strap: Configures the default
value of the Turbo MII Enable bit of the Virtual PHY Special
Control/Status Register
(VPHY_SPECIAL_CONTROL_STATUS) when in MII PHY
mode.
P0_MODE1
P1_mode_strap[1:0] Port 1 Mode Strap: Configures the default mode of
operation for Port 1.
00 = MII MAC Mode
01 = MII PHY Mode
10 = RMII PHY Mode
11 = Internal PHY
These operating modes result from the following mapping:
Refer to Section 2.3, "Modes of Operation," on page 19 for
additional information on the various modes of the device.
P1_MODE2 :
P1_MODE1 :
P1_MODE0
P1_rmii_clock_dir_strap Port 1 RMII Clock Direction Strap: Configures the default
value of the RMII Clock Direction bit of the Port 1 MII Basic
Control Register (P1_MII_BASIC_CONTROL).
Note: The value of this strap is the inverse of the
P1_MODE1 pin.
P1_MODE1
P1_clock_strength_strap Port 1 Clock Strength Strap: Configures the default value
of the RMII/Turbo MII Clock Strength bit of the Port 1 MII
Basic Control Register (P1_MII_BASIC_CONTROL).
P1_MODE0
turbo_mii_enable_strap_1 Port 1 Turbo MII Enable Strap: Configures the default
value of the Turbo MII Enable bit of the Port 1 MII Basic
Control Register (P1_MII_BASIC_CONTROL) when in MII
PHY MODE.
P1_MODE1
phy_addr_sel_strap PHY Address Select Strap: Configures the default MII
management address values for the PHYs and Virtual PHY
as detailed in Section 7.1.1, "PHY Addressing," on page 96.
PHYADDR_LED5P
Note 4.1
led_pol_strap[5:0] LED Polarity Strap: Configures the default polarity for
each of the LEDs when they are an open-drain or open-
source output.
0 = The LED is set as active high, since it is assumed
that a LED to ground is used as the pull-down.
1 = The LED is set as active low, since it is assumed
that a LED to VDD is used as the pull-up.
PHYADDR_LED5P :
MNGT1_LED4P :
MNGT0_LED3P :
E2PSIZE_LED2P :
AMDIX2_LED1P :
AMDIX1_LED0P
Table 4.3 Hard-Strap Configuration Strap Definitions (continued)
STRAP NAME DESCRIPTION PIN(S)
P1_MODE[2:0] P1_mode_strap[1:0]
000 00 (MII MAC)
001, 010, or 011 01 (MII PHY)
100, 101, or 110 10 (RMII PHY)
111 11 (internal PHY)
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4.3 Power Management
The Port 1 and Port 2 PHYs support several power management and wakeup features.
4.3.1 Port 1 & 2 PHY Power Management
The Port 1 & 2 PHYs provide independent general power-down and energy-detect power-down modes
which reduce PHY power consumption. General power-down mode provides power savings by
powering down the entire PHY, except the PHY management control interface. General power-down
mode must be manually enabled and disabled as described in Section 7.2.9.1, "PHY General Power-
Down," on page 109.
In energy-detect power-down mode, the PHY will resume from power-down when energy is seen on
the cable (typically from link pulses). If the ENERGYON interrupt (INT7) of either PHYs Port x PHY
Interrupt Mask Register (PHY_INTERRUPT_MASK_x) is unmasked, then the corresponding PHY will
generate an interrupt. These interrupts are reflected in the Interrupt Status Register (INT_STS) Port 2
PHY Interrupt Event (PHY_INT2) for the Port 2 PHY, and Port 1 PHY Interrupt Event (PHY_INT1) for
the Port 1 PHY. These interrupts can be used to trigger the IRQ interrupt output pin, as described in
Section 5.2.2, "Ethernet PHY Interrupts," on page 64. Refer to Section 7.2.9.2, "PHY Energy Detect
Power-Down," on page 109 for details on the operation and configuration of the PHY energy-detect
power-down mode.
Note: The Port 1 PHY is set into general power-down mode when Port 1 is configured to MII PHY,
RMII PHY, or MII MAC mode.
Table 4.4 PIN/Shared Strap Mapping
PIN STRAP NAME 1 STRAP NAME 2
PHYADDR_LED5P phy_addr_sel_strap led_pol_strap[5]
MNGT1_LED4P mngt_mode_strap[1] led_pol_strap[4]
MNGT0_LED3P mngt_mode_strap[0] led_pol_strap[3]
E2PSIZE_LED2P eeprom_size_strap led_pol_strap[2]
AMDIX2_LED1P auto_mdix_strap_2 led_pol_strap[1]
AMDIX1_LED0P auto_mdix_strap_1 led_pol_strap[0]
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Chapter 5 System Interrupts
5.1 Functional Overview
This chapter describes the system interrupt structure. The device provides a multi-tier programmable
interrupt structure which is controlled by the System Interrupt Controller. The programmable system
interrupts are generated internally by the various sub-modules and can be configured to generate a
single external host interrupt via the IRQ interrupt output pin. The programmable nature of the host
interrupt provides the user with the ability to optimize performance dependent upon the application
requirements. The IRQ interrupt buffer type, polarity, and de-assertion interval are modifiable. The IRQ
interrupt can be configured as an open-drain output to facilitate the sharing of interrupts with other
devices. All internal interrupts are maskable and capable of triggering the IRQ interrupt.
5.2 Interrupt Sources
The device is capable of generating the following interrupt types:
Switch Fabric Interrupts (Buffer Manager, Switch Engine, and Port 2,1,0 MACs)
Ethernet PHY Interrupts (Port 1,2 PHYs)
GPIO Interrupts (GPIO[5:0])
General Purpose Timer Interrupt (GPT)
Software Interrupt (General Purpose)
Device Ready Interrupt
All interrupts are accessed and configured via registers arranged into a multi-tier, branch-like structure,
as shown in Figure 5.1. At the top level of the interrupt structure are the Interrupt Status Register
(INT_STS), Interrupt Enable Register (INT_EN), and Interrupt Configuration Register (IRQ_CFG).
The Interrupt Status Register (INT_STS) and Interrupt Enable Register (INT_EN) aggregate and
enable/disable all interrupts from the various sub-modules, combining them together to create the IRQ
interrupt. These registers provide direct interrupt access/configuration to the General Purpose Timer,
software, and device ready interrupts. These interrupts can be monitored, enabled/disabled, and
cleared, directly within these two registers. In addition, interrupt event indications are provided for the
Switch Fabric, Port 1 & 2 Ethernet PHYs, and GPIO interrupts. These interrupts differ in that the
interrupt sources are generated and cleared in other sub-block registers. The Interrupt Status Register
(INT_STS) does not provide details on what specific event within the sub-module caused the interrupt,
and requires the software to poll an additional sub-module interrupt register (as shown in Figure 5.1)
to determine the exact interrupt source and clear it. For interrupts which involve multiple registers, only
after the interrupt has been serviced and cleared at its source will it be cleared in the Interrupt Status
Register (INT_STS).
The Interrupt Configuration Register (IRQ_CFG) is responsible for enabling/disabling the IRQ interrupt
output pin as well as configuring its properties. This register allows the modification of the IRQ pin
buffer type, polarity, and de-assertion interval. The de-assertion timer guarantees a minimum interrupt
de-assertion period for the IRQ output and is programmable via the Interrupt De-assertion Interval
(INT_DEAS) field of the Interrupt Configuration Register (IRQ_CFG). A setting of all zeros disables the
de-assertion timer. The de-assertion interval starts when the IRQ pin de-asserts, regardless of the
reason.
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The following sections detail each category of interrupts and their related registers. Refer to
Chapter 13, "Register Descriptions," on page 148 for bit-level definitions of all interrupt registers.
Figure 5.1 Functional Interrupt Register Hierarchy
INT_CFG
INT_STS
INT_EN
Top Level Interrupt Registers
(System CSRs)
PHY_INTERRUPT_SOURCE_2
PHY_INTERRUPT_MASK_2
Port 2 PHY Interrupt Registers
PHY_INT2 bit
of INT_STS register
PHY_INTERRUPT_SOURCE_1
PHY_INTERRUPT_MASK_1
Port 1 PHY Interrupt Registers
PHY_INT1 bit
of INT_STS register
SW_IMR
SW_IPR
Switch Fabric Interrupt Registers
SWITCH_INT bit
of INT_STS register
BM_IMR
BM_IPR
Buffer Manager Interrupt Registers
BM bit
of SW_IPR register
SWE_IMR
SWE_IPR
Switch Engine Interrupt Registers
SWE bit
of SW_IPR register
MAC_IMR_[2,1,0]
MAC_IPR_[2,1,0]
Port [2,1,0] MAC Interrupt Registers
MAC_[2,1,0] bits
of SW_IPR register
GPIO_INT_STS_EN
GPIO Interrupt Register
GPIO bit
of INT_STS register
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5.2.1 Switch Fabric Interrupts
Multiple Switch Fabric interrupt sources are provided in a three-tiered register structure as shown in
Figure 5.1. The top-level Switch Fabric Interrupt Event (SWITCH_INT) bit of the Interrupt Status
Register (INT_STS) provides indication that a Switch Fabric interrupt event occurred in the Switch
Global Interrupt Pending Register (SW_IPR).
The Switch Engine Interrupt Pending Register (SWE_IPR) and Switch Engine Interrupt Mask Register
(SWE_IMR) provide status and enabling/disabling of all Switch Fabric sub-modules interrupts (Buffer
Manager, Switch Engine, and Port 2,1,0 MACs).
The low-level Switch Fabric sub-module interrupt pending and mask registers of the Buffer Manager,
Switch Engine, and Port 2,1,0 MACs provide multiple interrupt sources from their respective sub-
modules. These low-level registers provide the following interrupt sources:
Buffer Manager (Buffer Manager Interrupt Mask Register (BM_IMR) and Buffer Manager Interrupt
Pending Register (BM_IPR))
—Status B Pending
—Status A Pending
Switch Engine (Switch Engine Interrupt Mask Register (SWE_IMR) and Switch Engine Interrupt
Pending Register (SWE_IPR))
—Interrupt Pending
Port 2,1,0 MACs (Port x MAC Interrupt Mask Register (MAC_IMR_x) and Port x MAC Interrupt
Pending Register (MAC_IPR_x))
—No currently supported interrupt sources. These registers are reserved for future use.
In order for a Switch Fabric interrupt event to trigger the external IRQ interrupt pin, the following must
be configured:
The desired Switch Fabric sub-module interrupt event must be enabled in the corresponding mask
register (Buffer Manager Interrupt Mask Register (BM_IMR) for the Buffer Manager, Switch Engine
Interrupt Mask Register (SWE_IMR) for the Switch Engine, and/or Port x MAC Interrupt Mask
Register (MAC_IMR_x) for the Port 2,1,0 MACs)
The desired Switch Fabric sub-module interrupt event must be enabled in the Switch Global
Interrupt Mask Register (SW_IMR)
Switch Fabric Interrupt Event Enable (SWITCH_INT_EN) bit of the Interrupt Enable Register
(INT_EN) must be set
IRQ output must be enabled via the IRQ Enable (IRQ_EN) bit of the Interrupt Configuration
Register (IRQ_CFG)
For additional details on the Switch Fabric interrupts, refer to Section 6.6, "Switch Fabric Interrupts,"
on page 95.
5.2.2 Ethernet PHY Interrupts
The Port 1 and Port 2 PHYs each provide a set of identical interrupt sources. The top-level Port 1 PHY
Interrupt Event (PHY_INT1) and Port 2 PHY Interrupt Event (PHY_INT2) bits of the Interrupt Status
Register (INT_STS) provide indication that a PHY interrupt event occurred in the respective Port x PHY
Interrupt Source Flags Register (PHY_INTERRUPT_SOURCE_x).
Port 1 and Port 2 PHY interrupts are enabled/disabled via their respective Port x PHY Interrupt Mask
Register (PHY_INTERRUPT_MASK_x). The source of a PHY interrupt can be determined and cleared
via the Port x PHY Interrupt Source Flags Register (PHY_INTERRUPT_SOURCE_x). The Port 1 and
Port 2 PHYs are each capable of generating unique interrupts based on the following events:
ENERGYON Activated
Auto-Negotiation Complete
Remote Fault Detected
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Link Down (Link Status Negated)
Auto-Negotiation LP Acknowledge
Parallel Detection Fault
Auto-Negotiation Page Received
In order for a Port 1 or Port 2 interrupt event to trigger the external IRQ interrupt pin, the desired PHY
interrupt event must be enabled in the corresponding Port x PHY Interrupt Mask Register
(PHY_INTERRUPT_MASK_x), the Port 1 PHY Interrupt Event (PHY_INT1) and/or Port 2 PHY Interrupt
Event (PHY_INT2) bits of the Interrupt Enable Register (INT_EN) must be set, and IRQ output must
be enabled via the IRQ Enable (IRQ_EN) bit of the Interrupt Configuration Register (IRQ_CFG). For
additional details on the Ethernet PHY interrupts, refer to Section 7.2.8.1, "PHY Interrupts," on
page 108.
5.2.3 GPIO Interrupts
Each GPIO[5:0] is provided with its own interrupt. The top-level GPIO Interrupt Event (GPIO) bit of the
Interrupt Status Register (INT_STS) provides indication that a GPIO interrupt event occurred in the
General Purpose I/O Interrupt Status and Enable Register (GPIO_INT_STS_EN). The General
Purpose I/O Interrupt Status and Enable Register (GPIO_INT_STS_EN) provides enabling/disabling
and status of each GPIO[5:0] interrupt.
In order for a GPIO interrupt event to trigger the external IRQ interrupt pin, the desired GPIO interrupt
must be enabled in the General Purpose I/O Interrupt Status and Enable Register
(GPIO_INT_STS_EN), the GPIO Interrupt Event Enable (GPIO_EN) bit of the Interrupt Enable Register
(INT_EN) must be set, and IRQ output must be enabled via the IRQ Enable (IRQ_EN) bit of the
Interrupt Configuration Register (IRQ_CFG). For additional details on the GPIO interrupts, refer to
Section 12.2.1, "GPIO Interrupts," on page 144.
5.2.4 General Purpose Timer Interrupt
A GP Timer (GPT_INT) interrupt is provided in the top-level Interrupt Status Register (INT_STS) and
Interrupt Enable Register (INT_EN). This interrupt is issued when the General Purpose Timer
Configuration Register (GPT_CFG) wraps past zero to FFFFh, and is cleared when the GP Timer
(GPT_INT) bit of the Interrupt Status Register (INT_STS) is written with 1.
In order for a General Purpose Timer interrupt event to trigger the external IRQ interrupt pin, the GPT
must be enabled via the General Purpose Timer Enable (TIMER_EN) bit of the General Purpose Timer
Configuration Register (GPT_CFG), the GP Timer Interrupt Enable (GPT_INT_EN) bit of the Interrupt
Enable Register (INT_EN) must be set, and IRQ output must be enabled via the IRQ Enable (IRQ_EN)
bit of the Interrupt Configuration Register (IRQ_CFG). For additional details on the General Purpose
Timer, refer to Section 11.1, "General Purpose Timer," on page 143.
5.2.5 Software Interrupt
A general purpose software interrupt is provided in the top level Interrupt Status Register (INT_STS)
and Interrupt Enable Register (INT_EN). The Software Interrupt (SW_INT) bit of the Interrupt Status
Register (INT_STS) is generated when the Software Interrupt Enable (SW_INT_EN) bit of the Interrupt
Enable Register (INT_EN) is set. This interrupt provides an easy way for software to generate an
interrupt, and is designed for general software usage.
5.2.6 Device Ready Interrupt
A device ready interrupt is provided in the top-level Interrupt Status Register (INT_STS) and Interrupt
Enable Register (INT_EN). The Device Ready (READY) bit of the Interrupt Status Register (INT_STS)
indicates that the device is ready to be accessed after a power-up or reset condition. Writing a 1 to
this bit in the Interrupt Status Register (INT_STS) will clear it.
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In order for a device ready interrupt event to trigger the external IRQ interrupt pin, the Device Ready
Enable (READY_EN) bit of the Interrupt Enable Register (INT_EN) must be set, and IRQ output must
be enabled via the IRQ Enable (IRQ_EN) bit of the Interrupt Configuration Register (IRQ_CFG).
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Chapter 6 Switch Fabric
6.1 Functional Overview
At the core of the device is the high performance, high efficiency 3 port Ethernet Switch Fabric. The
Switch Fabric contains a 3 port VLAN layer 2 Switch Engine that supports untagged, VLAN tagged,
and priority tagged frames. The Switch Fabric provides an extensive feature set which includes
spanning tree protocol support, multicast packet filtering and Quality of Service (QoS) packet
prioritization by VLAN tag, destination address, port default value or DIFFSERV/TOS, allowing for a
range of prioritization implementations. 32K of buffer RAM allows for the storage of multiple packets
while forwarding operations are completed, and a 512 entry forwarding table provides room for MAC
address forwarding tables. Each port is allocated a cluster of 4 dynamic QoS queues which allow each
queue size to grow and shrink with traffic, effectively utilizing all available memory. This memory is
managed dynamically via the Buffer Manager block within the Switch Fabric. All aspects of the Switch
Fabric are managed via the Switch Fabric configuration and status registers (CSR), which are indirectly
accessible via the system control and status registers.
The Switch Fabric consists of four major block types:
Switch Fabric CSRs - These registers provide access to various Switch Fabric parameters for
configuration and monitoring.
10/100 Ethernet MACs - A total of three MACs are included in the Switch Fabric which provide
basic 10/100 Ethernet functionality for each Switch Fabric port.
Switch Engine (SWE) - This block is the core of the Switch Fabric and provides VLAN layer 2
switching for all three switch ports.
Buffer Manager (BM) - This block provides control of the free buffer space, transmit queues, and
scheduling.
Refer to Figure 2.1 Internal Block Diagram on page 16 for details on the interconnection of the Switch
Fabric blocks within the device.
6.2 Switch Fabric CSRs
The Switch Fabric CSRs provide register level access to the various parameters of the Switch Fabric.
Switch Fabric related registers can be classified into two main categories based upon their method of
access: direct and indirect.
The directly accessible Switch Fabric registers are part of the main system CSRs and are detailed in
Section 13.2.4, "Switch Fabric," on page 164. These registers provide Switch Fabric manual flow
control (Ports 0-2), data/command registers (for access to the indirect Switch Fabric registers), and
switch MAC address configuration.
The indirectly accessible Switch Fabric registers reside within the Switch Fabric and must be accessed
indirectly via the Switch Fabric CSR Interface Data Register (SWITCH_CSR_DATA) and Switch Fabric
CSR Interface Command Register (SWITCH_CSR_CMD), or the set of Switch Fabric CSR Interface
Direct Data Registers (SWITCH_CSR_DIRECT_DATA). The indirectly accessible Switch Fabric CSRs
provide full access to the many configurable parameters of the Switch Engine, Buffer Manager, and
each switch port. The Switch Fabric CSRs are detailed in Section 13.4, "Switch Fabric Control and
Status Registers," on page 228.
For detailed descriptions of all Switch Fabric related registers, refer to Chapter 13, "Register
Descriptions," on page 148.
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6.2.1 Switch Fabric CSR Writes
To perform a write to an individual Switch Fabric register, the desired data must first be written into the
Switch Fabric CSR Interface Data Register (SWITCH_CSR_DATA). The write cycle is initiated by
performing a single write to the Switch Fabric CSR Interface Command Register
(SWITCH_CSR_CMD) with the CSR Busy (CSR_BUSY) bit set, the CSR Address (CSR_ADDR[15:0])
field set to the desired register address, the Read/Write (R_nW) bit cleared, the Auto Increment
(AUTO_INC) and Auto Decrement (AUTO_DEC) fields cleared, and the desired CSR Byte Enable
(CSR_BE[3:0]) bits selected. The completion of the write cycle is indicated by the clearing of the CSR
Busy (CSR_BUSY) bit.
A second write method may be used which utilizes the auto increment/decrement function of the
Switch Fabric CSR Interface Command Register (SWITCH_CSR_CMD) for writing sequential register
addresses. When using this method, the Switch Fabric CSR Interface Command Register
(SWITCH_CSR_CMD) must first be written with the Auto Increment (AUTO_INC) or Auto Decrement
(AUTO_DEC) bit set, the CSR Address (CSR_ADDR[15:0]) field written with the desired register
address, the Read/Write (R_nW) bit cleared, and the desired CSR byte enable bits selected (typically
all set). The write cycles are then initiated by writing the desired data into the Switch Fabric CSR
Interface Data Register (SWITCH_CSR_DATA). The completion of the write cycle is indicated by the
clearing of the CSR Busy (CSR_BUSY) bit, at which time the address in the Switch Fabric CSR
Interface Command Register (SWITCH_CSR_CMD) is incremented or decremented accordingly. The
user may then initiate a subsequent write cycle by writing the desired data into the Switch Fabric CSR
Interface Data Register (SWITCH_CSR_DATA).
The third write method is to use the direct data range write function. Writes within the Switch Fabric
CSR Interface Direct Data Registers (SWITCH_CSR_DIRECT_DATA) address range automatically set
the appropriate register address, set all four CSR Byte Enable (CSR_BE[3:0]) bits, clears the
Read/Write (R_nW) bit, and set the CSR Busy (CSR_BUSY) bit of the Switch Fabric CSR Interface
Command Register (SWITCH_CSR_CMD). The completion of the write cycle is indicated by the
clearing of the CSR Busy (CSR_BUSY) bit. Since the address range of the Switch Fabric CSRs
exceeds that of the Switch Fabric CSR Interface Direct Data Registers
(SWITCH_CSR_DIRECT_DATA) address range, a sub-set of the Switch Fabric CSRs are mapped to
the Switch Fabric CSR Interface Direct Data Registers (SWITCH_CSR_DIRECT_DATA) address range
as detailed in Table 13.4, “Switch Fabric CSR to SWITCH_CSR_DIRECT_DATA Address Range Map,”
on page 176.
Figure 6.1 illustrates the process required to perform a Switch Fabric CSR write.
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6.2.2 Switch Fabric CSR Reads
To perform a read of an individual Switch Fabric register, the read cycle must be initiated by performing
a single write to the Switch Fabric CSR Interface Command Register (SWITCH_CSR_CMD) with the
CSR Busy (CSR_BUSY) bit set, the CSR Address (CSR_ADDR[15:0]) field set to the desired register
address, the Read/Write (R_nW) bit set, and the Auto Increment (AUTO_INC) and Auto Decrement
(AUTO_DEC) fields cleared. Valid data is available for reading when the CSR Busy (CSR_BUSY) bit
is cleared, indicating that the data can be read from the Switch Fabric CSR Interface Data Register
(SWITCH_CSR_DATA).
A second read method may be used which utilizes the auto increment/decrement function of the Switch
Fabric CSR Interface Command Register (SWITCH_CSR_CMD) for reading sequential register
addresses. When using this method, the Switch Fabric CSR Interface Command Register
(SWITCH_CSR_CMD) must first be written with the Auto Increment (AUTO_INC) or Auto Decrement
(AUTO_DEC) bit set, the CSR Address (CSR_ADDR[15:0]) field written with the desired register
address, and the Read/Write (R_nW) bit set. The completion of a read cycle is indicated by the clearing
of the CSR Busy (CSR_BUSY) bit, at which time the data can be read from the Switch Fabric CSR
Interface Data Register (SWITCH_CSR_DATA). When the data is read, the address in the Switch
Fabric CSR Interface Command Register (SWITCH_CSR_CMD) is incremented or decremented
accordingly, and another read cycle is started automatically. The user should clear the Auto Increment
(AUTO_INC) and Auto Decrement (AUTO_DEC) bits before reading the last data to avoid an
unintended read cycle.
Figure 6.2 illustrates the process required to perform a Switch Fabric CSR read.
Figure 6.1 Switch Fabric CSR Write Access Flow Diagram
Idle
Write Data
Register
Write
Command
Register
Read
Command
Register
CSR_BUSY = 0
CSR Write
CSR_BUSY = 1
Idle
Write Data
Register
Write
Command
Register
Read
Command
Register
CSR_BUSY = 0
CSR Write Auto
Increment /
Decrement
CSR_BUSY = 1
Idle
Write
Direct
Data
Register
Range
Read
Command
RegisterCSR_BUSY = 0
CSR Write Direct
Address
CSR_BUSY = 1
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6.2.3 Flow Control Enable Logic
Each Switch Fabric port (0,1,2) is provided with two flow control enable inputs per port, one for
transmission and one for reception. Flow control on transmission allows the transmitter to generate
back pressure in half-duplex mode, and pause packets in full-duplex. Flow control in reception enables
the reception of pause packets to pause transmissions.
The state of these enables is based on the state of the port’s duplex and Auto-negotiation settings and
the values of the corresponding Manual Flow Control register (Port 1 Manual Flow Control Register
(MANUAL_FC_1), Port 2 Manual Flow Control Register (MANUAL_FC_2), or Port 0 Manual Flow
Control Register (MANUAL_FC_0)). Table 6.1 details the Switch Fabric flow control enable logic.
When in half-duplex mode, the transmit flow control (back pressure) enable is determined directly by
the BP_EN_x bit of the port’s manual flow control register. When Auto-negotiation is disabled, or the
MANUAL_FC_x bit of the port’s manual flow control register is set, the switch port flow control enables
during full-duplex are determined by the TX_FC_x and RX_FC_x bits of the port’s manual flow control
Figure 6.2 Switch Fabric CSR Read Access Flow Diagram
Idle
Write
Command
Register
Read
Command
Register
Read Data
Register
CSR_BUSY = 0
CSR Read
CSR_BUSY = 1
Idle
Write
Command
Register
Read
Command
Register
CSR_BUSY = 0
CSR Read Auto
Increment /
Decrement
CSR_BUSY = 1
Write
Command
Register
Read Data
Register
last
data?
Yes
No Read Data
Register
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register. When Auto-negotiation is enabled and the MANUAL_FC_x bit is cleared, the switch port flow
control enables during full-duplex are determined by Auto-negotiation.
Note: The flow control values in the Port x PHY Auto-Negotiation Advertisement Register
(PHY_AN_ADV_x) and Virtual PHY Auto-Negotiation Advertisement Register
(VPHY_AN_ADV) are not affected by the values of the manual flow control register. Refer to
Section 7.2.5.1, "PHY Pause Flow Control," on page 106 and Section 7.3.1.3, "Virtual PHY
Pause Flow Control," on page 112 for additional information on PHY and Virtual PHY flow
control settings respectively.
Note 6.1 If Auto-negotiation is enabled and complete, but the link partner is not Auto-negotiation
capable, half-duplex is forced via the parallel detect function.
Note 6.2 For the Port 1 and Port 2 PHYs, these are the bits from the Port x PHY Auto-Negotiation
Advertisement Register (PHY_AN_ADV_x) and Port x PHY Auto-Negotiation Link Partner
Base Page Ability Register (PHY_AN_LP_BASE_ABILITY_x). For the Virtual PHY, these
are the local/partner swapped outputs from the bits in the Virtual PHY Auto-Negotiation
Advertisement Register (VPHY_AN_ADV) and Virtual PHY Auto-Negotiation Link Partner
Base Page Ability Register (VPHY_AN_LP_BASE_ABILITY). Refer to Section 7.3.1,
"Virtual PHY Auto-Negotiation," on page 110 for more information.
Table 6.1 Switch Fabric Flow Control Enable Logic
CASE
MANUAL_FC_X
AN ENABLE
AN COMPLETE
LP AN ABLE
DUPLEX
AN PAUSE
ADVERTISEMENT
(Note 6.2)
AN ASYM PAUSE
ADVERTISEMENT
(Note 6.2)
LP PAUSE
ABILITY
(Note 6.2)
LP ASYM PAUSE
ABILITY
(Note 6.2)
RX FLOW CONTROL
ENABLE
TX FLOW CONTROL
ENABLE
-1XXXHalf XXXX0
BP_EN_x
-X0XXHalf XXXX0
BP_EN_x
-1XXXFull XXXX
RX_FC_x TX_FC_x
-X0XXFull XXXX
RX_FC_x TX_FC_x
10 1 0X X XXXX0 0
20 1 10Half (Note 6.1)XXXX0
BP_EN_x
30 1 11Half XXXX0
BP_EN_x
40 1 11Full 0 0 X X 0 0
50 1 11Full 0 1 0 X 0 0
60 1 11Full 011000
70 1 11Full 011101
80 1 11Full 1 0 0 X 0 0
90 1 11Full 1X1X11
10 0 1 11Full 110000
11 0 1 11Full 110110
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Per Ta b l e 6 . 1, the following cases are possible:
Case 1 - Auto-negotiation is still in progress. Since the result is not yet established, flow control is
disabled.
Case 2 - Auto-negotiation is enabled and unsuccessful (link partner not Auto-negotiation capable).
The link partner ability is undefined, effectively a don’t-care value, in this case. The duplex setting
will default to half-duplex in this case. Flow control is determined by the BP_EN_x bit.
Case 3 - Auto-negotiation is enabled and successful with half-duplex as a result. The link partner
ability is undefined since it only applies to full-duplex operation. Flow control is determined by the
BP_EN_x bit.
Cases 4-11 -Auto-negotiation is enabled and successful with full-duplex as the result. In these
cases, the advertisement registers and the link partner ability controls the RX and TX enables.
These cases match IEEE 802.3 Annex 28B.3.
Cases 4,5,6,8,10 - No flow control enabled
Case 7 - Asymmetric pause towards partner (away from switch port)
Case 9 - Symmetric pause
Case 11 - Asymmetric pause from partner (towards switch port)
6.3 10/100 Ethernet MACs
The Switch Fabric contains three 10/100 MAC blocks, one for each switch port (0,1,2). The 10/100
MAC provides the basic 10/100 Ethernet functionality, including transmission deferral and collision
back-off/retry, receive/transmit FCS checking and generation, receive/transmit pause flow control, and
transmit back pressure. The 10/100 MAC also includes RX and TX FIFOs and per port statistic
counters.
6.3.1 Receive MAC
The receive MAC (IEEE 802.3) sublayer decomposes Ethernet packets acquired via the internal MII
interface by stripping off the preamble sequence and Start of Frame Delimiter (SFD). The receive MAC
checks the FCS, the MAC Control Type, and the byte count against the drop conditions. The packet
is stored in the RX FIFO as it is received.
The receive MAC determines the validity of each received packet by checking the Type field, FCS, and
oversize or undersize conditions. All bad packets will be either immediately dropped or marked (at the
end) as bad packets.
Oversized packets are normally truncated at 1519 or 1523 (VLAN tagged) octets and marked as
erroneous. The MAC can be configured to accept packets up to 2048 octets (inclusive), in which case
the oversize packets are truncated at 2048 bytes and marked as erroneous.
Undersized packets are defined as packets with a length less than the minimum packet size. The
minimum packet size is defined to be 64 bytes, exclusive of preamble sequence and SFD.
The FCS and length/type fields of the frame are checked to detect if the packet has a valid MAC
control frame. When the MAC receives a MAC control frame with a valid FCS and determines the
operation code is a pause command (Flow Control frame), the MAC will load its internal pause counter
with the Number_of_Slots variable from the MAC control frame just received. Anytime the internal
pause counter is zero, the transmit MAC will be allowed to transmit (XON). If the internal pause counter
is not zero, the receive MAC will not allow the transmit MAC to transmit (XOFF). When the transmit
MAC detects an XOFF condition it will continue to transmit the current packet, terminating transmission
after the current packet has been transmitted until receiving the XON condition from the receive MAC.
The pause counter will begin to decrement at then end of the current transmission, or immediately if
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no transmission is underway. If another pause command is received while the transmitter is already in
pause, the new pause time indicated by the Flow Control packet will be loaded into the pause counter.
The pause function is enabled by either Auto-negotiation, or manually as discussed in Section 6.2.3,
"Flow Control Enable Logic," on page 70. Pause frames are consumed by the MAC and are not sent
to the Switch Engine. Non-pause control frames are optionally filtered or forwarded.
When the receive FIFO is full and additional data continues to be received, an overrun condition occurs
and the frame is discarded (FIFO space recovered) or marked as a bad frame.
The receive MAC can be disabled from receiving all frames by clearing the RX Enable bit of the Port
x MAC Receive Configuration Register (MAC_RX_CFG_x).
The size of the RX FIFO is 256 bytes. If a bad packet with less than 64 bytes is received, it will be
flushed from the FIFO automatically and the FIFO space recovered. Packets equal to or larger than
64 bytes with an error will be marked and reported to the Switch Engine. The Switch Engine will
subsequently drop the packet.
6.3.1.1 Receive Counters
The receive MAC gathers statistics on each packet and increments the related counter registers. The
following receive counters are supported for each Switch Fabric port. Refer to Table 13.14, “Indirectly
Accessible Switch Control and Status Registers,” on page 228 and Section 13.4.2.3 through
Section 13.4.2.22 for detailed descriptions of these counters.
Total undersized packets (Section 13.4.2.3, on page 245)
Total packets 64 bytes in size (Section 13.4.2.4, on page 246)
Total packets 65 through 127 bytes in size (Section 13.4.2.5, on page 247)
Total packets 128 through 255 bytes in size (Section 13.4.2.6, on page 248)
Total packets 256 through 511 bytes in size (Section 13.4.2.7, on page 249)
Total packets 512 through 1023 bytes in size (Section 13.4.2.8, on page 250)
Total packets 1024 through maximum bytes in size (Section 13.4.2.9, on page 251)
Total oversized packets (Section 13.4.2.10, on page 252)
Total OK packets (Section 13.4.2.11, on page 253)
Total packets with CRC errors (Section 13.4.2.12, on page 254)
Total multicast packets (Section 13.4.2.13, on page 255)
Total broadcast packets (Section 13.4.2.14, on page 256)
Total MAC Pause packets (Section 13.4.2.15, on page 257)
Total fragment packets (Section 13.4.2.16, on page 258)
Total jabber packets (Section 13.4.2.17, on page 259)
Total alignment errors (Section 13.4.2.18, on page 260)
Total bytes received from all packets (Section 13.4.2.19, on page 261)
Total bytes received from good packets (Section 13.4.2.20, on page 262)
Total packets with a symbol error (Section 13.4.2.21, on page 263)
Total MAC control packets (Section 13.4.2.22, on page 264)
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6.3.2 Transmit MAC
The transmit MAC generates an Ethernet MAC frame from TX FIFO data. This includes generating the
preamble and SFD, calculating and appending the frame checksum value, optionally padding
undersize packets to meet the minimum packet requirement size (64 bytes), and maintaining a
standard inter-frame gap time during transmit.
The transmit MAC can operate at 10/100Mbps, half- or full-duplex, and with or without flow control
depending on the state of the transmission. In half-duplex mode, the transmit MAC meets CSMA/CD
IEEE 802.3 requirements. The transmit MAC will re-transmit if collisions occur during the first 64 bytes
(normal collisions), or will discard the packet if collisions occur after the first 64 bytes (late collisions).
The transmit MAC follows the standard truncated binary exponential back-off algorithm, collision and
jamming procedures.
The transmit MAC pre-pends the standard preamble and SFD to every packet from the FIFO. The
transmit MAC also follows, as default, the standard Inter-Frame Gap (IFG). The default IFG is 96 bit
times and can be adjusted via the IFG Config field of the Port x MAC Transmit Configuration Register
(MAC_TX_CFG_x).
Packet padding and cyclic redundant code (FCS) calculation may be optionally performed by the
transmit MAC. The auto-padding process automatically adds enough zeros to packets shorter than 64
bytes. The auto-padding and FCS generation is controlled via the TX Pad Enable bit of the Port x MAC
Transmit Configuration Register (MAC_TX_CFG_x).
The transmit FIFO acts as a temporary buffer between the transmit MAC and the Switch Engine. The
FIFO logic manages the re-transmission for normal collision conditions or discards the frames for late
or excessive collisions.
When in full-duplex mode, the transmit MAC uses the flow-control algorithm specified in IEEE 802.3.
MAC pause frames are used primarily for flow control packets, which pass signalling information
between stations. MAC pause frames have a unique type of 8808h, and a pause op-code of 0001h.
The MAC pause frame contains the pause value in the data field. The flow control manager will auto-
adapt the procedure based on traffic volume and speed to avoid packet loss and unnecessary pause
periods.
When in half-duplex mode, the MAC uses a back pressure algorithm. The back pressure algorithm is
based on a forced collision and an aggressive back-off algorithm.
6.3.2.1 Transmit Counters
The transmit MAC gathers statistics on each packet and increments the related counter registers. The
following transmit counters are supported for each Switch Fabric port. Refer to Table 13.14, “Indirectly
Accessible Switch Control and Status Registers,” on page 228 and Section 13.4.2.25 through
Section 13.4.2.42 for detailed descriptions of these counters.
Total packets deferred (Section 13.4.2.25, on page 267)
Total pause packets (Section 13.4.2.26, on page 268)
Total OK packets (Section 13.4.2.27, on page 269)
Total packets 64 bytes in size (Section 13.4.2.28, on page 270)
Total packets 65 through 127 bytes in size (Section 13.4.2.29, on page 271)
Total packets 128 through 255 bytes in size (Section 13.4.2.30, on page 272)
Total packets 256 through 511 bytes in size (Section 13.4.2.31, on page 273)
Total packets 512 through 1023 bytes in size (Section 13.4.2.32, on page 274)
Total packets 1024 through maximum bytes in size (Section 13.4.2.33, on page 275)
Total undersized packets (Section 13.4.2.34, on page 276)
Total bytes transmitted from all packets (Section 13.4.2.35, on page 277)
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Total broadcast packets (Section 13.4.2.36, on page 278)
Total multicast packets (Section 13.4.2.37, on page 279)
Total packets with a late collision (Section 13.4.2.38, on page 280)
Total packets with excessive collisions (Section 13.4.2.39, on page 281)
Total packets with a single collision (Section 13.4.2.40, on page 282)
Total packets with multiple collisions (Section 13.4.2.41, on page 283)
Total collision count (Section 13.4.2.42, on page 284)
6.4 Switch Engine (SWE)
The Switch Engine (SWE) is a VLAN layer 2 (link layer) switching engine supporting 3 ports. The SWE
supports the following types of frame formats: untagged frames, VLAN tagged frames, and priority
tagged frames. The SWE supports both the 802.3 and Ethernet II frame formats.
The SWE provides the control for all forwarding/filtering rules. It handles the address learning and
aging, and the destination port resolution based upon the MAC address and VLAN of the packet. The
SWE implements the standard bridge port states for spanning tree and provides packet metering for
input rate control. It also implements port mirroring, broadcast throttling, and multicast pruning and
filtering. Packet priorities are supported based on the IPv4 TOS bits and IPv6 Traffic Class bits using
a DIFFSERV Table mapping, the non-DIFFSERV mapped IPv4 precedence bits, VLAN priority using
a per port Priority Regeneration Table, DA based static priority, and Traffic Class mapping to one of 4
QoS transmit priority queues.
The following sections detail the various features of the Switch Engine.
6.4.1 MAC Address Lookup Table
The Address Logic Resolution (ALR) maintains a 512 entry MAC Address Table. The ALR searches
the table for the destination MAC address. If the search finds a match, the associated data is returned
indicating the destination port or ports, whether to filter the packet, the packet’s priority (used if
enabled), and whether to override the ingress and egress spanning tree port state. Figure 6.3 displays
the ALR table entry structure. Refer to the Switch Engine ALR Write Data 0 Register
(SWE_ALR_WR_DAT_0) and Switch Engine ALR Write Data 1 Register (SWE_ALR_WR_DAT_1) for
detailed descriptions of these bits.
Figure 6.3 ALR Table Entry Structure
57
Age /
Override
Valid
58
Static
56
Filter
55
Priority Port
50 49 48
MAC Address
47 0
...
Bit 53 52 5154
Priority
Enable
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6.4.1.1 Learning/Aging/Migration
The ALR adds new MAC addresses upon ingress along with the associated receive port.
If the source MAC address already exists, the entry is refreshed. This action serves two purposes.
First, if the source port has changed due to a network reconfiguration (migration), it is updated.
Second, each instance the entry is refreshed, the aging status bit is set, keeping the entry active.
Learning can be disabled per port via the Enable Learning on Ingress field of the Switch Engine Port
Ingress Configuration Register (SWE_PORT_INGRSS_CFG).
During each aging period, the ALR scans the learned MAC addresses. For entries which have the
aging status bit set, the ALR simply clears the bit. As mentioned above, if a MAC address is
subsequently refreshed, the aging bit will be set again and the process would repeat. If a learned entry
already had its aging status bit cleared (by a previous scan), the ALR will instead remove the learned
entry. Therefore, if two scans occur before a MAC address is refreshed, the entry will be aged and
removed. Each aging period is approximately 5 minutes. Therefore an entry will be aged and removed
at a minimum of 5 minutes, and a maximum of 10 minutes.
6.4.1.2 Static Entries
If a MAC address entry is manually added by the host CPU, it can be (and typically is) marked as
static. Static entries are not subjected to the aging process. Static entries also cannot be changed by
the learning process (including migration).
6.4.1.3 Multicast Pruning
The destination port that is returned as a result of a destination MAC address lookup may be a single
port or any combination of ports. The latter is used to setup multicast address groups. An entry with
a multicast MAC address would be entered manually by the host CPU with the appropriate destination
port(s). Typically, the Static bit should also be set to prevent automatic aging of the entry.
6.4.1.4 Address Filtering
Filtering can be performed on a destination MAC address. Such an entry would be entered manually
by the host CPU with the Filter bit active. Typically, the Static bit should also be set to prevent
automatic aging of the entry.
6.4.1.5 Spanning Tree Port State Override
A special spanning tree port state override setting can be applied to MAC address entries. When the
host CPU manually adds an entry with both the Static and Age bits set, packets with a matching
destination address will bypass the spanning tree port state (except the Disabled state) and will be
forwarded. This feature is typically used to allow the reception of the BPDU packets while a port is in
the non-forwarding state. Refer to Section 6.4.5, "Spanning Tree Support," on page 82 for additional
details.
6.4.1.6 MAC Destination Address Lookup Priority
If enabled globally in the Switch Engine Global Ingress Configuration Register
(SWE_GLOBAL_INGRSS_CFG) and per entry with the Priority Enable bit, the transmit priority for MAC
address entries is taken from the associated data of that entry.
6.4.1.7 Host Access
The ALR contains a learning engine that is used by the host CPU to add, delete, and modify the MAC
Address Table. This engine is accessed by using the Switch Engine ALR Command Register
(SWE_ALR_CMD), Switch Engine ALR Command Status Register (SWE_ALR_CMD_STS), Switch
Engine ALR Write Data 0 Register (SWE_ALR_WR_DAT_0), and Switch Engine ALR Write Data 1
Register (SWE_ALR_WR_DAT_1).
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The following procedure should be followed in order to add, delete, and modify the ALR entries:
1. Write the Switch Engine ALR Write Data 0 Register (SWE_ALR_WR_DAT_0) and Switch Engine
ALR Write Data 1 Register (SWE_ALR_WR_DAT_1) with the desired MAC address and control
bits.
Note: An entry can be deleted by setting the Valid bit to 0.
2. Write the Switch Engine ALR Command Register (SWE_ALR_CMD) register with 0004h (Make
Entry).
3. Poll the Make Pending bit in the Switch Engine ALR Command Status Register
(SWE_ALR_CMD_STS) until it is cleared.
4. Write the Switch Engine ALR Command Register (SWE_ALR_CMD) with 0000h.
The ALR contains a search engine that is used by the host to read the MAC Address Table. This
engine is accessed by using the Switch Engine ALR Command Register (SWE_ALR_CMD), Switch
Engine ALR Read Data 0 Register (SWE_ALR_RD_DAT_0), and Switch Engine ALR Read Data 1
Register (SWE_ALR_RD_DAT_1).
Note: The entries read are not necessarily in the same order as they were learned or manually
added.
The following procedure should be followed in order to read the ALR entries:
1. Write the Switch Engine ALR Command Register (SWE_ALR_CMD) with 0002h (Get First Entry).
2. Write the Switch Engine ALR Command Register (SWE_ALR_CMD) with 0000h (Clear the Get
First Entry Bit).
3. Poll the Valid and End of Table bits in the Switch Engine ALR Read Data 1 Register
(SWE_ALR_RD_DAT_1) until either is set.
4. If the Valid bit is set, then the entry is valid and the data from the Switch Engine ALR Read Data
0 Register (SWE_ALR_RD_DAT_0) and Switch Engine ALR Read Data 1 Register
(SWE_ALR_RD_DAT_1) can be stored.
5. If the End of Table bit is set, then exit.
6. Write the Switch Engine ALR Command Register (SWE_ALR_CMD) with 0001h (Get Next Entry).
7. Write the Switch Engine ALR Command Register (SWE_ALR_CMD) with 0000h (Clear the Get
Next Entry bit).
8. Go to step 3.
Note: Refer to Section 13.4.3.1, on page 287 through Section 13.4.3.6, on page 294 for detailed
definitions of these registers.
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6.4.2 Forwarding Rules
Upon ingress, packets are filtered or forwarded based on the following rules:
If the destination port equals the source port (local traffic), the packet is filtered.
If the source port is in the Disabled state, the packet is filtered.
If the source port is in the Learning or Listening / Blocking state, the packet is filtered (unless the
Spanning Tree Port State Override is in effect).
If the packet is a multicast packet and it is identified as a IGMP packet and IGMP monitoring is
enabled (respectively), the packet is redirected to the IGMP monitor port(s). This check is not done
on special tagged packets from the host CPU port when an ALR lookup is not requested. Refer to
Section 6.4.10.1, "Packets from the Host CPU," on page 88 for additional information.
If the destination port is in the disabled state, the packet is filtered. (This rule is for a destination
MAC address which is found in the ALR table and the ALR result indicates a single destination
port. When there are multiple destination ports or when the MAC address is not found, the packet
is sent to only those ports that are in the Forwarding state.)
If the destination port is in the Learning or Listening / Blocking state, the packet is filtered (unless
the Spanning Tree Port State Override is in effect). (This rule is for a destination MAC address
which is found in the ALR table and the ALR result indicates a single destination port. When there
are multiple destination ports or when the MAC address is not found, the packet is sent to only
those ports that are in the Forwarding state.)
If the Filter bit for the Destination Address is set in the ALR table, the packet is filtered.
If the packet has a unicast destination MAC address which is not found in the ALR table and the
Drop Unknown bit is set, the packet is filtered.
If the packet has a multicast destination MAC address which is not found in the ALR table and the
Filter Multicast bit is set, the packet is filtered.
If the packet has a broadcast destination MAC address and the Broadcast Storm Control level has
been reached, the packet is discarded.
If Drop on Yellow is set, the packet is colored Yellow, and randomly selected, it is discarded.
If Drop on Red is set and the packet is colored Red, it is discarded.
If the destination address was not found in the ALR table (an unknown or a broadcast) and the
Broadcast Buffer Level is exceeded, the packet is discarded.
If there is insufficient buffer space, the packet is discarded.
If the destination address was not found in the ALR table (an unknown or a broadcast) or the
destination address was found in the ALR table with the ALR result indicating multiple destination
ports and the port forward states resulted in zero valid destination ports, the packet is filtered.
When the switch is enabled for VLAN support, these following rules also apply:
If the packet is untagged or priority tagged and the Admit Only VLAN bit for the ingress port is set,
the packet is filtered.
If the packet is tagged and has a VID equal to FFFh, it is filtered.
If Enable Membership Checking on Ingress is set, Admit Non Member is cleared, and the source
port is not a member of the incoming VLAN, the packet is filtered.
If Enable Membership Checking on Ingress is set and the destination port is not a member of the
incoming VLAN, the packet is filtered. (This rule is for a destination MAC address which is found
in the ALR table and the ALR result indicates a single destination port. When there are multiple
destination ports or when the MAC address is not found, the packet is sent to only those ports that
are in the Forwarding state.)
If the destination address was not found in the ALR table (as unknown or broadcast) or the
destination address was found in the ALR table with the ALR result indicating multiple destination
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ports and the VLAN broadcast domain containment resulted in zero valid destination ports, the
packet is filtered.
Note: For the last three cases, if the VID is not in the VLAN table, the VLAN is considered foreign
and the membership result is NULL. A NULL membership will result in the packet being filtered
if Enable Membership Checking is set. A NULL membership will also result in the packet being
filtered if the destination address is not found in the ALR table (since the packet would have
no destinations).
6.4.3 Transmit Priority Queue Selection
The transmit priority queue may be selected from five options. As shown in Figure 6.4, the priority may
be based on:
the static value for the destination address in the ALR table
the precedence bits in the IPv4 TOS octet
the DIFFSERV mapping table indexed by the IPv4 TOS octet or the IPv6 Traffic Class octet
the VLAN tag priority field using the per port Priority Regeneration table
the port default
All options are sent through the Traffic Class table which maps the selected priority to one of the four
output queues.
Figure 6.4 Switch Engine Transmit Queue Selection
priority
calculation
programmable
DiffServ table
programmable
port default
table
programmable
Priority
Regeneration
table
per port
3b
3b
3b
2b
6b 3b
3b
static DA
override
Packet is Tagged
VL Higher Priority
Packet is IPv4
Packet is IP
Use Precedence
Use IP
ALR Priority Enable Bit
IPv4(TOS)
IPv6(TC)
DA Highest Priority
priority queue
Source Port
ALR Priority
VLAN Priority
IPv4 Precedence
2b
3b
Use Tag
Packet is from Host
programmable
Traffic Class
table
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The transmit queue priority is based on the packet type and device configuration as shown in
Figure 6.5. Refer to Section 13.4.3.16, "Switch Engine Global Ingress Configuration Register
(SWE_GLOBAL_INGRSS_CFG)," on page 306 for definitions of the configuration bits.
Figure 6.5 Switch Engine Transmit Queue Calculation
DA Highest
Priority
ALR Priority
Enable Bit
Y
Y
Resolved Priority =
Priority Regen[VLAN
Priority]
N
Packet is IPv4/v6
& Use IP
Resolved Priority =
IP Precedence
Y
Use Precedence
Y N
Resolved Priority =
DIFFSERV[TC]
N
N
Y
Use Tag &
Packet is
Tagged
Y
N
N
Resolved Priority =
Default Priority[Source
Port]
wait for ALR result
Queue =
Traffic Class[Resolved Priority]
Packet is IPv4
Resolved Priority =
DIFFSERV[TOS]
Y
N
Get Queue Done
VL Higher
Priority
Use Tag &
Packet is
Tagged
N
Y
Get Queue
Packet fr om Host
N
Y
Resolved Priority =
ALR Priority
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6.4.3.1 Port Default Priority
As detailed in Figure 6.5, the default priority is based on the ingress port’s priority bits in its port VID
value. The PVID table is read and written by using the Switch Engine VLAN Command Register
(SWE_VLAN_CMD), Switch Engine VLAN Write Data Register (SWE_VLAN_WR_DATA), Switch
Engine VLAN Read Data Register (SWE_VLAN_RD_DATA), and Switch Engine VLAN Command
Status Register (SWE_VLAN_CMD_STS). Refer to Section 13.4.3.8, on page 296 through Section
13.4.3.11, on page 301 for detailed VLAN register descriptions.
6.4.3.2 IP Precedence Based Priority
The transmit priority queue can be chosen based on the Precedence bits of the IPv4 TOS octet. This
is supported for tagged and non-tagged packets for both type field and length field encapsulations. The
Precedence bits are the three most significant bits of the IPv4 TOS octet.
6.4.3.3 DIFFSERV Based Priority
The transmit priority queue can be chosen based on the DIFFSERV usage of the IPv4 TOS or IPv6
Traffic Class octet. This is supported for tagged and non-tagged packets for both type field and length
field encapsulations.
The DIFFSERV table is used to determine the packet priority from the 6-bit Differentiated Services (DS)
field. The DS field is defined as the six most significant bits of the IPv4 TOS octet or the IPv6 Traffic
Class octet and is used as an index into the DIFFSERV table. The output of the DIFFSERV table is
then used as the priority. This priority is then passed through the Traffic Class table to select the
transmit priority queue.
Note: The DIFFSERV table is not initialized upon reset or power-up. If DIFFSERV is enabled, then
the full table must be initialized by the host.
The DIFFSERV table is read and written by using the Switch Engine DIFFSERV Table Command
Register (SWE_DIFFSERV_TBL_CFG), Switch Engine DIFFSERV Table Write Data Register
(SWE_DIFFSERV_TBL_WR_DATA), Switch Engine DIFFSERV Table Read Data Register
(SWE_DIFFSERV_TBL_RD_DATA), and Switch Engine DIFFSERV Table Command Status Register
(SWE_DIFFSERV_TBL_CMD_STS). Refer to Section 13.4.3.12, on page 302 through Section
13.4.3.15, on page 305 for detailed DIFFSERV register descriptions.
6.4.3.4 VLAN Priority
As detailed in Figure 6.5, the transmit priority queue can be taken from the priority field of the VLAN
tag. The VLAN priority is sent through a per port Priority Regeneration table, which is used to map the
VLAN priority into a user defined priority.
The Priority Regeneration table is programmed by using the Switch Engine Port 0 Ingress VLAN
Priority Regeneration Table Register (SWE_INGRSS_REGEN_TBL_0), Switch Engine Port 1 Ingress
VLAN Priority Regeneration Table Register (SWE_INGRSS_REGEN_TBL_1), and Switch Engine Port
2 Ingress VLAN Priority Regeneration Table Register (SWE_INGRSS_REGEN_TBL_2). Refer to
Section 13.4.3.33, on page 325 through Section 13.4.3.35, on page 327 for detailed descriptions of
these registers.
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6.4.4 VLAN Support
The Switch Engine supports 16 active VLANs out of a possible 4096. The VLAN table contains the 16
active VLAN entries, each consisting of the VID, the port membership, and un-tagging instructions.
On ingress, if a packet has a VLAN tag containing a valid VID (not 000h or FFFh), the VID table is
searched. If the VID is found, the VLAN is considered active and the membership and un-tag
instruction is used. If the VID is not found, the VLAN is considered foreign and the membership result
is NULL. A NULL membership will result in the packet being filtered if Enable Membership Checking
is set. A NULL membership will also result in the packet being filtered if the destination address is not
found in the ALR table (since the packet would have no destinations).
On ingress, if a packet does not have a VLAN tag or if the VLAN tag contains VID with a value of 0
(priority tag), the packet is assigned a VLAN based on the Port Default VID (PVID) and Priority. The
PVID is then used to access the above VLAN table. The usage of the PVID can be forced by setting
the 802.1Q VLAN Disable bit, in effect creating port based VLANs.
The VLAN membership of the packet is used for ingress and egress checking and for VLAN broadcast
domain containment. The un-tag instructions are used at egress on ports defined as hybrid ports.
Refer to Section 13.4.3.8, on page 296 through Section 13.4.3.11, on page 301 for detailed VLAN
register descriptions.
6.4.5 Spanning Tree Support
Hardware support for the Spanning Tree Protocol (STP) and the Rapid Spanning Tree Protocol (RSTP)
includes a per port state register as well as the override bit in the MAC Address Table entries (Section
6.4.1.5, on page 76) and the host CPU port special tagging (Section 6.4.10, on page 88).
The Switch Engine Port State Register (SWE_PORT_STATE) is used to place a port into one of the
modes as shown in Ta b l e 6 . 2 . Normally only Port 1 and Port 2 are placed into modes other than
forwarding. Port 0, which is connected to the host CPU, should normally be left in forwarding mode.
Figure 6.6 VLAN Table Entry Structure
Table 6.2 Spanning Tree States
Port State Hardware Action Software Action
11 - Disabled Received packets on the port are
always discarded.
Transmissions to the port are always
blocked.
Learning on the port is disabled.
The host CPU may attempt to send packets to the
port in this state, but they will not be transmitted.
17 16 15 14 13 12
VID
11 0
...
Un-tag
MII
Member
MII
Un-tag
Port 1
Member
Port 1
Un-tag
Port 2
Member
Port 2
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6.4.6 Ingress Flow Metering and Coloring
Hardware ingress rate limiting is supported by metering packet streams and marking packets as either
Green, Yellow, or Red according to three traffic parameters: Committed Information Rate (CIR),
Committed Burst Size (CBS), and Excess Burst Size (EBS). A packet is marked Green if it does not
exceed the CBS, Yellow if it exceeds to CBS but not the EBS, or Red otherwise.
Ingress flow metering and coloring is enabled via the Ingress Rate Enable bit in the Switch Engine
Ingress Rate Configuration Register (SWE_INGRSS_RATE_CFG). Once enabled, each incoming
packet is classified into a stream. Streams are defined as per port (3 streams), per priority (8 streams),
or per port & priority (24 streams) as selected via the Rate Mode bits in the Switch Engine Ingress
Rate Configuration Register (SWE_INGRSS_RATE_CFG). Each stream can have a different CIR
setting. All streams share common CBS and EBS settings. CIR, CBS, and EBS are programmed via
the Switch Engine Ingress Rate Command Register (SWE_INGRSS_RATE_CMD) and Switch Engine
Ingress Rate Write Data Register (SWE_INGRSS_RATE_WR_DATA).
Each stream is metered according to RFC 2697. At the rate set by the CIR, two token buckets are
credited per stream. First, the Committed Burst bucket is incremented up to the maximum set by the
CBS. Once the Committed Burst bucket is full, the Excess Burst bucket is incremented up to the
01 - Blocking Received packets on the port are
discarded unless overridden.
Transmissions to the port are blocked
unless overridden.
Learning on the port is disabled.
The MAC Address Table should be programmed
with entries that the host CPU needs to receive
(e.g. the BPDU address). The static and override
bits should be set.
The host CPU may send packets to the port in this
state. Only packets with STP override will be
transmitted.
Note: There is no hardware distinction between
the Blocking and Listening states.
01 - Listening Received packets on the port are
discarded unless overridden.
Transmissions to the port are blocked
unless overridden.
Learning on the port is disabled.
The MAC Address Table should be programmed
with entries that the host CPU needs to receive
(e.g. the BPDU address). The static and override
bits should be set.
The host CPU may send packets to the port in this
state. Only packets with STP override will be
transmitted.
10 - Learning Received packets on the port are
discarded unless overridden.
Transmissions to the port are blocked
unless overridden.
Learning on the port is enabled.
The MAC Address Table should be programmed
with entries that the host CPU needs to receive
(e.g. the BPDU address). The static and override
bits should be set.
The host CPU may send packets to the port in this
state. Only packets with STP override will be
transmitted.
00 - Forwarding Received packets on the port are
forwarded normally.
Transmissions to the port are sent
normally.
Learning on the port is enabled.
The MAC Address Table should be programmed
with entries that the host CPU needs to receive
(e.g. the BPDU address). The static and override
bits should be set.
The host CPU may send packets to the port in this
state.
Table 6.2 Spanning Tree States (continued)
Port State Hardware Action Software Action
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maximum set by the EBS. The CIR rate is specified in time per byte. The value programmed is in
approximately 20 nS per byte increments. Typical values are listed in Tab l e 6.3 . When a port is
receiving at 10Mbps, any setting faster than 39 has the effect of not limiting the rate.
After each packet is received, the bucket is decremented. If the Committed Burst bucket has sufficient
tokens, it is debited and the packet is colored Green. If the Committed Burst bucket lacks sufficient
tokens for the packet, the Excess Burst bucket is checked. If the Excess Burst bucket has sufficient
tokens, it is debited, the packet is colored Yellow and is subjected to random discard. If the Excess
Burst bucket lacks sufficient tokens for the packet, the packet is colored Red and is discarded.
Note: All of the token buckets are initialized to the default value of 1536. If lower values are
programmed into the CBS and EBS parameters, the token buckets will need to be normally
depleted below these values before the values have any affect on limiting the maximum value
of the token buckets.
Refer to Section 13.4.3.25, on page 316 through Section 13.4.3.29, on page 321 for detailed register
descriptions.
Table 6.3 Typical Ingress Rate Settings
CIR Setting Time Per Byte Bandwidth
0-3 80 nS 100 Mbps
4 100 nS 80 Mbps
5 120 nS 67 Mbps
6 140 nS 57 Mbps
7 160 nS 50 Mbps
9 200 nS 40 Mbps
12 260 nS 31 Mbps
19 400 nS 20 Mbps
39 800 nS 10 Mbps
79 1600 nS 5 Mbps
160 3220 nS 2.5 Mbps
402 8060 nS 1 Mbps
804 16100 nS 500 Kbps
1610 32220 nS 250 Kbps
4028 80580 nS 100 Kbps
8056 161140 nS 50 Kbps
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6.4.6.1 Ingress Flow Calculation
Based on the flow monitoring mode, an ingress flow definition can include the ingress priority. This is
calculated similarly to the transmit queue with the exception that the Traffic Class table is not used. As
shown in Figure 6.7, the priority can be based on:
The static value for the destination address in the ALR table.
The precedence bits in the IPv4 TOS octet
The DIFFSERV mapping table indexed by the IPv4 TOS octet or the IPv6 Traffic Class octet
The VLAN tag priority field using the per port Priority Regeneration table
The port default
Figure 6.7 Switch Engine Ingress Flow Priority Selection
Programmable
DIFFSERV Table
Programmable
Port Default
Table
3b
2b
6b 3b
Packet is Tagged
VL Higher Priority
Packet is IPv4
Packet is IP
Use Precedence
Use IP
IPv4( TOS)
IPv6(TC)
Source Port
VLAN Priority
IPv4 Precedence 3b
Use Tag
Priority
Calculation
Packet is from Host
flow priority
3b
3b
Static DA
Override
Programmable
Priority
Regeneration
Table per Port
ALR Priority
DA Highest Priority
ALR Priority Enable Bit
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The ingress flow calculation is based on the packet type and the device configuration as shown in
Figure 6.8.
Figure 6.8 Switch Engine Ingress Flow Priority Calculation
DA Highest
Priority
ALR Priority
Enable Bit
Y
Y
Flow Priority =
Priority Regen[VLAN
Priority]
N
Packet is IPv4/v6
& Use IP
Flow Priority =
IP Precedence
Y
Use Precedence
Y N
Flow Priority =
DIFFSERV[TC]
N
N
Y
Use Tag &
Packet is
Tagged
Y
N
N
Flow Priority =
Default Priority[Source
Port]
wait for ALR result
Packet is IPv4
Flow Priority =
DIFFSERV[TOS]
Y
N
Get Flow Priority Done
VL Higher
Priority
Use Tag &
Packet is
Tagged
N
Y
Get Flow Priority
Packet
from Host & queue
calc ulation not
requested
N
Y
Flow Priority =
ALR Priority
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6.4.7 Broadcast Storm Control
In addition to ingress rate limiting, the device supports hardware broadcast storm control on a per port
basis. This feature is enabled via the Switch Engine Broadcast Throttling Register
(SWE_BCST_THROT). The allowed rate per port is specified as the number of bytes multiplied by 64
allowed to be received every 1.72 mS interval. Packets that exceed this limit are dropped. Typical
values are listed in Ta b le 6.4. When a port is receiving at 10Mbps, any setting above 34 has the effect
of not limiting the rate.
In addition to the rate limit, the Buffer Manager Broadcast Buffer Level Register (BM_BCST_LVL)
specifies the maximum number of buffers that can be used by broadcasts, multicasts, and unknown
unicasts.
6.4.8 IPv4 IGMP Support
The device provides Internet Group Management Protocol (IGMP) hardware support using two
mechanisms: IGMP monitoring and Multicast Pruning.
On ingress, if IGMP packet monitoring is enabled in the Switch Engine Global Ingress Configuration
Register (SWE_GLOBAL_INGRSS_CFG), IGMP multicast packets are trapped and redirected to the
IGMP monitor port (typically set to the port to which the host CPU is connected). IGMP packets are
identified as IPv4 packets with a protocol of 2. Both Ethernet and IEEE 802.3 frame formats are
supported as are VLAN tagged packets.
Once the IGMP packets are received by the host CPU, the host software can decide which port or
ports need to be members of the multicast group. This group is then added to the ALR table as detailed
in Section 6.4.1.3, "Multicast Pruning," on page 76. The host software should also forward the original
IGMP packet if necessary.
Normally, packets are never transmitted back to the receiving port. For IGMP monitoring, this may
optionally be enabled via the Switch Engine Global Ingress Configuration Register
(SWE_GLOBAL_INGRSS_CFG). This function would be used if the monitoring port wished to
participate in the IGMP group without the need to perform special handling in the transmit portion of
the driver software.
Table 6.4 Typical Broadcast Rate Settings
Broadcast Throttle Level Bandwidth
252 75 Mbps
168 50 Mbps
134 40 Mbps
67 20 Mbps
34 10 Mbps
17 5 Mbps
82.4 Mbps
41.2 Mbps
3 900 Kbps
2 600 Kbps
1 300 Kbps
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Note: Most forwarding rules are skipped when a packet is monitored. However, a packet is still filtered
if:
The source port is in the Disabled state
The source port is in the Learning or Listening / Blocking state (unless Spanning Tree Port
State Override is in effect.
VLAN’s are enabled, the packet is untagged or priority tagged, and the Admit Only VLAN
bit for the ingress port is set.
VLAN’s are enabled and the packet is tagged and had a VID equal to FFFh.
VLAN’s are enabled, Enabled Membership Checking on Ingress is set, Admit Non Member
is cleared, and the source port is not a member of the incoming VLAN.
6.4.9 Port Mirroring
The device supports port mirroring where packets received or transmitted on a port or ports can also
be copied onto another “sniffer” port.
Port mirroring is configured using the Switch Engine Port Mirroring Register (SWE_PORT_MIRROR).
Multiple mirrored ports can be defined, but only one sniffer port can be defined.
When receive mirroring is enabled, packets that are forwarded from a port designated as a mirrored
port are also transmitted by the sniffer port. For example, Port 2 is setup to be a mirrored port and
Port 0 is setup to be the sniffer port. If a packet is received on Port 2 with a destination of Port 1, it
is forwarded to both Port 1 and Port 0.
When transmit mirroring is enabled, packets that are forwarded to a port designated as a mirrored port
are also transmitted by the sniffer port. For example, Port 2 is setup to be a mirrored port and Port 0
is setup to be the sniffer port. If a packet is received on Port 1 with a destination of Port 2, it is
forwarded to both Port 2 and Port 0.
Note: A packet will never be transmitted out of the receiving port. A receive packet is not normally
mirrored if it is filtered. This can optionally be enabled.
6.4.10 Host CPU Port Special Tagging
The Switch Engine Ingress Port Type Register (SWE_INGRSS_PORT_TYP) and Buffer Manager
Egress Port Type Register (BM_EGRSS_PORT_TYPE) are used to enable a special VLAN tag that is
used by the host CPU. This special tag is used to specify the port(s) where packets from the CPU
should be sent, and to indicate which port received the packet that was forwarded to the CPU.
6.4.10.1 Packets from the Host CPU
The Switch Engine Ingress Port Type Register (SWE_INGRSS_PORT_TYP) configures the switch to
use the special VLAN tag in packets from the host CPU as a destination port indicator. A setting of
11b should be used on the port that is connected to the host CPU (typically Port 0). A setting of 00b
should be used on the normal network ports.
The special VLAN tag is a normal VLAN tag where the VID field is used as the destination port
indicator.
VID bit 3 indicates a request for an ALR lookup.
If VID bit 3 is zero, then bits 0 and 1 specify the destination port (0, 1, 2) or broadcast (3). Bit 4 is
used to specify if the STP port state should be overridden. When set, the packet will be transmitted,
even if the destination port(s) is (are) in the Learning or Listening / Blocking state.
If VID bit 3 is one, then the normal ALR lookup is performed and learning is performed on the source
address (if enabled in the Switch Engine Port Ingress Configuration Register
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(SWE_PORT_INGRSS_CFG) and the port state for the CPU port is set to Forwarding or Learning).
The STP port state override is taken from the ALR entry.
VID bit 5 indicates a request to calculate the packet priority (and egress queue) based on the packet
contents.
If VID bit 5 is zero, the PRI field from the VLAN tag is used as the packet priority.
If VID bit 5 is one, the packet priority is calculated from the packet contents. The procedure described
in Section 6.4.3, "Transmit Priority Queue Selection," on page 79 is followed with the exception that
the special tag is skipped and the VLAN priority is taken from the second VLAN tag, if it exists.
VID bit 6 indicates a request to follow VLAN rules.
If VID bit 6 is zero, a default membership of “all ports” is assumed and no VLAN rules are followed.
If VID bit 6 is one, all ingress and egress VLAN rules are followed. The procedure described in Section
6.4.2, "Forwarding Rules," on page 78 is followed with the exception that the special tag is skipped
and the VID is taken from the second VLAN tag if it exists.
Upon egress from the destination port(s), the special tag is removed. If a regular VLAN tag needs to
be sent as part of the packet, then it should be part of the packet data from the host CPU port or set
as an unused bit in the VID field.
Note: When specifying Port 0 as the destination port, the VID will be set to 0. A VID of 0 is normally
considered a priority tagged packet. Such a packet will be filtered if Admit Only VLAN is set
on the host CPU port. Either avoid setting Admit Only VLAN on the host CPU port or set an
unused bit in the VID field.
Note: The maximum size tagged packet that can normally be sent into a switch port (on port 0) is
1522 bytes. Since the special tag consumes four bytes of the packet length, the outgoing
packet is limited to 1518 bytes, even if it contains a regular VLAN tag as part of the packet
data. If a larger outgoing packet is required, the Jumbo2K bit in the Port x MAC Receive
Configuration Register (MAC_RX_CFG_x) of Port 0 should be set.
6.4.10.2 Packets to the Host CPU
The Buffer Manager Egress Port Type Register (BM_EGRSS_PORT_TYPE) configures the switch to
add the special VLAN tag in packets to the host CPU as a source port indicator. A setting of 11b should
be used only on the port that is connected to the host CPU (typically Port 0). Other settings can be
used on the normal network ports as needed.
The special VLAN tag is a normal VLAN tag where:
The priority field indicates the packet’s priority as classified on receive.
Bits 0 and 1 of the VID field specify the source port (0, 1, or 2).
Bit 3 of the VID field indicates the packet was a monitored IGMP packet.
Bit 4 of the VID field indicates STP override was set (static AND age bits set) in the ALR entry for
the packet’s Destination MAC Address.
Bit 5 of the VID field indicates the static bit was set in the ALR entry for the packet’s Destination
MAC address.
Bit 6 of the VID field indicates priority enable was set in the ALR entry or the packet’s Destination
MAC address.
Bits 7,8, and 9 of the VID field are the priority field in the ALR entry for the packet’s Destination
MAC address - these can be used as a tag to identify different packet types (PTP, RSTP, etc.) when
the host CPU adds MAC address entries.
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Note: Bits 4 through 9 of the VID field will be all zero for Destination MAC Addresses that have been
learned (i.e., not added by the host) or are not found in the ALR table (i.e., not learned or
added by the host).
Upon egress from the host CPU port, the special tag is added. If a regular VLAN tag already exists,
it is not deleted. Instead it will follow the special tag.
6.4.11 Counters
A counter is maintained per port that contains the number of MAC address that were not learned or
were overwritten by a different address due to MAC Address Table space limitations. These counters
are accessible via the following registers:
Switch Engine Port 0 Learn Discard Count Register (SWE_LRN_DISCRD_CNT_0)
Switch Engine Port 1 Learn Discard Count Register (SWE_LRN_DISCRD_CNT_1)
Switch Engine Port 2 Learn Discard Count Register (SWE_LRN_DISCRD_CNT_2)
A counter is maintained per port that contains the number of packets filtered at ingress. This count
includes packets filtered due to broadcast throttling, but does not include packets dropped due to
ingress rate limiting. These counters are accessible via the following registers:
Switch Engine Port 0 Ingress Filtered Count Register (SWE_FILTERED_CNT_0)
Switch Engine Port 1 Ingress Filtered Count Register (SWE_FILTERED_CNT_1)
Switch Engine Port 2 Ingress Filtered Count Register (SWE_FILTERED_CNT_2)
6.5 Buffer Manager (BM)
The Buffer Manager (BM) provides control of the free buffer space, the multiple priority transmit
queues, transmission scheduling, and packet dropping. VLAN tag insertion and removal is also
performed by the Buffer Manager. The following sections detail the various features of the Buffer
Manager.
6.5.1 Packet Buffer Allocation
The packet buffer consists of 32KB of RAM that is dynamically allocated in 128 byte blocks as packets
are received. Up to 16 blocks may be used per packet, depending on the packet length. The blocks
are linked together as the packet is received. If a packet is filtered, dropped, or contains a receive
error, the buffers are reclaimed.
6.5.1.1 Buffer Limits and Flow Control Levels
The BM keeps track of the amount of buffers used per each ingress port. These counts are used to
generate flow control (half-duplex backpressure or full-duplex pause frames) and to limit the amount
of buffer space that can be used by any individual receiver (hard drop limit). The flow control and drop
limit thresholds are dynamic and adapt based on the current buffer usage. Based on the number of
active receiving ports, the drop level and flow control pause and resume thresholds adjust between
fixed settings and two user programmable levels via the Buffer Manager Drop Level Register
(BM_DROP_LVL), Buffer Manager Flow Control Pause Level Register (BM_FC_PAUSE_LVL), and
Buffer Manager Flow Control Resume Level Register (BM_FC_RESUME_LVL) respectively.
The BM also keeps a count of the number of buffers that are queued for multiple ports (broadcast
queue). This count is compared against the Buffer Manager Broadcast Buffer Level Register
(BM_BCST_LVL), and if the configured drop level is reached or exceeded, subsequent packets are
dropped.
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6.5.2 Random Early Discard (RED)
Based on the ingress flow monitoring detailed in Section 6.4.6, "Ingress Flow Metering and Coloring,"
on page 83, packets are colored as Green, Yellow, or Red. Packets colored Red are always discarded
if the Drop on Red bit in the Buffer Manager Configuration Register (BM_CFG) is set. If the Drop on
Yel low bit in the Buffer Manager Configuration Register (BM_CFG) is set, packets colored Yellow are
randomly discarded based on the moving average number of buffers used by the ingress port.
The probability of a discard is programmable into the Random Discard Weight table via the Buffer
Manager Random Discard Table Command Register (BM_RNDM_DSCRD_TBL_CMD), Buffer
Manager Random Discard Table Write Data Register (BM_RNDM_DSCRD_TBL_WDATA), and Buffer
Manager Random Discard Table Read Data Register (BM_RNDM_DSCRD_TBL_RDATA). The
Random Discard Weight table contains sixteen entries, each 10-bits wide. Each entry corresponds to
a range of the average number of buffers used by the ingress port. Entry 0 is for 0 to 15 buffers, entry
1 is for 16 to 31 buffers, etc. The probability for each entry us set in 1/1024’s. For example, a setting
of 1 is 1-in-1024, or approximately 0.1%. A setting of all ones (1023) is 1023-in-1024, or approximately
99.9%.
Refer to Section 13.4.4.10, "Buffer Manager Random Discard Table Command Register
(BM_RNDM_DSCRD_TBL_CMD)," on page 343 for additional details on writing and reading the
Random Discard Weight table.
6.5.3 Transmit Queues
Once a packet has been completely received, it is queued for transmit. There are four queues per
transmit port, one for each level of transmit priority. Each queue is virtual (if there are no packets for
that port/priority, the queue is empty), and dynamic (a queue may be any length if there is enough
memory space). When a packet is read from the memory and sent out to the corresponding port, the
used buffers are released.
6.5.4 Transmit Priority Queue Servicing
When a transmit queue is non-empty, it is serviced and the packet is read from the buffer RAM and
sent to the transmit MAC. If there are multiple queues that require servicing, one of two methods may
be used: fixed priority ordering, or weighted round-robin ordering. If the Fixed Priority Queue Servicing
bit in the Buffer Manager Configuration Register (BM_CFG) is set, a strict order, fixed priority is
selected. Transmit queue 3 has the highest priority, followed by 2, 1, and 0. If the Fixed Priority Queue
Servicing bit in the Buffer Manager Configuration Register (BM_CFG) is cleared, a weighted round-
robin order is followed. Assuming all four queues are non-empty, the service is weighted with a 9:4:2:1
ratio (queue 3,2,1,0). The servicing is blended to avoid burstiness (e.g. queue 3, then queue 2, then
queue 3, etc.).
6.5.5 Egress Rate Limiting (Leaky Bucket)
For egress rate limiting, the leaky bucket algorithm is used on each output priority queue. For each
output port, the bandwidth that is used by each priority queue can be limited. If any egress queue
receives packets faster than the specified egress rate, packets will be accumulated in the packet
memory. After the memory is used, packet dropping or flow control will be triggered.
Note: Egress rate limiting occurs before the Transmit Priority Queue Servicing, such that a lower
priority queue will be serviced if a higher priority queue is being rate limited.
The egress limiting is enabled per priority queue. After a packet is selected to be sent, its length is
recorded. The switch then waits a programmable amount of time, scaled by the packet length, before
servicing that queue once again. The amount of time per byte is programmed into the Buffer Manager
Egress Rate registers (refer to Section 13.4.4.14 through Section 13.4.4.19 for detailed register
definitions). The value programmed is in approximately 20 nS per byte increments. Typical values are
listed in Table 6. 5 . When a port is transmitting at 10 Mbps, any setting above 39 has the effect of not
limiting the rate.
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Note 6.3 These are the unlimited max bandwidths when IFG and preamble are taken into account.
6.5.6 Adding, Removing, and Changing VLAN Tags
Based on the port configuration and the received packet formation, a VLAN tag can be added to,
removed from, or modified in a packet. There are four received packet type cases: non-tagged, priority-
tagged, normal-tagged, and CPU special-tagged. There are also four possible settings for an egress
port: dumb, access, hybrid, and CPU. In addition, each VLAN table entry can specify the removal of
the VLAN tag (the entry’s un-tag bit).
The tagging/un-tagging rules are specified as follows:
Dumb Port - This port type generally does not change the tag.
When a received packet is non-tagged, priority-tagged, or normal-tagged, the packet passes
untouched.
When a packet is received special-tagged from a CPU port, the special tag is removed.
Access Port - This port type generally does not support tagging.
When a received packet in non-tagged, the packet passes untouched.
When a received packet is priority-tagged or normal-tagged, the tag is removed.
When a received packet is special-tagged from a CPU port, the special tag is removed.
CPU Port - Packets transmitted from this port type generally contain a special tag. Special tags
are described in detail in Section 6.4.10, "Host CPU Port Special Tagging," on page 88.
Hybrid Port - Generally, this port type supports a mix of normal-tagged and non-tagged packets.
It is the most complex, but most flexible port type.
Table 6.5 Typical Egress Rate Settings
EGRESS RATE
SETTING TIME PER BYTE
BANDWIDTH @
64 BYTE PACKET
BANDWIDTH @
512 BYTE PACKET
BANDWIDTH @
1518 BYTE PACKET
0-3 80 nS 76 Mbps (Note 6.3) 96 Mbps (Note 6.3)99 Mbps (Note 6.3)
4 100 nS 66 Mbps 78 Mbps 80 Mbps
5 120 nS 55 Mbps 65 Mbps 67 Mbps
6 140 nS 48 Mbps 56 Mbps 57 Mbps
7 160 nS 42 Mbps 49 Mbps 50 Mbps
9 200 nS 34 Mbps 39 Mbps 40 Mbps
12 260 nS 26 Mbps 30 Mbps 31 Mbps
19 400 nS 17 Mbps 20 Mbps 20 Mbps
39 800 nS 8.6 Mbps 10 Mbps 10 Mbps
78 1580 nS 4.4 Mbps 5 Mbps 5 Mbps
158 3180 nS 2.2 Mbps 2.5 Mbps 2.5 Mbps
396 7940 nS 870 Kbps 990 Kbps 1 Mbps
794 15900 nS 440 Kbps 490 Kbps 500 Kbps
1589 31800 nS 220 Kbps 250 Kbps 250 Kbps
3973 79480 nS 87 Kbps 98 Kbps 100 Kbps
7947 158960 nS 44 Kbps 49 Kbps 50 Kbps
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For clarity, the following details the incoming un-tag instruction. As described in Section 6.4.4, "VLAN
Support," on page 82, the un-tag instruction is the three un-tag bits from the applicable entry in the
VLAN table. The entry in the VLAN table is either the VLAN from the received packet or the ingress
port’s default VID.
When a received packet is non-tagged, a new VLAN tag is added if two conditions are met. First,
the Insert Tag bit for the egress port in the Buffer Manager Egress Port Type Register
(BM_EGRSS_PORT_TYPE) must be set. Second, the un-tag bit, for the egress port, from the un-
tag instruction associated with the ingress port’s default VID, must be cleared. The VLAN tag that
is added will have a VID taken from either the ingress or egress port’s default VID. The priority of
the VLAN tag is either the priority calculated on ingress or the egress port’s default. The choice of
ingress or egress is determined by the egress port’s VID/Priority Select bit in the Buffer Manager
Egress Port Type Register (BM_EGRSS_PORT_TYPE).
When a received packet is priority-tagged, either the tag is removed or it is modified.
If the un-tag bit, for the egress port, from the un-tag instruction associated with the ingress port’s
default VID is set, then the tag is removed.
Otherwise, the tag is modified. The VID of the new VLAN tag is changed to either the ingress or
egress port’s default VID. If the Change Priority bit in the Buffer Manager Egress Port Type Register
(BM_EGRSS_PORT_TYPE) for the egress port is set, then the Priority field of the new VLAN tag
is also changed. The priority of the VLAN tag is either the priority calculated on ingress or the
egress port’s default. The choice of ingress or egress is determined by the egress port’s
VID/Priority Select bit.
When a received packet is normal-tagged, either the tag is removed, modified, or passed
unchanged.
If the un-tag bit, for the egress port, from the un-tag instruction associated with the VID in the
received packet is set, then the tag is removed.
Else, if the Change Tag bit in the Buffer Manager Egress Port Type Register
(BM_EGRSS_PORT_TYPE) for the egress port is clear, the packet passes untouched.
Else, if both the Change VLAN ID and the Change Priority bits in the Buffer Manager Egress Port
Type Register (BM_EGRSS_PORT_TYPE) for the egress port are clear, the packet passes
untouched.
Otherwise, the tag is modified. If the Change VLAN ID bit for the egress port is set, the VID of the
new VLAN tag is changed to either the ingress or egress port’s default VID. If the Change Priority
bit for the egress port is set, the Priority field of the new VLAN tag is changed to either the priority
calculated on ingress or the egress port’s default. The choice of ingress or egress is determined
by the egress port’s VID / Priority Select bit.
When a packet is received special-tagged from a CPU port, the special tag is removed.
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Hybrid tagging is summarized in Figure 6.9.
The default VLAN ID and priority of each port may be configured via the following registers:
Buffer Manager Port 0 Default VLAN ID and Priority Register (BM_VLAN_0)
Buffer Manager Port 1 Default VLAN ID and Priority Register (BM_VLAN_1)
Buffer Manager Port 2 Default VLAN ID and Priority Register (BM_VLAN_2)
Figure 6.9 Hybrid Port Tagging and Un-tagging
Insert Tag
[egress_port]
Default VID
[ingress_port]
Un-tag Bit
Y
Non-tagged
Y
Add Tag
VID = Default VID
[ingress_port or egress port*]
Priority = ingress priority or
Default Priority
[egress_port]*
Y
Send Packet Untouched
N
Priority Tagged
Default VID
[ingress_port]
Un-tag Bit
Y
Strip Tag
N
Normal Tagged
Received VID
Un-tag Bit
Y
Strip Tag
Change Tag
[egress_port]
N
N
Send Packet Untouched
Y
Change Priority
[egress_port]
Modify Tag
VID = Default VID
[ingress_port or egress port*]
Priority = ingress priority or
Default Priority [egress_port]*
N
Change VLAN ID
[egress_port]
Change Priority
[egress_port]
Change Priority
[egress_port]
Y N
N
Modify Tag
VID = Default VID [ingress
port or egress_port*]
Priority = ingress priority or
Default Priority
[egress_port]*
Y
Modify Tag
VID = Default VID [ingress
port or egress_port*]
Priority = Unchanged
N Y
Modify Tag
VID = Unchanged
Priority = ingress priority or
Default Priority
[egress_port]*
Special Tagged
Strip Tag
Modify Tag
VID = Default VID
[ingress_port or egress port*]
Priority = Unchanged
N
Receive Tag
Type
*choosen by VID /
Priority Select bit
*choosen by VID /
Priority Select bit
*choosen by VID /
Priority Select bit
*choosen by VID /
Priority Select bit
*choosen by VID /
Priority Select bit
*choosen by VID /
Priority Select bit
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6.5.7 Counters
A counter is maintained per port that contains the number of packets dropped due to buffer space limits
and ingress rate limit discarding (Red and random Yellow dropping). These counters are accessible
via the following registers:
Buffer Manager Port 0 Drop Count Register (BM_DRP_CNT_SRC_0)
Buffer Manager Port 1 Drop Count Register (BM_DRP_CNT_SRC_1)
Buffer Manager Port 2 Drop Count Register (BM_DRP_CNT_SRC_2)
A counter is maintained per port that contains the number of packets dropped due solely to ingress
rate limit discarding (Red and random Yellow dropping). This count value can be subtracted from the
drop counter, as described above, to obtain the drop counts due solely to buffer space limits. The
ingress rate drop counters are accessible via the following registers:
Buffer Manager Port 0 Ingress Rate Drop Count Register (BM_RATE_DRP_CNT_SRC_0)
Buffer Manager Port 1 Ingress Rate Drop Count Register (BM_RATE_DRP_CNT_SRC_1)
Buffer Manager Port 2 Ingress Rate Drop Count Register (BM_RATE_DRP_CNT_SRC_2)
6.6 Switch Fabric Interrupts
The Switch Fabric is capable of generating multiple maskable interrupts from the Buffer Manager,
Switch Engine, and MACs. These interrupts are detailed in Section 5.2.1, "Switch Fabric Interrupts,"
on page 64.
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Chapter 7 Ethernet PHYs
7.1 Functional Overview
The device contains three PHYs: Port 1 PHY, Port 2 PHY and a Virtual PHY. The Port 1 & 2 PHYs
are identical in functionality and each connect their corresponding Ethernet signal pins to the Switch
Fabric MAC of their respective port. These PHYs interface with their respective MAC via an internal
MII interface. The Virtual PHY provides the virtual functionality of a PHY and allows connection of an
external MAC to Port 0 of the Switch Fabric as if it was connected to a single port PHY. The Port 1
PHY may optionally be bypassed for the connection of an external MAC or PHY via the Port 1 MII/RMII
interface. All PHYs comply with the IEEE 802.3 Physical Layer for Twisted Pair Ethernet and can be
configured for full/half duplex 100 Mbps (100BASE-TX) or 10Mbps (10BASE-T) Ethernet operation. All
PHY registers follow the IEEE 802.3 (clause 22.2.4) specified MII management register set and can
be configured indirectly via the external MII interface signals, or directly via the memory mapped Virtual
PHY registers. In addition, the Port 1 PHY and Port 2 PHY can be configured via the PHY
Management Interface (PMI). Refer to Section 13.3, "Ethernet PHY Control and Status Registers" for
details on the Ethernet PHY registers.
The Ethernet PHYs are discussed in detail in the following sections:
Section 7.2, "Port 1 & 2 PHYs," on page 97
Section 7.3, "Virtual PHY," on page 110
7.1.1 PHY Addressing
Each individual PHY is assigned a unique default PHY address via the phy_addr_sel_strap
configuration strap as shown in Ta b l e 7 . 1 . In addition, the Port 1 PHY and Port 2 PHY addresses can
be changed via the PHY Address (PHYADD) field in the Port x PHY Special Modes Register
(PHY_SPECIAL_MODES_x). For proper operation, all PHY addresses must be unique. No check is
performed to assure each PHY is set to a different address. Configuration strap values are latched
upon the de-assertion of a chip-level reset as described in Section 4.2.4, "Configuration Straps," on
page 52.
Table 7.1 Default PHY Serial MII Addressing
phy_addr_sel_strap
VIRTUAL PHY DEFAULT
ADDRESS VALUE
PORT 1 PHY DEFAULT
ADDRESS VALUE
PORT 2 PHY DEFAULT
ADDRESS VALUE
0012
1123
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7.2 Port 1 & 2 PHYs
The Port 1 and Port 2 PHYs are functionally identical. The Port 1 PHY is active when Port 1 is
operating in Internal PHY mode. The Port 1 PHY may optionally be bypassed for the connection of an
external MAC or PHY via the Port 1 MII/RMII interface. Each PHY can be divided into the following
functional sections:
100BASE-TX Transmit and 100BASE-TX Receive
10BASE-T Transmit and 10BASE-T Receive
PHY Auto-negotiation
HP Auto-MDIX
MII MAC Interface
PHY Management Control
Note 7.1 Because the Port 1 PHY and Port 2 PHY are functionally identical, this section will describe
them as the “Port x PHY”, or simply “PHY”. Wherever a lowercase “x” has been appended
to a port or signal name, it can be replaced with “1” or “2” to indicate the Port 1 or Port 2
PHY respectively. All references to “PHY” in this section can be used interchangeably for
both the Port 1 & 2 PHYs. This nomenclature excludes the Virtual PHY.
A block diagram of the Port x PHYs main components can be seen in Figure 7.1.
Figure 7.1 Port x PHY Block Diagram
HP Auto-MDIX
TXPx/TXNx
RXPx/RXNx
To External
Port x Ethernet Pins
10/100
Transmitter
10/100
Reciever
MII
MAC
Interface
MII
MDIO
Auto-
Negotiation
To Port x
Switch Fabric MAC
To MII Mux
LEDs PLL
PHY Management
Control
Registers
From
System Clocks Controller
To GPIO/LED
Controller
Interrupts
To System
Interrupt Controller
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7.2.1 100BASE-TX Transmit
The 100BASE-TX transmit data path is shown in Figure 7.2. Shaded blocks are those which are
internal to the PHY. Each major block is explained in the following sections.
7.2.1.1 MII MAC Interface
For a transmission, the Switch Fabric MAC drives the transmit data to the PHYs MII MAC Interface.
The MII MAC Interface is described in detail in Section 7.2.7, "MII MAC Interface".
Note: The PHY is connected to the Switch Fabric MAC via standard MII signals. Refer to the IEEE
802.3 specification for additional details.
7.2.1.2 4B/5B Encoder
The transmit data passes from the MII block to the 4B/5B Encoder. This block encodes the data from
4-bit nibbles to 5-bit symbols (known as “code-groups”) according to Ta ble 7. 2 . Each 4-bit data-nibble
is mapped to 16 of the 32 possible code-groups. The remaining 16 code-groups are either used for
control information or are not valid.
The first 16 code-groups are referred to by the hexadecimal values of their corresponding data nibbles,
0 through F. The remaining code-groups are given letter designations with slashes on either side. For
example, an IDLE code-group is /I/, a transmit error code-group is /H/, etc.
Figure 7.2 100BASE-TX Transmit Data Path
Port x
MAC
100M
TX Driver
MLT-3
Converter
NRZI
Converter
4B/5B
Encoder
Magnetics
CAT-5RJ45
100M
PLL
Internal
MII 25 MHz by 4 bits
Internal
MII Transmit Clock
25MHz by
5 bits
NRZI
MLT-3
MLT-3
MLT-3
MLT-3
Scrambler
and PISO
125 Mbps Serial
MII MAC
Interface
25MHz
by 4 bits
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Table 7.2 4B/5B Code Table
CODE
GROUP SYM
RECEIVER
INTERPRETATION
TRANSMITTER
INTERPRETATION
11110 0 0 0000 DATA 0 0000 DATA
01001 1 1 0001 1 0001
10100 2 2 0010 2 0010
10101 3 3 0011 3 0011
01010 4 4 0100 4 0100
01011 5 5 0101 5 0101
01110 6 6 0110 6 0110
01111 7 7 0111 7 0111
10010 8 8 1000 8 1000
10011 9 9 1001 9 1001
10110 A A 1010 A 1010
10111 B B 1011 B 1011
11010 C C 1100 C 1100
11011 D D 1101 D 1101
11100 E E 1110 E 1110
11101 F F 1111 F 1111
11111 /I/ IDLE Sent after /T/R/ until the MII Transmitter
Enable signal (TXEN) is received
11000 /J/ First nibble of SSD, translated to “0101”
following IDLE, else MII Receive Error
(RXER)
Sent for rising MII Transmitter Enable
signal (TXEN)
10001 /K/ Second nibble of SSD, translated to
“0101” following /J/, else MII Receive
Error (RXER)
Sent for rising MII Transmitter Enable
signal (TXEN)
01101 /T/ First nibble of ESD, causes de-assertion
of CRS if followed by /R/, else assertion
of MII Receive Error (RXER)
Sent for falling MII Transmitter Enable
signal (TXEN)
00111 /R/ Second nibble of ESD, causes de-
assertion of CRS if following /T/, else
assertion of MII Receive Error (RXER)
Sent for falling MII Transmitter Enable
signal (TXEN)
00100 /H/ Transmit Error Symbol Sent for rising MII Transmit Error (TXER)
00110 /V/ INVALID, MII Receive Error (RXER) if
during MII Receive Data Valid (RXDV)
INVALID
11001 /V/ INVALID, MII Receive Error (RXER) if
during MII Receive Data Valid (RXDV)
INVALID
00000 /V/ INVALID, MII Receive Error (RXER) if
during MII Receive Data Valid (RXDV)
INVALID
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7.2.1.3 Scrambler and PISO
Repeated data patterns (especially the IDLE code-group) can have power spectral densities with large
narrow-band peaks. Scrambling the data helps eliminate these peaks and spread the signal power
more uniformly over the entire channel bandwidth. This uniform spectral density is required by FCC
regulations to prevent excessive EMI from being radiated by the physical wiring. The scrambler also
performs the Parallel In Serial Out conversion (PISO) of the data.
The seed for the scrambler is generated from the PHY address, ensuring that each PHY will have its
own scrambler sequence. For more information on PHY addressing, refer to Section 7.1.1, "PHY
Addressing".
7.2.1.4 NRZI and MLT-3 Encoding
The scrambler block passes the 5-bit wide parallel data to the NRZI converter where it becomes a
serial 125MHz NRZI data stream. The NRZI is then encoded to MLT-3. MLT-3 is a tri-level code where
a change in the logic level represents a code bit “1” and the logic output remaining at the same level
represents a code bit “0”.
7.2.1.5 100M Transmit Driver
The MLT-3 data is then passed to the analog transmitter, which drives the differential MLT-3 signal on
output pins TXPx and TXNx (where “x” is replaced with “1” for the Port 1 PHY, or “2” for the Port 2
PHY), to the twisted pair media across a 1:1 ratio isolation transformer. The 10BASE-T and 100BASE-
TX signals pass through the same transformer so that common “magnetics” can be used for both. The
transmitter drives into the 100Ω impedance of the CAT-5 cable. Cable termination and impedance
matching require external components.
7.2.1.6 100M Phase Lock Loop (PLL)
The 100M PLL locks onto the reference clock and generates the 125MHz clock used to drive the 125
MHz logic and the 100BASE-TX Transmitter.
00001 /V/ INVALID, MII Receive Error (RXER) if
during MII Receive Data Valid (RXDV)
INVALID
00010 /V/ INVALID, MII Receive Error (RXER) if
during MII Receive Data Valid (RXDV)
INVALID
00011 /V/ INVALID, MII Receive Error (RXER) if
during MII Receive Data Valid (RXDV)
INVALID
00101 /V/ INVALID, MII Receive Error (RXER) if
during MII Receive Data Valid (RXDV)
INVALID
01000 /V/ INVALID, MII Receive Error (RXER) if
during MII Receive Data Valid (RXDV)
INVALID
01100 /V/ INVALID, MII Receive Error (RXER) if
during MII Receive Data Valid (RXDV)
INVALID
10000 /V/ INVALID, MII Receive Error (RXER) if
during MII Receive Data Valid (RXDV)
INVALID
Table 7.2 4B/5B Code Table (continued)
CODE
GROUP SYM
RECEIVER
INTERPRETATION
TRANSMITTER
INTERPRETATION
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7.2.2 100BASE-TX Receive
The 100BASE-TX receive data path is shown in Figure 7.3. Shaded blocks are those which are internal
to the PHY. Each major block is explained in the following sections.
7.2.2.1 A/D Converter
The MLT-3 data from the cable is fed into the PHY on inputs RXPx and RXNx (where “x” is replaced
with “1” for the Port 1 PHY, or “2” for the Port 2 PHY) via a 1:1 ratio transformer. The ADC samples
the incoming differential signal at a rate of 125M samples per second. Using a 64-level quantizer, 6
digital bits are generated to represent each sample. The DSP adjusts the gain of the A/D Converter
(ADC) according to the observed signal levels such that the full dynamic range of the ADC can be
used.
7.2.2.2 DSP: Equalizer, BLW Correction and Clock/Data Recovery
The 6 bits from the ADC are fed into the DSP block. The equalizer in the DSP section compensates
for phase and amplitude distortion caused by the physical channel (magnetics, connectors, and CAT-
5 cable). The equalizer can restore the signal for any good-quality CAT-5 cable between 1m and 150m.
If the DC content of the signal is such that the low-frequency components fall below the low frequency
pole of the isolation transformer, then the droop characteristics of the transformer will become
significant and Baseline Wander (BLW) on the received signal will result. To prevent corruption of the
received data, the PHY corrects for BLW and can receive the ANSI X3.263-1995 FDDI TP-PMD
defined “killer packet” with no bit errors.
The 100M PLL generates multiple phases of the 125MHz clock. A multiplexer, controlled by the timing
unit of the DSP, selects the optimum phase for sampling the data. This is used as the received
recovered clock. This clock is used to extract the serial data from the received signal.
Figure 7.3 100BASE-TX Receive Data Path
Port x
MAC
A/D
Converter
MLT-3
Converter
NRZI
Converter
4B/5B
Decoder
Magnetics CAT-5RJ45
100M
PLL
Internal
MII 25MHz by 4 bits
Internal
MII Receive Clock
25MHz by
5 bits
NRZI
MLT-3MLT-3 MLT-3
6 bit Data
Descrambler
and SIPO
125 Mbps Serial
DSP: Timing
recovery, Equalizer
and BLW Correction
MLT-3
MII MAC
Interface
25MHz
by 4 bits
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7.2.2.3 NRZI and MLT-3 Decoding
The DSP generates the MLT-3 recovered levels that are fed to the MLT-3 converter. The MLT-3 is then
converted to an NRZI data stream.
7.2.2.4 Descrambler and SIPO
The descrambler performs an inverse function to the scrambler in the transmitter and also performs
the Serial In Parallel Out (SIPO) conversion of the data.
During reception of IDLE (/I/) symbols. the descrambler synchronizes its descrambler key to the
incoming stream. Once synchronization is achieved, the descrambler locks on this key and is able to
descramble incoming data.
Special logic in the descrambler ensures synchronization with the remote PHY by searching for IDLE
symbols within a window of 4000 bytes (40us). This window ensures that a maximum packet size of
1514 bytes, allowed by the IEEE 802.3 standard, can be received with no interference. If no IDLE-
symbols are detected within this time-period, receive operation is aborted and the descrambler re-starts
the synchronization process.
The de-scrambled signal is then aligned into 5-bit code-groups by recognizing the /J/K/ Start-of-Stream
Delimiter (SSD) pair at the start of a packet. Once the code-word alignment is determined, it is stored
and utilized until the next start of frame.
7.2.2.5 5B/4B Decoding
The 5-bit code-groups are translated into 4-bit data nibbles according to the 4B/5B table shown in
Table 7.2. The translated data is presented on the internal MII RXD[3:0] signal lines to the Switch
Fabric MAC. The SSD, /J/K/, is translated to “0101 0101” as the first 2 nibbles of the MAC preamble.
Reception of the SSD causes the PHY to assert the RXDV signal, indicating that valid data is available
on the RXD bus. Successive valid code-groups are translated to data nibbles. Reception of either the
End of Stream Delimiter (ESD) consisting of the /T/R/ symbols, or at least two /I/ symbols causes the
PHY to de-assert carrier sense and RXDV. These symbols are not translated into data.
7.2.2.6 Receiver Errors
During a frame, unexpected code-groups are considered receive errors. Expected code groups are the
DATA set (0 through F), and the /T/R/ (ESD) symbol pair. When a receive error occurs, the internal
MII’s RXER signal is asserted and arbitrary data is driven onto the internal receive data bus (RXD) to
the Switch Fabric MAC. Should an error be detected during the time that the /J/K/ delimiter is being
decoded (bad SSD error), RXER is asserted and the value 1110b is driven onto the internal receive
data bus (RXD) to the Switch Fabric MAC. Note that the internal MII’s data valid signal (RXDV) is not
yet asserted when the bad SSD occurs.
7.2.2.7 MII MAC Interface
For reception, the 4-bit data nibbles are sent to the MII MAC Interface block where they are sent via
MII to the Switch Fabric MAC. The MII MAC Interface is described in detail in Section 7.2.7, "MII MAC
Interface".
Note: The PHY is connected to the Switch Fabric MAC via standard MII signals. Refer to the IEEE
802.3 specification for additional details.
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7.2.3 10BASE-T Transmit
Data to be transmitted comes from the Switch Fabric MAC. The 10BASE-T transmitter receives 4-bit
nibbles from the internal MII at a rate of 2.5MHz and converts them to a 10Mbps serial data stream.
The data stream is then Manchester-encoded and sent to the analog transmitter, which drives a signal
onto the twisted pair via the external magnetics.
10BASE-T transmissions use the following blocks:
MII MAC Interface (digital)
10M TX Driver (digital/analog)
10M PLL (analog)
7.2.3.1 MII MAC Interface
For a transmission, the Switch Fabric MAC drives the transmit data to the PHYs MII MAC Interface.
The MII MAC Interface is described in detail in Section 7.2.7, "MII MAC Interface".
Note: The PHY is connected to the Switch Fabric MAC via standard MII signals. Refer to the IEEE
802.3 specification for additional details.
7.2.3.2 10M TX Driver and PLL
The 4-bit wide data is sent to the 10M TX Driver block. The nibbles are converted to a 10Mbps serial
NRZI data stream. The 10M PLL locks onto the external clock or internal oscillator and produces a
20MHz clock. This is used to Manchester encode the NRZ data stream. When no data is being
transmitted (TXEN is low), the 10M TX Driver block outputs Normal Link Pulses (NLPs) to maintain
communications with the remote link partner. The manchester encoded data is sent to the analog
transmitter where it is shaped and filtered before being driven out as a differential signal across the
TXPx and TXNx outputs (where “x” is replaced with “1” for the Port 1 PHY, or “2” for the Port 2 PHY).
7.2.4 10BASE-T Receive
The 10BASE-T receiver gets the Manchester-encoded analog signal from the cable via the magnetics.
It recovers the receive clock from the signal and uses this clock to recover the NRZI data stream. This
10M serial data is converted to 4-bit data nibbles which are passed to the controller across the internal
MII at a rate of 2.5MHz.
10BASE-T reception uses the following blocks:
Filter and SQUELCH (analog)
10M RX (digital/analog)
MII MAC Interface (digital)
10M PLL (analog)
7.2.4.1 Filter and Squelch
The Manchester signal from the cable is fed into the PHY on inputs RXPx and RXNx (where “x” is
replaced with “1” for Port 1, or “2” for Port 2) via 1:1 ratio magnetics. It is first filtered to reduce any
out-of-band noise. It then passes through a SQUELCH circuit. The SQUELCH is a set of amplitude
and timing comparators that normally reject differential voltage levels below 300mV and detect and
recognize differential voltages above 585mV.
7.2.4.2 10M RX and PLL
The output of the SQUELCH goes to the 10M RX block where it is validated as Manchester encoded
data. The polarity of the signal is also checked. If the polarity is reversed (local RXP is connected to
RXN of the remote partner and vice versa), then this is identified and corrected. The reversed condition
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is indicated by the 10Base-T Polarity State (XPOL) in the Port x PHY Special Control/Status Indication
Register (PHY_SPECIAL_CONTROL_STAT_IND_x). The 10M PLL locks onto the received
Manchester signal and generates the received 20MHz clock from it. Using this clock, the Manchester
encoded data is extracted and converted to a 10MHz NRZI data stream. It is then converted from serial
to 4-bit wide parallel data.
The RX10M block also detects valid 10BASE-T IDLE signals - Normal Link Pulses (NLPs) - to maintain
the link.
7.2.4.3 MII MAC Interface
For reception, the 4-bit data nibbles are sent to the MII MAC Interface block where they are sent via
MII to the Switch Fabric MAC. The MII MAC Interface is described in detail in Section 7.2.7, "MII MAC
Interface".
Note: The PHY is connected to the Switch Fabric MAC via standard MII signals. Refer to the IEEE
802.3 specification for additional details.
7.2.4.4 Jabber Detection
Jabber is a condition in which a station transmits for a period of time longer than the maximum
permissible packet length, usually due to a fault condition, that results in holding the TXEN input for
an extended period of time. Special logic is used to detect the jabber state and abort the transmission
to the line, within 45ms. Once TXEN is deasserted, the logic resets the jabber condition.
7.2.5 PHY Auto-negotiation
The purpose of the auto-negotiation function is to automatically configure the PHY to the optimum link
parameters based on the capabilities of its link partner. Auto-negotiation is a mechanism for
exchanging configuration information between two link-partners and automatically selecting the highest
performance mode of operation supported by both sides. Auto-negotiation is fully defined in clause 28
of the IEEE 802.3 specification and is enabled by setting the Auto-Negotiation (PHY_AN) bit of the
Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x).
The advertised capabilities of the PHY are stored in the Port x PHY Auto-Negotiation Advertisement
Register (PHY_AN_ADV_x). The PHY contains the ability to advertise 100BASE-TX and 10BASE-T in
both full or half-duplex modes. Besides the connection speed, the PHY can advertise remote fault
indication and symmetric or asymmetric pause flow control as defined in the IEEE 802.3 specification.
“Next Page” capability is not supported. Many of the default advertised capabilities of the PHY are
determined via configuration straps as shown in Section 13.3.2.5, "Port x PHY Auto-Negotiation
Advertisement Register (PHY_AN_ADV_x)," on page 214. Refer to Section 4.2.4, "Configuration
Straps," on page 52 for additional details on the configuration straps.
Once auto-negotiation has completed, information about the resolved link and the results of the
negotiation process are reflected in the speed indication bits in the Port x PHY Special Control/Status
Register (PHY_SPECIAL_CONTROL_STATUS_x), as well as the Port x PHY Auto-Negotiation Link
Partner Base Page Ability Register (PHY_AN_LP_BASE_ABILITY_x).
The auto-negotiation protocol is a purely physical layer activity and proceeds independently of the MAC
controller.
The following blocks are activated during an Auto-negotiation session:
Auto-negotiation (digital)
100M ADC (analog)
100M PLL (analog)
100M equalizer/BLW/clock recovery (DSP)
10M SQUELCH (analog)
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10M PLL (analog)
10M TX Driver (analog)
Auto-negotiation is started by the occurrence of any of the following events:
Power-On Reset (POR)
Hardware reset (nRST)
PHY Software reset (via Reset Control Register (RESET_CTL), or the Reset (PHY_RST) bit of the
Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x))
PHY Power-down reset (Section 7.2.9, "PHY Power-Down Modes," on page 109)
PHY Link status down (the Link Status bit of the Port x PHY Basic Status Register
(PHY_BASIC_STATUS_x) is cleared)
Setting the Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x), Restart Auto-
Negotiation (PHY_RST_AN) bit high
Digital Reset (via the Digital Reset (DIGITAL_RST) bit of the Reset Control Register (RESET_CTL))
Issuing an EEPROM Loader RELOAD command (Section 8.4, "EEPROM Loader," on page 121)
Note: Refer to Section 4.2, "Resets," on page 48 for information on these and other system resets.
On detection of one of these events, the PHY begins auto-negotiation by transmitting bursts of Fast
Link Pulses (FLP). These are bursts of link pulses from the 10M TX Driver. They are shaped as Normal
Link Pulses and can pass uncorrupted down CAT-3 or CAT-5 cable. A Fast Link Pulse Burst consists
of up to 33 pulses. The 17 odd-numbered pulses, which are always present, frame the FLP burst. The
16 even-numbered pulses, which may be present or absent, contain the data word being transmitted.
Presence of a data pulse represents a “1”, while absence represents a “0”.
The data transmitted by an FLP burst is known as a “Link Code Word.” These are defined fully in IEEE
802.3 clause 28. In summary, the PHY advertises 802.3 compliance in its selector field (the first 5 bits
of the Link Code Word). It advertises its technology ability according to the bits set in the Port x PHY
Auto-Negotiation Advertisement Register (PHY_AN_ADV_x).
There are 4 possible matches of the technology abilities. In the order of priority these are:
100M Full Duplex (highest priority)
100M Half Duplex
10M Full Duplex
10M Half Duplex (lowest priority)
If the full capabilities of the PHY are advertised (100M, full-duplex), and if the link partner is capable
of 10M and 100M, then auto-negotiation selects 100M as the highest performance mode. If the link
partner is capable of half and full-duplex modes, then auto-negotiation selects full-duplex as the highest
performance mode.
Once a speed and duplex match has been determined, the link code words are repeated with the
acknowledge bit set. Any difference in the main content of the link code words at this time will cause
auto-negotiation to re-start. Auto-negotiation will also re-start if all of the required FLP bursts are not
received.
Writing the 10BASE-T Half Duplex, 10BASE-T Full Duplex, 100BASE-X Half Duplex, and 100BASE-X
Full Duplex bits of the Port x PHY Auto-Negotiation Advertisement Register (PHY_AN_ADV_x) allows
software control of the capabilities advertised by the PHY. Writing the Port x PHY Auto-Negotiation
Advertisement Register (PHY_AN_ADV_x) does not automatically re-start auto-negotiation. The Port
x PHY Basic Control Register (PHY_BASIC_CONTROL_x), Restart Auto-Negotiation (PHY_RST_AN)
bit must be set before the new abilities will be advertised. Auto-negotiation can also be disabled via
software by clearing the Auto-Negotiation (PHY_AN) bit of the Port x PHY Basic Control Register
(PHY_BASIC_CONTROL_x).
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7.2.5.1 PHY Pause Flow Control
The Port 1 & 2 PHYs are capable of generating and receiving pause flow control frames per the IEEE
802.3 specification. The PHYs advertised pause flow control abilities are set via the Symmetric Pause
and Asymmetric Pause bits of the Port x PHY Auto-Negotiation Advertisement Register
(PHY_AN_ADV_x). This allows the PHY to advertise its flow control abilities and auto-negotiate the
flow control settings with its link partner. The default values of these bits are determined via
configuration straps as defined in Section 13.3.2.5, "Port x PHY Auto-Negotiation Advertisement
Register (PHY_AN_ADV_x)," on page 214.
The pause flow control settings may also be manually set via the manual flow control registers Port 1
Manual Flow Control Register (MANUAL_FC_1) and Port 2 Manual Flow Control Register
(MANUAL_FC_2). These registers allow the Switch Fabric ports flow control settings to be manually
set when auto-negotiation is disabled or the respective manual flow control select bit is set (Port 1 Full-
Duplex Manual Flow Control Select (MANUAL_FC_1) for Port 1, Port 2 Full-Duplex Manual Flow
Control Select (MANUAL_FC_2) for Port 2). The currently enabled duplex and flow control settings can
also be monitored via these registers. The flow control values in the Port x PHY Auto-Negotiation
Advertisement Register (PHY_AN_ADV_x) are not affected by the values of the manual flow control
register. Refer to Section 6.2.3, "Flow Control Enable Logic," on page 70 for additional information.
7.2.5.2 Parallel Detection
If LAN9303M/LAN9303Mi is connected to a device lacking the ability to auto-negotiate (i.e. no FLPs
are detected), it is able to determine the speed of the link based on either 100M MLT-3 symbols or
10M Normal Link Pulses. In this case the link is presumed to be half-duplex per the IEEE 802.3
standard. This ability is known as “Parallel Detection.” This feature ensures interoperability with legacy
link partners. If a link is formed via parallel detection, then the Link Partner Auto-Negotiation Able bit
in the Port x PHY Auto-Negotiation Expansion Register (PHY_AN_EXP_x) is cleared to indicate that
the link partner is not capable of auto-negotiation. If a fault occurs during parallel detection, the Parallel
Detection Fault bit of the Port x PHY Auto-Negotiation Expansion Register (PHY_AN_EXP_x) is set.
The Port x PHY Auto-Negotiation Link Partner Base Page Ability Register
(PHY_AN_LP_BASE_ABILITY_x) is used to store the Link Partner Ability information, which is coded
in the received FLPs. If the link partner is not auto-negotiation capable, then this register is updated
after completion of parallel detection to reflect the speed capability of the link partner.
7.2.5.3 Restarting Auto-Negotiation
Auto-negotiation can be re-started at any time by setting the Restart Auto-Negotiation (PHY_RST_AN)
bit of the Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x). Auto-negotiation will also
re-start if the link is broken at any time. A broken link is caused by signal loss. This may occur because
of a cable break, or because of an interruption in the signal transmitted by the Link Partner. Auto-
negotiation resumes in an attempt to determine the new link configuration.
If the management entity re-starts Auto-negotiation by writing to the Restart Auto-Negotiation
(PHY_RST_AN) bit of the Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x), the device
will respond by stopping all transmission/receiving operations. Once the internal break link time of
approximately 1200ms has passed in the Auto-negotiation state-machine, the auto-negotiation will re-
start. In this case, the link partner will have also dropped the link due to lack of a received signal, so
it too will resume auto-negotiation.
7.2.5.4 Disabling Auto-Negotiation
Auto-negotiation can be disabled by clearing the Auto-Negotiation (PHY_AN) bit of the Port x PHY
Basic Control Register (PHY_BASIC_CONTROL_x). The PHY will then force its speed of operation to
reflect the speed (Speed Select LSB (PHY_SPEED_SEL_LSB)) and duplex (Duplex Mode
(PHY_DUPLEX)) of the Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x). The speed
and duplex bits in the Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x) should be
ignored when auto-negotiation is enabled.
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7.2.5.5 Half Vs. Full-Duplex
Half-duplex operation relies on the CSMA/CD (Carrier Sense Multiple Access / Collision Detect)
protocol to handle network traffic and collisions. In this mode, the carrier sense signal, CRS, responds
to both transmit and receive activity. If data is received while the PHY is transmitting, a collision results.
In full-duplex mode, the PHY is able to transmit and receive data simultaneously. In this mode, CRS
responds only to receive activity. The CSMA/CD protocol does not apply and collision detection is
disabled.
7.2.6 HP Auto-MDIX
HP Auto-MDIX facilitates the use of CAT-3 (10 BASE-T) or CAT-5 (100 BASE-T) media UTP
interconnect cable without consideration of interface wiring scheme. If a user plugs in either a direct
connect LAN cable or a cross-over patch cable, as shown in Figure 7.4 (See Note 7.1 on page 97),
the PHY is capable of configuring the TXPx/TXNx and RXPx/RXNx twisted pair pins for correct
transceiver operation.
The internal logic of the device detects the TX and RX pins of the connecting device. Since the RX
and TX line pairs are interchangeable, special PCB design considerations are needed to accommodate
the symmetrical magnetics and termination of an Auto-MDIX design.
The Auto-MDIX function can be disabled through the Auto-MDIX Control (AMDIXCTRL) bit of the Port
x PHY Special Control/Status Indication Register (PHY_SPECIAL_CONTROL_STAT_IND_x). When
Auto-MDIX Control (AMDIXCTRL) is cleared, Auto-MDIX can be selected via the Auto-MDIX Enable
configuration straps (auto_mdix_strap_1 and auto_mdix_strap_2 for Port 1 and Port 2, respectively).
The MDIX can also be configured manually via the Manual MDIX strap (manual_mdix_strap_1 and
manual_mdix_strap_2 for Port 1 and Port 2, respectively) if both the Auto-MDIX Control (AMDIXCTRL)
bit and the Auto-MDIX Enable configuration strap are low. Refer to Section 3.2, "Pin Descriptions," on
page 24 for more information on the configuration straps.
When the Auto-MDIX Control (AMDIXCTRL) bit of the Port x PHY Special Control/Status Indication
Register (PHY_SPECIAL_CONTROL_STAT_IND_x) is set to 1, the Auto-MDIX capability is determined
by the Auto-MDIX Enable (AMDIXEN) and Auto-MDIX State (AMDIXSTATE) bits of the Port x PHY
Special Control/Status Indication Register (PHY_SPECIAL_CONTROL_STAT_IND_x).
Figure 7.4 Direct Cable Connection vs. Cross-Over Cable Connection
1
2
3
4
5
6
7
8
TXPx
TXNx
RXPx
Not Used
Not Used
RXNx
Not Used
Not Used
1
2
3
4
5
6
7
8
TXPx
TXNx
RXPx
Not Used
Not Used
RXNx
Not Used
Not Used
Direct Connect Cable
RJ-45 8-pin straight-through
for 10BASE-T/100BASE-TX
signaling
1
2
3
4
5
6
7
8
TXPx
TXNx
RXPx
Not Used
Not Used
RXNx
Not Used
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TXPx
TXNx
RXPx
Not Used
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RXNx
Not Used
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Cross-Over Cable
RJ-45 8-pin cross-over for
10BASE-T/100BASE-TX
signaling
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7.2.7 MII MAC Interface
The MII MAC Interface is responsible for the transmission and reception of the Ethernet data to and
from the Switch Fabric MAC. The PHY is connected internally to the Switch Fabric MAC via standard
MII signals per IEEE 802.3.
For a transmission, the Switch Fabric MAC drives the transmit data onto the internal MII TXD bus and
asserts TXEN to indicate valid data. The data is in the form of 4-bit wide data at a rate of 25MHz for
100BASE-TX, or 2.5MHz for 10BASE-T.
For reception, the 4-bit data nibbles are sent to the MII MAC Interface block. These data nibbles are
clocked to the controller at a rate of 25MHz for 100BASE-TX, or 2.5MHz for 10BASE-T. RXCLK is the
output clock for the internal MII bus. It is recovered from the received data to clock the RXD bus. If
there is no received signal, it is derived from the system reference clock.
7.2.8 PHY Management Control
The PHY Management Control block is responsible for the management functions of the PHY,
including register access and interrupt generation. A Serial Management Interface (SMI) is used to
support registers 0 through 6 as required by the IEEE 802.3 (Clause 22), as well as the vendor specific
registers allowed by the specification. The SMI interface consists of the MII Management Data (MDIO)
signal and the MII Management Clock (MDC) signal. These signals interface to the MDIO and MDC
pins of LAN9303M/LAN9303Mi (or the PMI block in I2C mode of operation) and allow access to all
PHY registers. Refer to Section 13.3.2, "Port 1 & 2 PHY Registers," on page 206 for a list of all
supported registers and register descriptions. Non-supported registers will be read as FFFFh.
7.2.8.1 PHY Interrupts
The PHY contains the ability to generate various interrupt events as described in Table 7.3. Reading
the Port x PHY Interrupt Source Flags Register (PHY_INTERRUPT_SOURCE_x) shows the source of
the interrupt, and clears the interrupt signal. The Port x PHY Interrupt Mask Register
(PHY_INTERRUPT_MASK_x) enables or disables each PHY interrupt. The PHY Management Control
block aggregates the enabled interrupts status into an internal signal which is sent to the System
Interrupt Controller and is reflected via the Interrupt Status Register (INT_STS) bits Port 1 PHY
Interrupt Event (PHY_INT1) and Port 2 PHY Interrupt Event (PHY_INT2) for the Port 1 and Port 2
PHYs, respectively. For more information on interrupts, refer to Chapter 5, "System Interrupts," on
page 62.
Table 7.3 PHY Interrupt Sources
INTERRUPT SOURCE
PHY_INTERRUPT_MASK_x &
PHY_INTERRUPT_SOURCE_x REGISTER BIT #
ENERGYON Activated 7
Auto-Negotiation Complete 6
Remote Fault Detected 5
Link Down (Link Status Negated) 4
Auto-Negotiation LP Acknowledge 3
Parallel Detection Fault 2
Auto-Negotiation Page Received 1
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7.2.9 PHY Power-Down Modes
There are two power-down modes for the PHY:
PHY General Power-Down
PHY Energy Detect Power-Down
Note: For more information on the various power management features of the device, refer to Section
4.3, "Power Management," on page 61.
Note: The power-down modes of each PHY (Port 1 PHY and Port 2 PHY) are controlled
independently.
Note: The PHY power-down modes do not reload or reset the PHY registers.
7.2.9.1 PHY General Power-Down
This power-down mode is controlled by the Power Down (PHY_PWR_DWN) bit of the Port x PHY
Basic Control Register (PHY_BASIC_CONTROL_x). In this mode the entire PHY, except the PHY
management control interface, is powered down. The PHY will remain in this power-down state as long
as the bit is set. When the bit is cleared, the PHY powers up and is automatically reset.
Note: When the Port 1 external MII/RMII interface is selected, the Port 1 PHY is placed into the
general power-down mode.
7.2.9.2 PHY Energy Detect Power-Down
This power-down mode is enabled by setting the Energy Detect Power-Down (EDPWRDOWN) bit of
the Port x PHY Mode Control/Status Register (PHY_MODE_CONTROL_STATUS_x). When in this
mode, if no energy is detected on the line, the entire PHY is powered down except for the PHY
management control interface, the SQUELCH circuit, and the ENERGYON logic. The ENERGYON
logic is used to detect the presence of valid energy from 100BASE-TX, 10BASE-T, or auto-negotiation
signals and is responsible for driving the ENERGYON signal, whose state is reflected in the Energy
On (ENERGYON) bit of the Port x PHY Mode Control/Status Register
(PHY_MODE_CONTROL_STATUS_x).
In this mode, when the ENERGYON signal is cleared, the PHY is powered down and no data is
transmitted from the PHY. When energy is received, via link pulses or packets, the ENERGYON signal
goes high, and the PHY powers up. The PHY automatically resets itself into its previous state prior to
power-down, and asserts the INT7 interrupt bit of the Port x PHY Interrupt Source Flags Register
(PHY_INTERRUPT_SOURCE_x). The first and possibly second packet to activate ENERGYON may
be lost.
When the Energy Detect Power-Down (EDPWRDOWN) bit of the Port x PHY Mode Control/Status
Register (PHY_MODE_CONTROL_STATUS_x) is low, energy detect power-down is disabled.
7.2.10 PHY Resets
In addition to the chip-level hardware reset (nRST) and Power-On Reset (POR), the PHY supports
three block specific resets. These are discussed in the following sections. For detailed information on
all resets and the reset sequence refer to Section 4.2, "Resets," on page 48.
Note: The Digital Reset (DIGITAL_RST) bit in the Reset Control Register (RESET_CTL) does not
reset the PHYs. Only a hardware reset (nRST) or an EEPROM RELOAD command will
automatically reload the configuration strap values into the PHY registers. For all other PHY
resets, these values will need to be manually configured via software.
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7.2.10.1 PHY Software Reset via RESET_CTL
The PHY can be reset via the Reset Control Register (RESET_CTL). The Port 1 PHY is reset by
setting the Port 1 PHY Reset (PHY1_RST) bit, and the Port 2 PHY is reset by setting the Port 2 PHY
Reset (PHY2_RST) bit. These bits are self clearing after approximately 102uS. This reset does not
reload the configuration strap values into the PHY registers.
7.2.10.2 PHY Software Reset via PHY_BASIC_CTRL_x
The PHY can also be reset by setting the Reset (PHY_RST) bit of the Port x PHY Basic Control
Register (PHY_BASIC_CONTROL_x). This bit is self clearing and will return to 0 after the reset is
complete. This reset does not reload the configuration strap values into the PHY registers.
7.2.10.3 PHY Power-Down Reset
After the PHY has returned from a power-down state, a reset of the PHY is automatically generated.
The PHY power-down modes do not reload or reset the PHY registers. Refer to Section 7.2.9, "PHY
Power-Down Modes," on page 109 for additional information.
7.2.11 LEDs
Each PHY provides LED indication signals to the GPIO/LED block of the device. This allows external
LEDs to be used to indicate various PHY related functions such as TX/RX activity, speed, duplex, or
link status. Refer to Chapter 12, "GPIO/LED Controller," on page 144 for additional information on the
configuration of these signals.
7.2.12 Required Ethernet Magnetics
The magnetics selected for use with the device should be an Auto-MDIX style magnetic, which is
widely available from several vendors. Please review the SMSC Application note 8.13 “Suggested
Magnetics” for the latest qualified and suggested magnetics. A list of vendors and part numbers are
provided within the application note.
7.3 Virtual PHY
The Virtual PHY provides a basic MII management interface (MDIO) to the MII management pins per
the IEEE 802.3 (clause 22) so that a MAC with an unmodified driver can be supported as if the MAC
was attached to a single port PHY. This functionality is designed to allow easy and quick integration
of the device into designs with minimal driver modifications. The Virtual PHY provides a full bank of
registers which comply with the IEEE 802.3 specification. This enables the Virtual PHY to provide
various status and control bits similar to those provided by a real PHY. These include the output of
speed selection, duplex, loopback, isolate, collision test, and auto-negotiation status. For a list of all
Virtual PHY registers and related bit descriptions, refer to Section 13.3.1, "Virtual PHY Registers," on
page 206.
7.3.1 Virtual PHY Auto-Negotiation
The purpose of the auto-negotiation function is to automatically configure the Virtual PHY to the
optimum link parameters based on the capabilities of its link partner. Because the Virtual PHY has no
actual link partner, the auto-negotiation process is emulated with deterministic results.
Auto-negotiation is enabled by setting the Auto-Negotiation (VPHY_AN) bit of the Virtual PHY Basic
Control Register (VPHY_BASIC_CTRL) and is restarted by the occurrence of any of the following
events:
Power-On Reset (POR)
Hardware reset (nRST)
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PHY Software reset (via the Virtual PHY Reset (VPHY_RST) bit of the Reset Control Register
(RESET_CTL), or the Reset (VPHY_RST) bit of the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL))
Setting the Virtual PHY Basic Control Register (VPHY_BASIC_CTRL), Restart Auto-Negotiation
(VPHY_RST_AN) bit high
Digital Reset (via the Digital Reset (DIGITAL_RST) bit of the Reset Control Register (RESET_CTL))
Issuing an EEPROM Loader RELOAD command (Section 8.4, "EEPROM Loader," on page 121)
The emulated auto-negotiation process is much simpler than the real process and can be categorized
into three steps:
1. The Auto-Negotiation Complete bit is set in the Virtual PHY Basic Status Register
(VPHY_BASIC_STATUS).
2. The Page Received bit is set in the Virtual PHY Auto-Negotiation Expansion Register
(VPHY_AN_EXP).
3. The auto-negotiation result (speed, duplex, and pause) is determined and registered.
The auto-negotiation result (speed and duplex) is determined using the Highest Common Denominator
(HCD) of the Virtual PHY Auto-Negotiation Advertisement Register (VPHY_AN_ADV) and Virtual PHY
Auto-Negotiation Link Partner Base Page Ability Register (VPHY_AN_LP_BASE_ABILITY) as
specified in the IEEE 802.3 standard. The technology ability bits of these registers are ANDed, and if
there are multiple bits in common, the priority is determined as follows:
100Mbps Full Duplex (highest priority)
100Mbps Half Duplex
10Mbps Full Duplex
10Mbps Half Duplex (lowest priority)
For example, if the full capabilities of the Virtual PHY are advertised (100Mbps, Full Duplex), and if
the link partner is capable of 10Mbps and 100Mbps, then auto-negotiation selects 100Mbps as the
highest performance mode. If the link partner is capable of half and full-duplex modes, then auto-
negotiation selects full-duplex as the highest performance operation. In the event that there are no bits
in common, an emulated Parallel Detection is used.
The Virtual PHY Auto-Negotiation Advertisement Register (VPHY_AN_ADV) defaults to having all four
ability bits set. These values can be reconfigured via software. Once the auto-negotiation is complete,
any change to the Virtual PHY Auto-Negotiation Advertisement Register (VPHY_AN_ADV) will not take
affect until the auto-negotiation process is re-run. The emulated link partner default advertised abilities
in the Virtual PHY Auto-Negotiation Link Partner Base Page Ability Register
(VPHY_AN_LP_BASE_ABILITY) are dependant on the P0_DUPLEX pin and the duplex_pol_strap_0
and speed_strap_0 configuration straps as described in Table 13.7 of Section 13.2.6.6, "Virtual PHY
Auto-Negotiation Link Partner Base Page Ability Register (VPHY_AN_LP_BASE_ABILITY)," on
page 190. Neither the Virtual PHY or the emulated link partner support next page capability, remote
faults, or 100BASE-T4.
Note: The P0_DUPLEX, duplex_pol_strap_0, and speed_strap_0 inputs are considered to be static.
Auto-negotiation is not automatically re-evaluated if these inputs are changed.
If there is at least one common selection between the emulated link partner and the Virtual PHY
advertised abilities, then the auto-negotiation succeeds, the Link Partner Auto-Negotiation Able bit of
the Virtual PHY Auto-Negotiation Expansion Register (VPHY_AN_EXP) is set, and the technology
ability bits in the Virtual PHY Auto-Negotiation Link Partner Base Page Ability Register
(VPHY_AN_LP_BASE_ABILITY) are set to indicate the emulated link partners abilities.
Note: For the Virtual PHY, the auto-negotiation register bits (and management of such) are used by
the PMI. So the perception of local and link partner is reversed. The local device is the PMI,
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while the link partner is the Switch Fabric. This is consistent with the intention of the Virtual
PHY.
7.3.1.1 Parallel Detection
In the event that there are no common bits between the advertised ability and the emulated link
partners ability, auto-negotiation fails and emulated parallel detect is used. In this case, the Link
Partner Auto-Negotiation Able bit of the Virtual PHY Auto-Negotiation Expansion Register
(VPHY_AN_EXP) will be cleared, and the communication set to half-duplex. The speed is determined
by the speed_strap_0 configuration strap. Only one of the technology ability bits in the Virtual PHY
Auto-Negotiation Link Partner Base Page Ability Register (VPHY_AN_LP_BASE_ABILITY) will be set,
indicating the emulated parallel detect result.
7.3.1.2 Disabling Auto-Negotiation
Auto-negotiation can be disabled in the Virtual PHY by clearing the Auto-Negotiation (VPHY_AN) bit
of the Virtual PHY Basic Control Register (VPHY_BASIC_CTRL). The Virtual PHY will then force its
speed of operation to reflect the speed (Speed Select LSB (VPHY_SPEED_SEL_LSB) bit) and duplex
(Duplex Mode (VPHY_DUPLEX) bit) of the Virtual PHY Basic Control Register (VPHY_BASIC_CTRL).
The speed and duplex bits in the Virtual PHY Basic Control Register (VPHY_BASIC_CTRL) should be
ignored when auto-negotiation is enabled.
7.3.1.3 Virtual PHY Pause Flow Control
The Virtual PHY supports pause flow control per the IEEE 802.3 specification. The Virtual PHYs
advertised pause flow control abilities are set via the Symmetric Pause and Asymmetric Pause bits of
the Virtual PHY Auto-Negotiation Advertisement Register (VPHY_AN_ADV). This allows the Virtual
PHY to advertise its flow control abilities and auto-negotiate the flow control settings with the emulated
link partner. The default values of these bits are as shown in Section 13.2.6.5, "Virtual PHY Auto-
Negotiation Advertisement Register (VPHY_AN_ADV)," on page 188.
The symmetric/asymmetric pause ability of the emulated link partner is based upon the advertised
pause flow control abilities of the Virtual PHY as indicated in the Symmetric Pause and Asymmetric
Pause bits of the Virtual PHY Auto-Negotiation Advertisement Register (VPHY_AN_ADV). Thus, the
emulated link partner always accommodates the asymmetric/symmetric pause ability settings
requested by the Virtual PHY, as shown in Table 13.6, “Emulated Link Partner Pause Flow Control
Ability Default Values,” on page 191.
The pause flow control settings may also be manually set via the Port 0 Manual Flow Control Register
(MANUAL_FC_0). This register allows the Switch Fabric Port 0 flow control settings to be manually
set when auto-negotiation is disabled or the Port 0 Full-Duplex Manual Flow Control Select
(MANUAL_FC_0) bit is set. The currently enabled duplex and flow control settings can also be
monitored via this register. The flow control values in the Virtual PHY Auto-Negotiation Advertisement
Register (VPHY_AN_ADV) are not affected by the values of the manual flow control register. Refer to
Section 6.2.3, "Flow Control Enable Logic," on page 70 for additional information.
7.3.2 Virtual PHY in MAC Mode
In the MAC mode of operation, an external PHY is connected to the MII interface of the device.
Because there is an external PHY present, the Virtual PHY is not needed for external configuration.
However, the Port 0 Switch Fabric MAC still requires the proper duplex setting. Therefore, in MAC
mode, if the Auto-Negotiation (VPHY_AN) bit of the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL) is set, the duplex is based on the P0_DUPLEX pin and duplex_pol_strap_0
configuration strap. If these signals are equal, the Port 0 Switch Fabric MAC is configured for full-
duplex, otherwise it is set for half-duplex. The P0_DUPLEX pin is typically connected to the duplex
indication of the external PHY. The duplex is not latched since the auto-negotiation process is not used.
The duplex can be manually selected by clearing the Auto-Negotiation (VPHY_AN) bit and controlling
the Duplex Mode (VPHY_DUPLEX) bit in the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL).
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Note: In MAC mode, the Virtual PHY registers are accessible through their memory mapped registers
via the SMI or I2C serial management interfaces only. The Virtual PHY registers are not
accessible through MII management.
7.3.2.1 Full-Duplex Flow Control
In the MAC mode of operation, the Virtual PHY is not applicable. Therefore, full-duplex flow control
should be controlled manually by the host via the Port 0 Manual Flow Control Register
(MANUAL_FC_0), based on the external PHYs auto-negotiation results.
7.3.3 Virtual PHY Resets
In addition to the chip-level hardware reset (nRST) and Power-On Reset (POR), the Virtual PHY
supports two block specific resets. These are is discussed in the following sections. For detailed
information on all resets, refer to Section 4.2, "Resets," on page 48.
7.3.3.1 Virtual PHY Software Reset via RESET_CTL
The Virtual PHY can be reset via the Reset Control Register (RESET_CTL) by setting the Virtual PHY
Reset (VPHY_RST) bit. This bit is self clearing after approximately 102uS.
7.3.3.2 Virtual PHY Software Reset via VPHY_BASIC_CTRL
The Virtual PHY can also be reset by setting the Reset (VPHY_RST) bit of the Virtual PHY Basic
Control Register (VPHY_BASIC_CTRL). This bit is self clearing and will return to 0 after the reset is
complete.
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Chapter 8 Serial Management
8.1 Functional Overview
This chapter details the serial management functionality provided by the device, which includes the
EEPROM I2C master, EEPROM Loader, and I2C slave controller.
The I2C EEPROM controller is an I2C master module which interfaces an optional external EEPROM
with the system register bus and the EEPROM Loader. Multiple sizes of external EEPROMs are
supported. Configuration of the EEPROM size is accomplished via the eeprom_size_strap
configuration strap. Various commands are supported for EEPROM access, allowing for the storage
and retrieval of static data. The I2C interface conforms to the NXP I2C-Bus Specification.
The EEPROM Loader provides the automatic loading of configuration settings from the EEPROM into
the device at reset. The EEPROM Loader module interfaces to the EEPROM Controller, Ethernet
PHYs, and the system CSRs.
The I2C slave controller can be used for CPU serial management and allow CPU access to all system
CSRs. The I2C slave controller implements the low level I2C slave serial interface (start and stop
condition detection, data bit transmission/reception, and acknowledge generation/reception), handles
the slave command protocol, and performs system register reads and writes. The I2C slave controller
conforms to the NXP I2C-Bus Specification.
8.2 I2C Overview
I2C is a bi-directional 2-wire data protocol. A device that sends data is defined as a transmitter and a
device that receives data is defined as a receiver. The bus is controlled by a master which generates
the EE_SCL clock, controls bus access, and generates the start and stop conditions. Either the master
or slave may operate as a transmitter or receiver as determined by the master.
The device implements an I2C master for accessing an external EEPROM and an I2C slave for control
by a management master. Both the clock and data signals have digital input filters that reject pulses
that are less than 100nS. The I2C Master and the I2C Slave Serial interfaces share common pins. The
data pin is driven low when either interface sends a low, emulating the wired-AND function of the I2C
bus. Since the slave interface never drives the clock pin, the wired-AND is not necessary.
The following bus states exist:
Idle: Both EE_SDA/SDA and EE_SCL/SCL are high when the bus is idle.
Start & Stop Conditions: A start condition is defined as a high to low transition on the EE_ SDA
line while EE_ SCL is high. A stop condition is defined as a low to high transition on the EE_SDA
line while EE_SCL is high. The bus is considered to be busy following a start condition and is
considered free 4.7uS/1.3uS (for 100KHz and 400KHz operation, respectively) following a stop
condition. The bus stays busy following a repeated start condition (instead of a stop condition).
Starts and repeated starts are otherwise functionally equivalent.
Data Valid: Data is valid, following the start condition, when EE_SDA is stable while EE_SCL is
high. Data can only be changed while the clock is low. There is one valid bit per clock pulse. Every
byte must be 8 bits long and is transmitted msb first.
Acknowledge: Each byte of data is followed by an acknowledge bit. The master generates a ninth
clock pulse for the acknowledge bit. The transmitter releases EE_SDA/SDA (high). The receiver
drives EE_SDA/SDA low so that it remains valid during the high period of the clock, taking into
account the setup and hold times. The receiver may be the master or the slave depending on the
direction of the data. Typically the receiver acknowledges each byte. If the master is the receiver,
it does not generate an acknowledge on the last byte of a transfer. This informs the slave to not
drive the next byte of data so that the master may generate a stop or repeated start condition.
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Figure 8.1 displays the various bus states of a typical I2C cycle.
8.3 I2C Master EEPROM Controller
The I2C EEPROM controller supports I2C compatible EEPROMs.
Note: When the EEPROM Loader is running, it has exclusive use of the I2C EEPROM controller.
Refer to Section 8.4, "EEPROM Loader" for more information.
The I2C master implements a low level serial interface (start and stop condition generation, data bit
transmission and reception, acknowledge generation and reception) for connection to I2C EEPROMs,
and consists of a data wire (EE_SDA) and a serial clock (EE_SCL). The serial clock is driven by the
master, while the data wire is bi-directional. Both signals are open-drain and require external pull-
upresistors.
The I2C master interface runs at the standard-mode rate of 100KHz and is fully compliant with the NXP
I2C-Bus Specification. Refer to the he NXP I2C-Bus Specification for detailed timing information.
Based on the eeprom_size_strap configuration strap, various sized I2C EEPROMs are supported. The
varying size ranges are supported by additional bits in the EEPROM Controller Address
(EPC_ADDRESS) field of the EEPROM Command Register (E2P_CMD). Within each size range, the
largest EEPROM uses all the address bits, while the smaller EEPROMs treat the upper address bits
as don’t cares. The EEPROM controller drives all the address bits as requested regardless of the
actual size of the EEPROM. The supported size ranges for I2C operation are shown in Table 8.1.
Note 8.1 Bits in the control byte are used as the upper address bits.
Figure 8.1 I2C Cycle
Table 8.1 I2C EEPROM Size Ranges
eeprom_size_strap # OF ADDRESS BYTES EEPROM SIZE EEPROM TYPES
01 (Note 8.1) 16 x 8 through 2048 x 8 24xx00, 24xx01, 24xx02,
24xx04, 24xx08, 24xx16
1 2 4096 x 8 through 65536 x 8 24xx32, 24xx64, 24xx128,
24xx256, 24xx512
EE_SDA
EE_SCL
S
Start Condition
P
Stop Condition
Data Valid
or Ack
Data Valid
or Ack
data
stable
data
can
change
data
stable
data
can
change
Sr
Re-Start
Condition
data
can
change
data
can
change
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8.3.1 I2C EEPROM Device Addressing
The I2C EEPROM is addressed for a read or write operation by first sending a control byte followed
by the address byte or bytes. The control byte is preceded by a start condition. The control byte and
address byte(s) are each acknowledged by the EEPROM slave. If the EEPROM slave fails to send an
acknowledge, then the sequence is aborted and the EEPROM Controller Timeout (EPC_TIMEOUT) bit
of the EEPROM Command Register (E2P_CMD) is set.
The control byte consists of a 4-bit control code, 3-bits of chip/block select and one direction bit. The
control code is 1010b. For single byte addressing EEPROMs, the chip/block select bits are used for
address bits 10, 9, and 8. For double byte addressing EEPROMs, the chip/block select bits are set
low. The direction bit is set low to indicate the address is being written.
Figure 8.2 illustrates typical I2C EEPROM addressing bit order for single and double byte addressing.
8.3.2 I2C EEPROM Byte Read
Following the device addressing, a data byte may be read from the EEPROM by outputting a start
condition and control byte with a control code of 1010b, chip/block select bits as described in
Section 8.3.1, and the R/~W bit high. The EEPROM will respond with an acknowledge, followed by 8-
bits of data. If the EEPROM slave fails to send an acknowledge, then the sequence is aborted and
the EEPROM Controller Timeout (EPC_TIMEOUT) bit in the EEPROM Command Register
(E2P_CMD) is set. The I2C master then sends a no-acknowledge, followed by a stop condition.
Figure 8.3 illustrates typical I2C EEPROM byte read for single and double byte addressing.
For a register level description of a read operation, refer to Section 8.3.7, "I2C Master EEPROM
Controller Operation," on page 119.
Figure 8.2 I2C EEPROM Addressing
Figure 8.3 I2C EEPROM Byte Read
S 1 0 1 0
A
1
0
A
9
A
80
R/~W
Control Byte
A
7
A
6
A
5
A
4
A
3
A
2
A
1
A
0
A
C
K
A
C
K
Chip / Block
Select Bits
S 1 0 1 0 0
Control Byte
A
C
K
A
C
K
Single Byte Addressing Double Byte Addressing
A
7
A
6
A
5
A
4
A
3
A
2
A
1
A
0
A
C
K
Address Byte
Address Low
Byte
Address High
Byte
A
9
A
8
0 0 0
A
1
5
A
1
4
A
1
3
A
1
2
A
1
1
A
1
0
R/~W
Chip / Block
Select Bits
S 1 0 1 0
A
1
0
A
9
A
8
Control Byte
A
C
K
S 1 0 1 0
Control Byte
A
C
K
Single Byte Addressing Read Double Byte Addressing Read
0 0 01
Data Byte
D
7
D
6
D
5
D
4
D
3
D
2
D
1
D
0
A
C
K
P 1
Data Byte
D
7
D
6
D
5
D
4
D
3
D
2
D
1
D
0
A
C
K
P
A
C
K
A
C
K
R/~W
Chip / Block
Select Bits
R/~W
Chip / Block
Select Bits
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8.3.3 I2C EEPROM Sequential Byte Reads
Following the device addressing, data bytes may be read sequentially from the EEPROM by outputting
a start condition and control byte with a control code of 1010b, chip/block select bits as described in
Section 8.3.1, and the R/~W bit high. The EEPROM will respond with an acknowledge, followed by 8-
bits of data. If the EEPROM slave fails to send an acknowledge, then the sequence is aborted and
the EEPROM Controller Timeout (EPC_TIMEOUT) bit in the EEPROM Command Register
(E2P_CMD) is set. The I2C master then sends an acknowledge, and the EEPROM responds with the
next 8-bits of data. This continues until the last desired byte is read, at which point the I2C master
sends a no-acknowledge, followed by a stop condition.
Figure 8.3 illustrates typical I2C EEPROM sequential byte reads for single and double byte addressing.
Sequential reads are used by the EEPROM Loader. Refer to Section 8.4, "EEPROM Loader" for
additional information.
For a register level description of a read operation, refer to Section 8.3.7, "I2C Master EEPROM
Controller Operation," on page 119.
8.3.4 I2C EEPROM Byte Writes
Following the device addressing, a data byte may be written to the EEPROM by outputting the data
after receiving the acknowledge from the EEPROM. The data byte is acknowledged by the EEPROM
slave and the I2C master finishes the write cycle with a stop condition. If the EEPROM slave fails to
send an acknowledge, then the sequence is aborted and the EEPROM Controller Timeout
(EPC_TIMEOUT) bit in the EEPROM Command Register (E2P_CMD) is set.
Following the data byte write cycle, the I2C master will poll the EEPROM to determine when the byte
write is finished. After meeting the minimum bus free time, a start condition is sent followed by a control
byte with a control code of 1010b, chip/block select bits low, and the R/~W bit low. If the EEPROM is
finished with the byte write, it will respond with an acknowledge. Otherwise, it will respond with a no-
acknowledge and the I2C master will issue a stop and repeat the poll. If the acknowledge does not
occur within 30mS, a time-out occurs. The check for timeout is only performed following each no-
acknowledge, since it may be possible that the EEPROM write finished before the timeout but the
30mS expired before the poll was performed (due to the bus being used by another master).
Once the I2C master receives the acknowledge, it concludes by sending a start condition, followed by
a stop condition, which will place the EEPROM into standby.
Figure 8.4 I2C EEPROM Sequential Byte Reads
S1010
A
1
0
A
9
A
8
Control Byte
A
C
K
S1010
Control Byte
A
C
K
Single Byte Addressing Sequential Reads
000
1
Data Byte
D
7
D
6
D
5
D
4
D
3
D
2
D
1
D
0
A
C
K
P
1
Data Byte
D
7
D
6
D
5
D
4
D
3
D
2
D
1
D
0
A
C
K
A
C
K
A
C
K
Data Byte
D
7
D
6
D
5
D
4
D
3
D
2
D
1
D
0
A
C
K
Data Byte
D
7
D
6
D
5
D
4
D
3
D
2
D
1
D
0
A
C
K
P
A
C
K
Data Byte
D
7
D
6
D
5
D
4
D
3
D
2
D
1
D
0
A
C
K
Data Byte
D
7
D
6
D
5
D
4
D
3
D
2
D
1
D
0
Double Byte Addressing Sequential Reads
...
R/~W
Chip / Block
Select Bits
R/~W
Chip / Block
Select Bits
...
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Figure 8.3 illustrates typical I2C EEPROM byte write.
For a register level description of a write operation, refer to Section 8.3.7, "I2C Master EEPROM
Controller Operation," on page 119.
8.3.5 Wait State Generation
The serial clock is also used as an input as it can be held low by the slave device in order to wait-
state the data cycle. Once the slave has data available or is ready to receive, it will release the clock.
Assuming the masters clock low time is also expired, the clock will rise and the cycle will continue. If
the slave device holds the clock low for more than 30mS, the current command sequence is aborted
and the EEPROM Controller Timeout (EPC_TIMEOUT) bit in the EEPROM Command Register
(E2P_CMD) is set.
8.3.6 I2C Bus Arbitration and Clock Synchronization
Since the I2C Master and the I2C Slave Serial interfaces share common pins, there are at least two
master I2C devices on the bus (the device and the Host). There exists the potential that both masters
try to access the bus at the same time. The I2C specification handles this situation with three
mechanisms: bus busy, clock synchronization and bus arbitration.
Note: The timing parameters referred to in the following subsections refer to the detailed timing
information presented in the NXP I2C-Bus Specification.
8.3.6.1 Bus Busy
A master may start a transfer only if the bus is not busy. The bus is considered to be busy after the
START condition and is considered to be free again tbuf time after the STOP condition. The standard
mode value of 4.7us is used for tbuf since the EEPROM master runs at the standard mode rate.
Following reset, it is unknown if the bus is actually busy, since the START condition may have been
missed. Therefore, following reset, the bus is initially considered busy and is considered free tbuf time
after the STOP condition or if clock and data are seen high for 4mS. In order to speed up device
configuration, if the management mode is not I2C, this check is not performed (the bus is initially
considered free).
8.3.6.2 Clock Synchronization
Clock synchronization is used, since both masters may be generating different clock frequencies.
When the clock is driven low by one master, each other active master will restart its low timer and also
drive the clock low. Each master will drive the clock low for its minimum low time and then release it.
The clock line will not go high until all masters have released it. The slowest master therefore
determines the actual low time. Devices with shorter low timers will wait. Once the clock goes high,
each master will start its high timer. The first master to reach its high time will once again drive the
clock low. The fastest master therefore determines the actual high time. The process then repeats.
Clock synchronization is similar to the cycle stretching that can be done by a slave device, with the
Figure 8.5 I2C EEPROM Byte Write
A
C
K
Data Byte
P
A
C
K
S 1 0 1 0 0
Control Byte
0 0 0 S 1 0 1 0 00 0 0 S 1 0 1 0 00 0 0
...
D
7
D
6
D
5
D
4
D
3
D
2
D
1
D
0
A
C
K
A
C
K
A
C
K
S P
Poll Cycle Poll Cycle Poll CycleData Cycle
Conclude
R/~W
Chip / Block
Select Bits
R/~W
Chip / Block
Select Bits
R/~W
Chip / Block
Select Bits
Control Byte Control Byte
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exception that a slave device can only extend the low time of the clock. It can not cause the falling
edge of the clock.
8.3.6.3 Arbitration
Arbitration involves testing the input data vs. the output data, when the clock goes high, to see if they
match. Since the data line is wired-AND’ed, a master transmitting a high value will see a mismatch if
another master is transmitting a low value. The comparison is not done when receiving bits from the
slave. Arbitration starts with the control byte and, if both masters are accessing the same slave, can
continue into address and data bits (for writes) or acknowledge bits (for reads). If desired, a master
that loses arbitration can continue to generate clock pulses until the end of the loosing byte (note that
the ACK on a read is considered the end of the byte) but the losing master may no longer drive any
data bits. It is not permitted for another master to access the EEPROM while the device is using it
during startup or due to an EEPROM command. The other master should wait sufficient time or poll
the device to determine when the EEPROM is available. This restriction simplifies the arbitration and
access process since arbitration will always be resolved when transmitting the 8 control bits during the
Device Addressing or during the Poll Cycles. If arbitration is lost during the Device Addressing, the I2C
Master will return to the beginning of the Device Addressing sequence and wait for the bus to become
free. If arbitration is lost during a Poll Cycle, the I2C Master will return to the beginning of the Poll
Cycle sequence and wait for the bus to become free. Note that in this case the 30mS time out counter
should not be reset. If the 30mS timeout should expire while waiting for the bus to become free, the
sequence should not abort without first completing a final poll (with the exception of the busy /
arbitration timeout described in Section 8.3.6.4).
8.3.6.4 Timeout Due to Busy or Arbitration
It is possible for another master to monopolize the bus (due to a continual bus busy or more successful
arbitration). If successful arbitration is not achieved within 1.92 seconds from the start of the read or
write request or from the start of the Poll cycle, the command sequence or Poll cycle is aborted and
the EEPROM Controller Timeout (EPC_TIMEOUT) bit in the EEPROM Command Register
(E2P_CMD) is set. Note that this is a total timeout value and not the timeout for any one portion of
the sequence.
8.3.7 I2C Master EEPROM Controller Operation
I2C master EEPROM operations are performed using the EEPROM Command Register (E2P_CMD)
and EEPROM Data Register (E2P_DATA).
The following operations are supported:
READ (Read Location)
WRITE (Write Location)
RELOAD (EEPROM Loader Reload - See Section 8.4, "EEPROM Loader")
Note: The EEPROM Loader uses the READ command only.
The supported commands are detailed in Section 13.2.3.1, "EEPROM Command Register
(E2P_CMD)," on page 160. Details specific to each operational mode are explained in Section 8.2,
"I2C Overview" and Section 8.4, "EEPROM Loader", respectively.
When issuing a WRITE command, the desired data must first be written into the EEPROM Data
Register (E2P_DATA). The WRITE command may then be issued by setting the EEPROM Controller
Command (EPC_COMMAND) field of the EEPROM Command Register (E2P_CMD) to the desired
command value. If the operation is a WRITE, the EEPROM Controller Address (EPC_ADDRESS) field
in the EEPROM Command Register (E2P_CMD) must also be set to the desired location. The
command is executed when the EEPROM Controller Busy (EPC_BUSY) bit of the EEPROM
Command Register (E2P_CMD) is set. The completion of the operation is indicated when the
EEPROM Controller Busy (EPC_BUSY) bit is cleared.
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When issuing a READ command, the EEPROM Controller Command (EPC_COMMAND) and
EEPROM Controller Address (EPC_ADDRESS) fields of the EEPROM Command Register
(E2P_CMD) must be configured with the desired command value and the read address, respectively.
The READ command is executed by setting the EEPROM Controller Busy (EPC_BUSY) bit of the
EEPROM Command Register (E2P_CMD). The completion of the operation is indicated when the
EEPROM Controller Busy (EPC_BUSY) bit is cleared, at which time the data from the EEPROM may
be read from the EEPROM Data Register (E2P_DATA).
The RELOAD operation is performed by writing the RELOAD command into the EEPROM Controller
Command (EPC_COMMAND) field of the EEPROM Command Register (E2P_CMD). The command
is executed by setting the EEPROM Controller Busy (EPC_BUSY) bit of the EEPROM Command
Register (E2P_CMD). In all cases, the software must wait for the EEPROM Controller Busy
(EPC_BUSY) bit to clear before modifying the EEPROM Command Register (E2P_CMD).
If an operation is attempted and the EEPROM device does not respond within 30mS, the device will
time-out, and the EEPROM Controller Timeout (EPC_TIMEOUT) bit of the EEPROM Command
Register (E2P_CMD) will be set.
Figure 8.6 illustrates the process required to perform an EEPROM read or write operation.
Figure 8.6 EEPROM Access Flow Diagram
EEPROM Write
Idle
Write
E2P_DATA
Register
Write
E2P_CMD
Register
Read
E2P_CMD
Register
EPC_BUSY = 0
EEPROM Read
Idle
Write
E2P_CMD
Register
Read
E2P_CMD
Register
Read
E2P_DATA
Register
EPC_BUSY = 0
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8.4 EEPROM Loader
The EEPROM Loader interfaces to the I2C EEPROM controller, the PHYs, and to the system CSRs
(via the Register Access MUX). All system CSRs are accessible to the EEPROM Loader.
The EEPROM Loader runs upon a pin reset (nRST), power-on reset (POR), digital reset (Digital Reset
(DIGITAL_RST) bit in the Reset Control Register (RESET_CTL)), or upon the issuance of a RELOAD
command via the EEPROM Command Register (E2P_CMD). Refer to Section 4.2, "Resets," on
page 48 for additional information on resets.
The EEPROM contents must be loaded in a specific format for use with the EEPROM Loader. An
overview of the EEPROM content format is shown in Ta b l e 8 . 2 . Each section of EEPROM contents is
discussed in detail in the following sections.
8.4.1 EEPROM Loader Operation
Upon a pin reset (nRST), power-on reset (POR), digital reset (Digital Reset (DIGITAL_RST) bit in the
Reset Control Register (RESET_CTL)), or upon the issuance of a RELOAD command via the
EEPROM Command Register (E2P_CMD), the EEPROM Controller Busy (EPC_BUSY) bit in the
EEPROM Command Register (E2P_CMD) will be set. While the EEPROM Loader is active, the Device
Ready (READY) bit of the Hardware Configuration Register (HW_CFG) is cleared and no writes to the
device should be attempted. The operational flow of the EEPROM Loader can be seen in Figure 8.7.
Table 8.2 EEPROM Contents Format Overview
EEPROM ADDRESS DESCRIPTION VALUE
0 EEPROM Valid Flag A5h
1 MAC Address Low Word [7:0] 1st Byte on the Network
2 MAC Address Low Word [15:8] 2nd Byte on the Network
3 MAC Address Low Word [23:16] 3rd Byte on the Network
4 MAC Address Low Word [31:24] 4th Byte on the Network
5 MAC Address High Word [7:0] 5th Byte on the Network
6 MAC Address High Word [15:8] 6th Byte on the Network
7 Configuration Strap Values Valid Flag A5h
8 - 11 Configuration Strap Values See Table 8.3
12 Burst Sequence Valid Flag A5h
13 Number of Bursts See Section 8.4.5, "Register
Data"
14 and above Burst Data See Section 8.4.5, "Register
Data"
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Figure 8.7 EEPROM Loader Flow Diagram
Byte 0 = A5h N
DIGITAL_RST, nRST,
POR, RELOAD
N
Y
EPC_BUSY = 1
Read Byte 0
Read Bytes 1-6
Write Bytes 1-6 into
switch MAC Address
Registers
Read Byte 7-11
Byte 7 = A5h
Y
Write Bytes 8-11 into
Configuration Strap
registers
Update PHY registers
Update VPHY registers
Update registers:
P1_MII_BASIC_CONTROL,
LED_CFG,
MANUAL_FC_1,
MANUAL_FC_2 and
MANUAL_FC_0
Read Byte 12
Byte 12 = A5h
Do register data loop
Y
Load PHY registers with
current straps
Load PHY registers with
current straps
N
EPC_BUSY = 0
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8.4.2 EEPROM Valid Flag
Following the release of nRST, POR, DIGITAL_RST, or a RELOAD command, the EEPROM Loader
starts by reading the first byte of data from the EEPROM. If the value of A5h is not read from the first
byte, the EEPROM Loader will load the current configuration strap values into the PHY registers (see
Section 8.4.4.1) and then terminate, clearing the EEPROM Controller Busy (EPC_BUSY) bit in the
EEPROM Command Register (E2P_CMD). Otherwise, the EEPROM Loader will continue reading
sequential bytes from the EEPROM.
8.4.3 MAC Address
The next six bytes in the EEPROM, after the EEPROM Valid Flag, are written into the Switch Fabric
MAC Address High Register (SWITCH_MAC_ADDRH) and Switch Fabric MAC Address Low Register
(SWITCH_MAC_ADDRL). The EEPROM bytes are written into the MAC address registers in the order
specified in Table 8.2.
8.4.4 Soft-Straps
The 7th byte of data to be read from the EEPROM is the Configuration Strap Values Valid Flag. If this
byte has a value of A5h, the next 4 bytes of data (8-11) are written into the configuration strap registers
per the assignments detailed in Table 8.3. If the flag byte is not A5h, these next 4 bytes are skipped
(they are still read to maintain the data burst, but are discarded). However, the current configuration
strap values are still loaded into the PHY registers (see Section 8.4.4.1). Refer to Section 4.2.4,
"Configuration Straps," on page 52 for more information on configuration straps.
8.4.4.1 PHY Registers Synchronization
Some PHY register defaults are based on configuration straps. In order to maintain consistency
between the updated configuration strap registers and the PHY registers, the Port x PHY Auto-
Negotiation Advertisement Register (PHY_AN_ADV_x), Port x PHY Special Modes Register
(PHY_SPECIAL_MODES_x), and Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x) are
written when the EEPROM Loader is run.
The Port x PHY Auto-Negotiation Advertisement Register (PHY_AN_ADV_x) is written with the new
defaults as detailed in Section 13.3.2.5, "Port x PHY Auto-Negotiation Advertisement Register
(PHY_AN_ADV_x)," on page 214.
The Port x PHY Special Modes Register (PHY_SPECIAL_MODES_x) is written with the new defaults
as detailed in Section 13.3.2.9, "Port x PHY Special Modes Register (PHY_SPECIAL_MODES_x)," on
page 221.
Table 8.3 EEPROM Configuration Bits
BYTE/BIT765 4 321 0
Byte 8 BP_EN_
strap_1
FD_FC_
strap_1
manual_
FC_strap_1
manual_mdix
_strap_1
auto_mdix_
strap_1
speed_
strap_1
duplex_
strap_1 /
duplex_pol_
strap_1
autoneg_
strap_1/
SQE_test_
disable_strap
_1
Byte 9 BP_EN_
strap_2
FD_FC_
strap_2
manual_
FC_strap_2
manual_mdix
_strap_2
auto_mdix_
strap_2
speed_
strap_2
duplex_
strap_2
autoneg_
strap_2
Byte 10 unused BP_EN_
strap_0
FD_FC_
strap_0
manual_FC
_strap_0
speed_
strap_0
duplex_pol_
strap_0
SQE_test_
disable_strap
_0
Byte 11 LED_fun_strap[1:0] LED_en_strap[5:0]
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The Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x) is written with the new defaults
as detailed in Section 13.3.2.1, "Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x)," on
page 208. Additionally, the Restart Auto-Negotiation (PHY_RST_AN) bit is set in these registers. This
re-runs the Auto-negotiation using the new default values of the Port x PHY Auto-Negotiation
Advertisement Register (PHY_AN_ADV_x) register to determine the new Auto-negotiation results.
Note: Each of these PHY registers is written in its entirety, overwriting any previously changed bits.
Note: When any external MII mode is selected, the PHY registers for Port 1 are not updated.
Following the writes to the PHY registers, the PMI registers are reset back to their default values.
8.4.4.2 Virtual PHY Registers Synchronization
Some PHY register defaults are based on configuration straps. In order to maintain consistency
between the updated configuration strap registers and the Virtual PHY registers, the Virtual PHY Auto-
Negotiation Advertisement Register (VPHY_AN_ADV), Virtual PHY Special Control/Status Register
(VPHY_SPECIAL_CONTROL_STATUS), and Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL) are written when the EEPROM Loader is run.
The Virtual PHY Auto-Negotiation Advertisement Register (VPHY_AN_ADV) is written with the new
defaults as detailed in Section 13.2.6.5, "Virtual PHY Auto-Negotiation Advertisement Register
(VPHY_AN_ADV)," on page 188.
The Virtual PHY Special Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS) is written
with the new defaults as detailed in Section 13.2.6.8, "Virtual PHY Special Control/Status Register
(VPHY_SPECIAL_CONTROL_STATUS)," on page 194.
The Virtual PHY Basic Control Register (VPHY_BASIC_CTRL) is written with the new defaults as
detailed in Section 13.2.6.1, "Virtual PHY Basic Control Register (VPHY_BASIC_CTRL)," on page 182.
Additionally, the Restart Auto-Negotiation (PHY_RST_AN) bit is set in this register. This re-runs the
Auto-negotiation using the new default values of the Virtual PHY Auto-Negotiation Advertisement
Register (VPHY_AN_ADV) register to determine the new Auto-negotiation results.
Note: Each of these VPHY registers is written in its entirety, overwriting any previously changed bits.
8.4.4.3 Port 1 MII Basic Control Register Synchronization
Some of the defaults of the Port 1 MII Basic Control Register are based on configuration straps. In
order to maintain consistency between the updated Configuration Strap registers and the register, it is
written with the new defaults as detailed in Section 13.2.7.7, "Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL)," on page 202.
Note: The register is written in its entirety, overwriting any previously changed bits.
8.4.4.4 LED and Manual Flow Control Register Synchronization
Since the defaults of the LED Configuration Register (LED_CFG), Port 1 Manual Flow Control Register
(MANUAL_FC_1), Port 2 Manual Flow Control Register (MANUAL_FC_2), and Port 0 Manual Flow
Control Register (MANUAL_FC_0) are based on configuration straps, the EEPROM Loader reloads
these registers with their new default values.
8.4.5 Register Data
Optionally following the configuration strap values, the EEPROM data may be formatted to allow
access to the device’s parallel, directly writable registers. Access to indirectly accessible registers (e.g.
Switch Engine registers, etc.) is achievable with an appropriate sequence of writes (at the cost of
EEPROM space).
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This data is first preceded with a Burst Sequence Valid Flag (EEPROM byte 12). If this byte has a
value of A5h, the data that follows is recognized as a sequence of bursts. Otherwise, the EEPROM
Loader is finished, will go into a wait state, and clear the EEPROM Controller Busy (EPC_BUSY) bit
in the EEPROM Command Register (E2P_CMD). This can optionally generate an interrupt.
The data at EEPROM byte 13 and above should be formatted in a sequence of bursts. The first byte
is the total number of bursts. Following this is a series of bursts, each consisting of a starting address,
count, and the count x 4 bytes of data. This results in the following formula for formatting register data:
8-bits number_of_bursts
repeat (number_of_bursts)
16-bits {starting_address[9:2] / count[7:0]}
repeat (count)
8-bits data[31:24], 8-bits data[23:16], 8-bits data[15:8], 8-bits data[7:0]
Note: The starting address is a DWORD address. Appending two 0 bits will form the register address.
As an example, the following is a 3 burst sequence, with 1, 2, and 3 DWORDs starting at register
addresses 40h, 80h, and C0h respectively:
A5h, (Burst Sequence Valid Flag)
3h, (number_of_bursts)
16{10h, 1h}, (starting_address1 divided by 4 / count1)
11h, 12h, 13h, 14h, (4 x count1 of data)
16{20h, 2h}, (starting_address2 divided by 4 / count2)
21h, 22h, 23h, 24h, 25h, 26h, 27h, 28h, (4 x count2 of data)
16{30h, 3h}, (starting_address3 divided by 4 / count3)
31h, 32h, 33h, 34h, 35h, 36h, 37h, 38h, 39h, 3Ah, 3Bh, 3Ch (4 x count3 of data)
In order to avoid overwriting the Switch CSR register interface or the PHY Management Interface
(PMI), the EEPROM Loader waits until the CSR Busy (CSR_BUSY) bit of the Switch Fabric CSR
Interface Command Register (SWITCH_CSR_CMD) and the MII Busy (MIIBZY) bit of the PHY
Management Interface Access Register (PMI_ACCESS) are cleared before performing any register
write.
The EEPROM Loader checks that the EEPROM address space is not exceeded. If so, it will stop and
set the EEPROM Loader Address Overflow (LOADER_OVERFLOW) bit in the EEPROM Command
Register (E2P_CMD). The address limit is based on the eeprom_size_strap which specifies a range
of sizes. The address limit is set to the largest value of the specified range.
8.4.6 EEPROM Loader Finished Wait-State
Once finished with the last burst, the EEPROM Loader will go into a wait-state and the EEPROM
Controller Busy (EPC_BUSY) bit of the EEPROM Command Register (E2P_CMD) will be cleared.
8.4.7 Reset Sequence and EEPROM Loader
In order to allow the EEPROM Loader to change the Port 1/2 PHYs and Virtual PHY strap inputs and
maintain consistency with the PHY and Virtual PHY registers, the following sequence is used:
1. After power-up or upon a hardware reset (nRST), the straps are sampled into the device as
specified in Section 14.5.2, "Reset and Configuration Strap Timing," on page 368.
2. After the PLL is stable, the main chip reset is released and the EEPROM Loader reads the
EEPROM and configures (overrides) the strap inputs.
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3. The EEPROM Loader writes select Port 1/2 and Virtual PHY registers, as specified in
Section 8.4.4.1 and Section 8.4.4.2, respectively.
Note: Step 3 is also performed in the case of a RELOAD command or digital reset.
8.5 I2C Slave Operation
When in MAC/PHY I2C managed mode, the I2C slave interface is used for CPU management of the
device. All system CSRs are accessible to the CPU in these modes. I2C mode is selected when the
mngt_mode_strap[1:0] configuration straps are set to 10b, respectively. The I2C slave controller
implements the low level I2C slave serial interface (start and stop condition detection, data bit
transmission and reception, and acknowledge generation and reception), handles the slave command
protocol, and performs system register reads and writes. The I2C slave controller conforms to the NXP
I2C-Bus Specification.
The I2C slave serial interface consists of a data wire (SDA) and a serial clock (SCL). The serial clock
is driven by the master, while the data wire is bi-directional. Both signals are open-drain and require
external pull-up resistors.
The I2C slave serial interface supports the standard-mode speed of up to 100KHz and the fast-mode
speed of 400KHz. Refer to the NXP I2C-Bus Specification for detailed I2C timing information.
8.5.1 I2C Slave Command Format
The I2C slave serial interface supports single register and multiple register read and write commands.
A read or write command is started by the master first sending a start condition, followed by a control
byte. The control byte consists of a 7-bit slave address and a 1-bit read/write indication (R/~W). The
slave address used by the device is 0001010b, written as SA6 (first bit on the wire) through SA0 (last
bit on the wire). Assuming the slave address in the control byte matches this address, the control byte
is acknowledged by the device. Otherwise, the entire sequence is ignored until the next start condition.
The I2C command format can be seen in Figure 8.8.
If the read/write indication (R/~W) in the control byte is a 0 (indicating a potential write), the next byte
sent by the master is the register address. After the address byte is acknowledged by the device, the
master may either send data bytes to be written, or it may send another start condition (to start the
reading of data), or a stop condition. The latter two will terminate the current write (without writing any
data), but will have the affect of setting the internal register address which will be used for subsequent
reads.
If the read/write indication in the control byte is a 1 (indicating a read), the device will start sending
data following the control byte acknowledgement.
Note: All registers are accessed as DWORDs. Appending two 0 bits to the address field will form the
register address. Addresses and data are transferred msb first. Data is transferred MSB first
(little endian).
Figure 8.8 I2C Slave Addressing
S
S
A
2
S
A
1
S
A
0
0
R/~W
Control Byte
A
7
A
6
A
5
A
4
A
3
A
2
A
C
K
A
C
K
Address Byte
S
A
6
S
A
5
S
A
4
S
A
3
*
Start or
Stop or
Data [31]
A
9
A
8
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8.5.2 I2C Slave Read Sequence
Following the device addressing, as detailed in Section 8.5.1, a register is read from the device when
the master sends a start condition and control byte with the R/~W bit set. Assuming the slave address
in the control byte matches the device address, the control byte is acknowledged by the device.
Otherwise, the entire sequence is ignored until the next start condition. Following the acknowledge,
the device sends 4 bytes of data. The first 3 bytes are acknowledged by the master and on the fourth,
the master sends a no-acknowledge followed by the stop condition. The no-acknowledge informs the
device not to send the next 4 bytes (as it would in the case of a multiple read). The internal register
address is unchanged following the single read.
Multiple reads are performed when the master sends an acknowledge on the fourth byte. The internal
address is incremented and the next register is shifted out. Once the internal address reaches its
maximum, it rolls over to 0. The multiple read is concluded when the master sends a no-acknowledge
followed by a stop condition. The no-acknowledge informs the device not to send the next 4 bytes.
The internal register address in incremented for each read including the final.
For both single and multiple reads, in the case that the master sends a no-acknowledge on any of the
first three bytes of the register, the device will stop sending subsequent bytes. If the master sends an
unexpected start or stop condition, the device will stop sending immediately and will respond to the
next sequence as needed.
Since data is read serially, register values are latched (registered) at the beginning of each 32-bit read
to prevent the host from reading an intermediate value. The latching occurs multiple times in a multiple
read sequence. In addition, any register that is affected by a read operation (e.g. a clear on read bit)
is not cleared until after all 32-bits are output. In the event that 32-bits are not read (master sends a
no-acknowledge on one of the first three bytes or a start or stop condition occurs unexpectedly), the
read is considered invalid and the register is not affected. Multiple registers may be cleared in a
multiple read cycle, each one being cleared as it is read. I2C reads from unused register addresses
return all zeros.
Figure 8.9 illustrates a typical single and multiple register read.
8.5.2.1 I2C Slave Read Polling for Reset Complete
During reset, the I2C slave interface will not return valid data. To determine when the reset condition
is complete, the Byte Order Test Register (BYTE_TEST) should be polled. Once the correct pattern is
read, the interface can be considered functional. At this point, the Device Ready (READY) bit in the
Hardware Configuration Register (HW_CFG) can be polled to determine when the device initialization
is complete. Refer to Section 4.2, "Resets," on page 48 for additional information.
Figure 8.9 I2C Slave Reads
Multiple Register Reads
S
Control Byte
A
C
K
Single Register Read
1D
5
D
4
D
3
D
2
D
1
D
0
A
C
K
P
S
A
2
S
A
1
S
A
0
S
A
6
S
A
5
S
A
4
S
A
3
A
C
K
D
3
1
D
3
0
D
2
9
D
2
8
S
2
7
D
2
6
D
2
5
D
2
4
D
2
3
D
2
2
S
A
C
K
1
S
A
2
S
A
1
S
A
0
S
A
6
S
A
5
S
A
4
S
A
3
A
C
K
D
3
1
D
3
0
D
2
5
D
2
4
Data Byte...
D
2
1
D
2
0
Data Byte
Data 1 Byte
D
4
D
3
D
2
D
1
D
0
A
C
K
P
D
4
D
3
D
2
D
1
D
0
A
C
K
D
3
1
D
3
0
D
2
9
D
2
8
D
2
7
D
2
6
S
S
A
2
S
A
1
S
A
0
0A
7
A
6
A
5
A
4
A
3
A
2
A
C
K
A
C
K
Address Byte
S
A
6
S
A
5
S
A
4
S
A
3
A
9
A
8
S
S
A
2
S
A
1
S
A
0
0
Control Byte
A
7
A
6
A
5
A
4
A
3
A
2
A
C
K
A
C
K
Address Byte
S
A
6
S
A
5
S
A
4
S
A
3
A
9
A
8
R/~W
R/~W
...
.........
Control Byte Control Byte
...Data Byte
...Data m Byte Data m+1 Byte... ...Data n Byte
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8.5.3 I2C Slave Write Sequence
Following the device addressing, as detailed in Section 8.5.1, a register is written to the device when
the master continues to send data bytes. Each byte is acknowledged by the device. Following the
fourth byte of the sequence, the master may either send another start condition or halt the sequence
with a stop condition. The internal register address is unchanged following a single write.
Multiple writes are performed when the master sends additional bytes following the fourth
acknowledge. The internal address is automatically incremented and the next register is written. once
the internal address reaches it maximum value, it rolls over to 0. The multiple write is concluded when
the master sends another start condition or stop condition. The internal register address is incremented
for each write including the final. This is not relevant for subsequent writes, since a new register
address would be included on a new write cycle. However, this does affect the internal register address
if it were to be used for reads without first resetting the register address.
For both single and multiple writes, if the master sends an unexpected start or stop condition, the
device will stop immediately and will respond to the next sequence as needed.
The data write to the register occurs after the 32-bits are input. In the event that 32-bits are not written
(master sends a start, or a stop condition occurs unexpectedly), the write is considered invalid and the
register is not affected. Multiple registers may be written in a multiple write cycle, each one being
written after 32-bits. I2C writes must not be performed to unused register addresses.
Figure 8.10 illustrates a typical single and multiple register write.
Figure 8.10 I2C Slave Writes
Multiple Register Writes
Single Register Write
A
C
K
D
5
D
4
D
3
D
2
D
1
D
0P
D
3
1
D
3
0
D
2
9
D
2
8
S
2
7
D
2
6
D
2
5
D
2
4
D
2
3
D
2
2
D
2
1
D
2
0
Data Byte
A
C
K
A
C
K
A
C
K
D
3
1
D
3
0
D
2
5
D
2
4
D
5
D
4
D
3
D
2
D
1
D
0P
D
5
D
4
D
3
D
2
D
1
D
0
A
C
K
D
3
1
D
3
0
D
2
9
D
2
8
D
2
7
D
2
6
D
2
5
A
C
K
A
C
K
S
S
A
2
S
A
1
S
A
0
0A
7
A
6
A
5
A
4
A
3
A
2
A
C
K
Address Byte
S
A
6
S
A
5
S
A
4
S
A
3
A
9
A
8
S
S
A
2
S
A
1
S
A
0
0A
7
A
6
A
5
A
4
A
3
A
2
A
C
K
Address Byte
S
A
6
S
A
5
S
A
4
S
A
3
A
9
A
8
Control Byte
Control Byte Data 1 Byte
.........Data m Byte Data m+1 Byte... ......Data n Byte
......Data Byte
Data Byte...
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Chapter 9 MII Data Interfaces
9.1 Port 0 MII Data Path
The MII Data Path is used to connect the Switch Engine port to the external MII pins, to emulate an
RMII/MII PHY, and to select between PHY and MAC modes.
9.1.1 Port 0 MII MAC Mode
When operating in MII MAC mode, the Switch Fabric MAC output signals are routed directly to the
device’s MII output pins (P0_OUTD[3:0] and P0_OUTDV). The Switch Fabric MAC inputs are sourced
from the MII input pins (P0_IND[3:0], P0_INDV, P0_INER, P0_COL, P0_CRS, P0_OUTCLK, and
P0_INCLK). MII MAC mode can operate at up to 200Mbps.
9.1.2 Port 0 MII PHY Mode
When operating in MII PHY mode, the MII Data Path supplies the RX and TX clocks, creates the CRS
and COL signals and optionally loops back the MII or Switch Engine’s transmissions. It also provides
the collision test function for the external MII pins or Switch Engine. MII PHY mode can operate at up
to 200Mbps (Turbo mode).
The MII pins P0_INCLK, P0_OUTCLK, P0_COL, and P0_CRS, which are inputs when in MII MAC
mode, are outputs when in MII PHY mode. When in MII PHY mode, if the Isolate (VPHY_ISO) bit of
the Virtual PHY Basic Control Register (VPHY_BASIC_CTRL) is set, MII data path output pins are
three-stated, the pull-ups and pull-downs are disabled and the MII data path input pins are ignored
(disabled into the non-active state and powered down). Note that setting the Isolate (VPHY_ISO) bit
does not cause isolation of the MII management pins and does not affect MII MAC mode.
9.1.2.1 Turbo Operation
Turbo (200Mbps) operation is facilitated in MII PHY mode via the Turbo MII Enable bit of the Virtual
PHY Special Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS). When set, this bit
changes the data rate of the MII PHY from 100Mbps to 200Mbps. The Speed Select LSB
(VPHY_SPEED_SEL_LSB) bit of the Virtual PHY Basic Control Register (VPHY_BASIC_CTRL)
toggles between 10 and 200 Mbps operation when Turbo MII Enable is set.
9.1.2.2 Clock Drive Strength
When operating at 200Mbps (Turbo mode), the drive strength of P0_INCLK and P0_OUTCLK pins is
selected based on the setting of the RMII/Turbo MII Clock Strength bit of the Virtual PHY Special
Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS). A low selects 12ma, a high selects
16ma. When operating at 10 or 100Mbps, the drive strength is fixed at 12ma.
9.1.2.3 Signal Quality Error (SQE) Heartbeat Test
The SQE_HEARTBEAT signal, observable on the P0_COL pin, is generated in 10Mbit half duplex
mode in response to a transmission from the external MAC. At 0.6uS to 1.6uS (1.0uS nominal)
following the de-assertion of P0_INDV, SQE_HEARTBEAT is set active for 0.5uS to 1.5uS (5 to 15 bit
times) (1.0uS nominal). This test is disabled via the SQEOFF bit of the Virtual PHY Special
Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS).
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9.1.2.4 Collision Test
Two forms of collision testing are available: External MAC collision testing and Switch Engine collision
testing.
External MAC collision testing is enabled when the Collision Test (VPHY_COL_TEST) bit of the Virtual
PHY Basic Control Register (VPHY_BASIC_CTRL) is set. In this test mode, any transmissions from
the external MAC will result in collision signaling to the external MAC via the P0_COL pin.
Switch Engine collision testing is enabled when the Switch Collision Test Port 0 bit of the Virtual PHY
Special Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS) is set. In this test mode, any
transmissions from the Switch Engine will result in the assertion of the internal collision signal to the
Switch Fabric Port 0. Switch Engine collision testing occurs regardless of the setting of the Isolate
(VPHY_ISO) bit.
9.1.2.5 Loopback
Two forms of loopback testing are available: External MAC loopback and Switch Engine loopback.
External MAC loopback is enabled when the Loopback (VPHY_LOOPBACK) bit of the Virtual PHY
Basic Control Register (VPHY_BASIC_CTRL) is set. Transmissions from the external MAC are not
sent to the Switch Engine and are not used for purposes of signaling data valid, collision or carrier
sense to the Switch Engine. Instead, they are looped back onto the receive path. Transmissions from
the Switch Engine are ignored and are not used for purposes of signaling data valid, collision or carrier
sense on the MII pins. The collision output to the external MAC (via P0_COL) is not generated unless
the Collision Test (VPHY_COL_TEST) bit is set. The SQE_HEARTBEAT signal does not drive the
collision output (via P0_COL) during External MAC loopback but can drive it during Switch Engine
loopback. The carrier sense output on the P0_CRS pin is only based on the transmit enable from the
external MAC (via the P0_INDV pin).
Switch Engine loopback is enabled when the Switch Looopback Port 0 bit of the Virtual PHY Special
Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS) is set. Transmissions from the Switch
Engine are not sent to the external MAC and are not used for purposes of signaling data valid, collision
or carrier sense to the MII pins. Instead, they are looped back internally onto the receive path.
Transmissions from the external MAC are ignored and are not used for purposes of data valid, collision
or carrier sense to the Switch Engine. The collision signal to the Switch Engine is not generated unless
the Switch Collision Test Port 0 bit is set. The carrier sense signal is only based on the transmit enable
from the Switch Engine. Switch Engine loopback occurs regardless of the setting of the Isolate
(VPHY_ISO) bit.
9.1.3 Port 0 RMII PHY Mode
Port 0 RMII PHY mode is used when interfacing Port 0 to an external MAC that does not support the
full MII interface. The RMII interface uses a subset of the MII pins. The P0_OUTD[1:0], P0_OUTDV,
P0_IND[1:0], P0_INDV, and P0_OUTCLK pins are the only MII pins used to communicate with the
external MAC in this mode. This mode provides collision testing for the Switch Engine, as well as
loopback test capabilities.
Note: The RMII standard does not support external MAC collision testing.
When in RMII PHY mode, if the Isolate (VPHY_ISO) bit of the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL) is set, MII data path output pins are three-stated, the pull-ups and pull-downs
are disabled and the MII data path input pins are ignored (disabled into the non-active state and
powered down). Note that setting the Isolate (VPHY_ISO) bit does not cause isolation of the MII
management pins and does not affect MII MAC mode.
9.1.3.1 Reference Clock Selection
The 50MHz RMII reference clock can be selected from either the P0_OUTCLK pin input or the internal
50MHz clock. The choice is based on the setting of the RMII Clock Direction bit of the Virtual PHY
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Special Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS). A low selects P0_OUTCLK
and a high selects the internal 50MHz clock. The high setting also enables P0_OUTCLK as an output
to be used as the system reference clock.
9.1.3.2 Clock Drive Strength
When P0_OUTCLK is configured as an output via the RMII Clock Direction bit of the Virtual PHY
Special Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS), its drive strength is based on
the setting of the RMII/Turbo MII Clock Strength bit of the Virtual PHY Special Control/Status Register
(VPHY_SPECIAL_CONTROL_STATUS). A low selects 12ma, a high selects 16ma.
9.1.3.3 Signal Quality Error (SQE) Heartbeat Test
The SQE_HEARTBEAT signal is not generated when operating in RMII PHY mode. The SQEOFF bit
of the Virtual PHY Special Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS) has no
effect when operating in RMII PHY mode.
9.1.3.4 Collision Test
External MAC collision testing is not available when operating in the RMII PHY mode. The Collision
Test (VPHY_COL_TEST) bit of the Virtual PHY Basic Control Register (VPHY_BASIC_CTRL) has no
effect on system operation in RMII PHY mode.
Switch Engine collision testing is available and is enabled when the Switch Collision Test Port 0 bit of
the Virtual PHY Special Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS) is set. In this
test mode, any transmissions from the Switch Engine will result in the assertion of an internal collision
signal to the Switch Fabric Port 0. Switch Engine collision test occurs regardless of the setting of the
Isolate (VPHY_ISO) bit.
9.1.3.5 Loopback Mode
Two forms of loopback testing are available: External MAC loopback and Switch Engine loopback.
External MAC loopback is enabled when the Loopback (VPHY_LOOPBACK) bit of the Virtual PHY
Basic Control Register (VPHY_BASIC_CTRL) is set. Transmissions from the external MAC are not
sent to the Switch Engine. Instead, they are looped back onto the receive path. Transmissions from
the Switch Engine are ignored.
Switch Engine loopback is enabled when the Switch Looopback Port 0 bit of the Virtual PHY Special
Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS) is set. Transmissions from the Switch
Engine are not sent to the external MAC. Instead, they are looped back internally onto the receive
path. Transmissions from the external MAC are ignored. An internal collision signal to the Switch
Engine is available and is asserted when the Switch Collision Test Port 0 bit is set. Switch Engine
loopback occurs regardless of the setting of the Isolate (VPHY_ISO) bit.
9.2 Port 1 MII MUX/Data Path
The MII MUX/Data Path is used to connect the Switch Engine port to the external MII pins, to emulate
an RMII/MII PHY, and to select between PHY and MAC modes.
9.2.1 Port 1 Internal Mode
When operating in Internal mode, the Switch Fabric MAC outputs are directly connected to the internal
PHY. Similarly, the Switch Fabric Mac inputs are sourced from the internal PHY.
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9.2.2 Port 1 MII MAC Mode
When operating in MII MAC mode, the Switch Fabric MAC output signals are routed directly to the
device’s MII output pins (P1_OUTD[3:0] and P1_OUTDV). The Switch Fabric MAC inputs are sourced
from the MII input pins (P1_IND[3:0], P1_INDV, P1_INER, P1_COL, P1_CRS, P1_OUTCLK, and
P1_INCLK). MII MAC mode can operate at up to 200Mbps.
9.2.3 Port 1 MII PHY Mode
When operating in MII PHY mode, the MII Data Path supplies the RX and TX clocks, creates the CRS
and COL signals and optionally loops back the MII or Switch Engine’s transmissions. It also provides
the collision test function for the external MII pins or Switch Engine. MII PHY mode can operate at up
to 200Mbps (Turbo mode).
The MII pins P1_INCLK, P1_OUTCLK, P1_COL, and P1_CRS, which are inputs when in MII MAC
mode, are outputs when in MII PHY mode. When in MII PHY mode, if the Isolate bit of the Port 1 MII
Basic Control Register (P1_MII_BASIC_CONTROL) is set, MII data path output pins are three-stated,
the pull-ups and pull-downs are disabled and the MII data path input pins are ignored (disabled into
the non-active state and powered down). Note that setting the Isolate bit does not cause isolation of
the MII management pins and does not affect MII MAC mode.
9.2.3.1 Turbo Operation
Turbo (200Mbps) operation is facilitated in MII PHY mode via the Turbo MII Enable bit of the Port 1
MII Basic Control Register (P1_MII_BASIC_CONTROL). When set, this bit changes the data rate of
the MII PHY from 100Mbps to 200Mbps. The Speed Select LSB bit of the Port 1 MII Basic Control
Register (P1_MII_BASIC_CONTROL) toggles between 10 and 200 Mbps operation when Turbo MII
Enable is set.
9.2.3.2 Clock Drive Strength
When operating at 200Mbps (Turbo mode), the drive strength of P1_INCLK and P1_OUTCLK pins is
selected based on the setting of the RMII/Turbo MII Clock Strength bit of the Port 1 MII Basic Control
Register (P1_MII_BASIC_CONTROL). A low selects 12ma, a high selects 16ma. When operating at
10 or 100Mbps, the drive strength is fixed at 12ma.
9.2.3.3 Signal Quality Error (SQE) Heartbeat Test
The SQE_HEARTBEAT signal, observable on the P1_COL pin, is generated in 10Mbit half duplex
mode in response to a transmission from the external MAC. At 0.6uS to 1.6uS (1.0uS nominal)
following the de-assertion of P1_INDV, SQE_HEARTBEAT is set active for 0.5uS to 1.5uS (5 to 15 bit
times) (1.0uS nominal). This test is disabled via the SQEOFF bit of the Port 1 MII Basic Control
Register (P1_MII_BASIC_CONTROL).
9.2.3.4 Collision Test
Two forms of collision testing are available: External MAC collision testing and Switch Engine collision
testing.
External MAC collision testing is enabled when the Collision Test bit of the Port 1 MII Basic Control
Register (P1_MII_BASIC_CONTROL) is set. In this test mode, any transmissions from the external
MAC will result in collision signaling to the external MAC via the P1_COL pin.
Switch Engine collision testing is enabled when the Switch Collision Test Port 1 bit of the Port 1 MII
Basic Control Register (P1_MII_BASIC_CONTROL) is set. In this test mode, any transmissions from
the Switch Engine will result in the assertion of the internal collision signal to the Switch Fabric Port
1. Switch Engine collision testing occurs regardless of the setting of the Isolate bit.
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9.2.3.5 Loopback
Two forms of loopback testing are available: External MAC loopback and Switch Engine loopback.
External MAC loopback is enabled when the Loopback bit of the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL) is set. Transmissions from the external MAC are not sent to the Switch
Engine and are not used for purposes of signaling data valid, collision or carrier sense to the Switch
Engine. Instead, they are looped back onto the receive path. Transmissions from the Switch Engine
are ignored and are not used for purposes of signaling data valid, collision or carrier sense on the MII
pins. The collision output to the external MAC (via P1_COL) is not generated unless the Collision Test
bit is set. The SQE_HEARTBEAT signal does not drive the collision output (via P1_COL) during
External MAC loopback but can drive it during Switch Engine loopback. The carrier sense output on
the P1_CRS pin is only based on the transmit enable from the external MAC (via the P1_INDV pin).
Switch Engine loopback is enabled when the Switch Looopback Port 1 bit of the Port 1 MII Basic
Control Register (P1_MII_BASIC_CONTROL) is set. Transmissions from the Switch Engine are not
sent to the external MAC and are not used for purposes of signaling data valid, collision or carrier
sense to the MII pins. Instead, they are looped back internally onto the receive path. Transmissions
from the external MAC are ignored and are not used for purposes of data valid, collision or carrier
sense to the Switch Engine. The collision signal to the Switch Engine is not generated unless the
Switch Collision Test Port 1 bit is set. The carrier sense signal is only based on the transmit enable
from the Switch Engine. Switch Engine loopback occurs regardless of the setting of the Isolate bit.
9.2.4 Port 1 RMII PHY Mode
Port 1 RMII PHY mode is used when interfacing Port 1 to an external MAC that does not support the
full MII interface. The RMII interface uses a subset of the MII pins. The P1_OUTD[1:0], P1_OUTDV,
P1_IND[1:0], P1_INDV, and P1_OUTCLK pins are the only MII pins used to communicate with the
external MAC in this mode. This mode provides collision testing for the Switch Engine, as well as
loopback test capabilities.
Note: The RMII standard does not support external MAC collision testing.
When in RMII PHY mode, if the Isolate bit of the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL) is set, MII data path output pins are three-stated, the pull-ups and pull-
downs are disabled and the MII data path input pins are ignored (disabled into the non-active state
and powered down). Note that setting the Isolate bit does not cause isolation of the MII management
pins and does not affect MII MAC mode.
9.2.4.1 Reference Clock Selection
The 50MHz RMII reference clock can be selected from either the P1_OUTCLK pin input or the internal
50MHz clock. The choice is based on the setting of the RMII Clock Direction bit of the Port 1 MII Basic
Control Register (P1_MII_BASIC_CONTROL). A low selects P1_OUTCLK and a high selects the
internal 50MHz clock. The high setting also enables P1_OUTCLK as an output to be used as the
system reference clock.
9.2.4.2 Clock Drive Strength
When P1_OUTCLK is configured as an output via the RMII Clock Direction bit of the Port 1 MII Basic
Control Register (P1_MII_BASIC_CONTROL), its drive strength is based on the setting of the
RMII/Turbo MII Clock Strength bit of the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL). A low selects 12ma, a high selects 16ma.
9.2.4.3 Signal Quality Error (SQE) Heartbeat Test
The SQE_HEARTBEAT signal is not generated when operating in RMII PHY mode. The SQEOFF bit
of the Port 1 MII Basic Control Register (P1_MII_BASIC_CONTROL) has no effect when operating in
RMII PHY mode.
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9.2.4.4 Collision Test
External MAC collision testing is not available when operating in the RMII PHY mode. The Collision
Test bit of the Port 1 MII Basic Control Register (P1_MII_BASIC_CONTROL) has no effect on system
operation in RMII PHY mode.
Switch Engine collision testing is available and is enabled when the Switch Collision Test Port 1 bit of
the Port 1 MII Basic Control Register (P1_MII_BASIC_CONTROL) is set. In this test mode, any
transmissions from the Switch Engine will result in the assertion of an internal collision signal to the
Switch Fabric Port 1. Switch Engine collision test occurs regardless of the setting of the Isolate bit.
9.2.4.5 Loopback Mode
Two forms of loopback testing are available: External MAC loopback and Switch Engine loopback.
External MAC loopback is enabled when the Loopback bit of the Port 1 MII Basic Control Register
(P1_MII_BASIC_CONTROL) is set. Transmissions from the external MAC are not sent to the Switch
Engine. Instead, they are looped back onto the receive path. Transmissions from the Switch Engine
are ignored.
Switch Engine loopback is enabled when the Switch Looopback Port 1 bit of the Port 1 MII Basic
Control Register (P1_MII_BASIC_CONTROL) is set. Transmissions from the Switch Engine are not
sent to the external MAC. Instead, they are looped back internally onto the receive path. Transmissions
from the external MAC are ignored. An internal collision signal to the Switch Engine is available and
is asserted when the Switch Collision Test Port 1 bit is set. Switch Engine loopback occurs regardless
of the setting of the Isolate bit.
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Chapter 10 MII Management
10.1 Functional Overview
This chapter details the MII management functionality provided by the device, which includes the SMI
Slave Controller, PHY Management Interface (PMI), and the MII Mode Multiplexer. The SMI Slave
Controller is used for CPU management of the device via the MII pins, and allows CPU access to all
system CSRs. The PHY Management Interface (PMI) is used to access the internal PHYs and optional
external PHY, dependant on the management mode. The PMI implements the IEEE 802.3
management protocol. The MII Mode Multiplexer is used to direct the connections of the MII data path
and MII management path based on the selected mode of the device.
10.2 SMI Slave Controller
The SMI slave controller uses the same pins and protocol as the IEEE 802.3 MII management function,
and differs only in that SMI provides access to all internal registers by using a non-standard extended
addressing map. The SMI protocol co-exists with the MII management protocol by using the upper half
of the PHY address space (16 through 31). All direct and indirect registers can be accessed. The SMI
management mode is selected when the mngt_mode_strap[1:0] inputs are set to 01b. A list of
management modes and their configuration settings are discussed in Section 2.3, "Modes of
Operation," on page 19.
The MII management protocol is limited to 16-bit data accesses. The protocol is also limited to 5 PHY
address bits and 5 register address bits. The SMI frame format can be seen in Table 10.1. The device
uses the PHY Address field bits 3:0 as the system register address bits 9:6, and the Register Address
field as the system register address bits 5:1. Therefore, Register Address field bit 0 is used as the
upper/lower word select. The device requires two back-to-back accesses to each register (with
alternate settings of Register Address field bit 0) which are combined to form a 32-bit access. The
access may be performed in any order.
Note: When accessing the device, the pair of cycles must be atomic. In this case, the first host SMI
cycle is performed to the low/high word and the second host SMI cycle is performed to the
high/low word, forming a 32-bit transaction with no cycles to the device in between. With the
exception of Register Address field bit 0, all address and control bits must be the same for
both 16-bit cycles of a 32-bit transaction.
Input data on the MDIO pin is sampled on the rising edge of the MDC input clock. Output data is
sourced on the MDIO pin with the rising edge of the clock. The MDIO pin is three-stated unless actively
driving read data.
A read or a write is performed using the frame format shown in Table 10.1. All addresses and data are
transferred msb first. Data bytes are transferred little endian. When Register Address bit 0 is 1, bytes
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3 & 2 are selected with byte 3 occurring first. When Register Address bit 0 is 0, bytes 1 & 0 are
selected with byte 1 occurring first.
Note 10.1 PHY Address bit 4 is 1 for SMI commands. PHY Address 3:0 form system register address
bits 9:6. The Register Address field forms the system register address bits 5:1
Note 10.2 The turn-around time (TA) is used to avoid contention during a read cycle. For a read, the
device drives the second bit of the turn-around time to 0, and then drives the msb of the
read data in the following clock cycle. For a write, the external host drives the first bit of
the turn-around time to 1, the second bit of the turn-around time to 0, and then the msb
of the write data in the following clock cycle.
Note 10.3 In the IDLE condition, the MDIO output is three-stated and pulled high externally.
Note: The SMI interface supports up to a 2.5MHz input clock. The MII/SMI timing adheres to the
IEEE 802.3 specification. Refer to the IEEE 802.3 specification for detailed MII timing
information.
10.2.1 Read Sequence
In a read sequence, the host sends the 32-bit preamble, 2-bit start of frame, 2-bit op-code, 5-bit PHY
Address, and the 5-bit Register Address. The next clock is the first bit of the turnaround time in which
the device continues to three-state MDIO. On the next rising edge of MDC, the device drives MDIO
low. For the next 16 rising edges, the device drives the output data. On the final clock, the device once
again three-states MDIO.
The host processor is required to perform two consecutive 16-bit reads to complete a single DWORD
transfer. No ordering requirements exist. The processor can access either the low or high word first,
as long as the next read is performed from the other word. If a read to the same word is performed,
the combined data read pair is invalid and should be re-read. This is not a fatal error. The device will
simply reset the read counters, and restart a new cycle on the next read.
Note: Select registers are readable as 16-bit registers, as noted in their register descriptions. For
these registers, only one 16-bit read may be performed without the need to read the other
word.
Register values are latched (registered) at the beginning of each 16-bit read to prevent the host from
reading an intermediate value. In addition, any register that is affected by a read operation, such as a
clear on read bit, is not cleared until after the end of the second read. In the event that 32-bits are not
read, the read in considered invalid and the register is not affected.
Any register that may change between two consecutive host read cycles and spans across two
WORDs, such as a counter, is latched (registered) at the beginning of the first read and held until after
the second read has completed. This prevents the host from reading inconsistent data from the first
and second half of a register. For example, if a counters value is 01FFh, the first half will be read as
Table 10.1 SMI Frame Format
PREAMBLE START
OP
CODE
PHY
ADDRESS
Note 10.1
REGISTER
ADDRESS
Note 10.1
TURN-
AROUND
TIME
Note 10.2 DATA
IDLE
Note
10.3
READ 32 1’s 01 10 1AAAA
9876
AAAAA
54321
Z0 DDDDDDDDDDDDDDDD
1111110000000000
5432109876543210
Z
WRITE 32 1’s 01 01 1AAAA
9876
AAAAA
54321
10 DDDDDDDDDDDDDDDD
1111110000000000
5432109876543210
Z
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01h. If the counter then changes to 0200h, the host would read 00h, resulting an the incorrect value
of 0100h instead of either 01FFh or 0200h.
Note: SMI reads from unused register addresses return all zeros. This differs from unused PHY
registers which leave MDIO un-driven.
10.2.1.1 SMI Read Polling for Reset Complete
During reset, the SMI slave interface will not return valid data. To determine when the reset condition
is complete, the Byte Order Test Register (BYTE_TEST) should be polled. Once the correct pattern is
read, the interface can be considered functional. At this point, the Device Ready (READY) bit in the
Hardware Configuration Register (HW_CFG) can be polled to determine when the device initialization
is complete. Refer to Section 4.2, "Resets," on page 48 for additional information.
Note: In the event that a reset condition terminates between halves of 16-bit read pair, the device
will not expect another 16-bit read to complete the DWORD cycle. Only specific registers may
be read during a reset. Refer to Section 4.2, "Resets," on page 48 for additional information.
10.2.2 Write Sequence
In a write sequence, the host sends the 32-bit preamble, 2-bit start of frame, 2-bit op-code, 5-bit PHY
Address, 5-bit Register Address, 2-bit turn-around time, and finally the 16-bits of data. The MDIO pin
is three-stated throughout the write sequence.
The host processor is required to perform two contiguous 16-bit writes to complete a single DWORD
transfer. No ordering requirement exists. The host may access either the low or high word first, as long
as the next write is performed to the opposite word. If a write to the same word is performed, the device
disregards the transfer.
Note: SMI writes must not be performed to unused register addresses.
10.3 PHY Management Interface (PMI)
The PHY Management Interface (PMI) is used to access the internal PHYs as well as the external
PHY on the MII pins (in MAC modes only). The PMI operates at 2.5MHz, and implements the IEEE
802.3 management protocol, providing read/write commands for PHY configuration.
A read or write is performed using the frame format shown in Table 10.2. All addresses and data are
transferred msb first. Data bytes are transferred little endian.
Note 10.4 The turn-around time (TA) is used to avoid bus contention during a read cycle. For a read,
the external PHY drives the second bit of the turn-around time to 0, and then drives the
msb of the read data in the following cycle. For a write, the device drives the first bit of
the turnaround time to 1, the second bit of the turnaround time to 0, and then the msb of
the write data in the following clock cycle.
Note 10.5 In the IDLE condition, the MDIO output is three-stated and pulled high externally.
Table 10.2 MII Management Frame Format
PREAMBLE START
OP
CODE
PHY
ADDRESS
REGISTER
ADDRESS
TURN-
AROUND
TIME
Note 10.4 DATA
IDLE
Note
10.5
READ 32 1’s 01 10 AAAAA RRRRR Z0 DDDDDDDDDDDDDDDD Z
WRITE 32 1’s 01 01 AAAAA RRRRR 10 DDDDDDDDDDDDDDDD Z
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The internal PHYs and optional external PHY (in MAC modes) are accessed via the PHY Management
Interface Access Register (PMI_ACCESS) and PHY Management Interface Data Register
(PMI_DATA). These registers allow read and write operations to all PHY registers. Refer to Section
13.2.5, "PHY Management Interface (PMI)," on page 179 for detailed information on these registers.
10.3.1 EEPROM Loader PHY Register Access
The PMI is also used by the EEPROM Loader to load the PHY registers with various configuration
strap values. The PHY Management Interface Access Register (PMI_ACCESS) and PHY Management
Interface Data Register (PMI_DATA) are also accessible as part of the Register Data burst sequence
of the EEPROM Loader. Refer to Section 8.4, "EEPROM Loader," on page 121 for additional
information.
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10.4 MII Mode Multiplexer
The MII mode multiplexer is used to direct the MII data/management path connections. One master
(MAC via the MII pins, or PMI) is connected to the slaves (PHY via MII pins, Port 1/2 PHYs, Virtual
PHY, and SMI slave) dependant on the selected management mode of the device. The MII mode
multiplexer also performs the multiplexing of the read data signals from the slaves and controls the
output enable of the MII pins.
The following sections detail the operation of the MII mode multiplexer in each management mode. A
list of management modes and their configuration settings are discussed in Section 2.3, "Modes of
Operation," on page 19.
10.4.1 Port 0 MAC Mode SMI Managed
In Port 0 MAC mode SMI managed, the internal PHYs and SMI slave block are accessed via the MII
management pins. The Virtual PHY and PMI are not used in this mode.
The Virtual PHY interface is accessible via the SMI slave or the EEPROM Loader. Refer to Section
10.2, "SMI Slave Controller," on page 135 and Section 8.4, "EEPROM Loader," on page 121 for
additional information.
Figure 10.1 details the MII multiplexer management path connections for this mode.
Figure 10.1 MII Mux Management Path Connections - MAC Mode SMI Managed
SMI Slave
MDI
MDO
MDIO_ DIR
MDCLK Parallel
Master
Virtual PHY
MDI
MDO
MDIO_ DIR
MDCLK Parallel
Slave
PHY2
MDI
MDO
MDIO_ DIR
MDCLK
PHY1
MDI
MDO
MDIO_ DIR
MDCLK
Management
Mode Selection
MII Pins
MDI
MDO
MDIO_ DIR
MDC_IN
MDC_ OUT
MDC_ DIR
Management
Mode Selection
PMI
MDIMDO MDCLK
Parallel Slave
MDO_EnN
MDIO
MDC
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10.4.2 Port 0 MAC Mode I2C Managed
In MAC mode I2C managed, the internal PHYs and the external PHY are accessed via the PMI. The
SMI slave and the Virtual PHY are not used in this mode.
The Virtual PHY and PMI interfaces are accessible via the I2C slave interface or the EEPROM Loader.
Refer to Section 8.4, "EEPROM Loader," on page 121 for additional information.
Figure 10.2 details the MII multiplexer management path connections for this mode.
Figure 10.2 MII Mux Management Path Connections - MAC Mode I2C Managed
SMI Slave
MDI
MDO
MDIO_ DIR
MDCLK Parallel
Master
Virtual PHY
MDI
MDO
MDIO_ DIR
MDCLK Parallel
Slave
PHY2
MDI
MDO
MDIO_ DIR
MDCLK
PHY1
MDI
MDO
MDIO_ DIR
MDCLK
Management
Mode Selection
MII Pins
MDI
MDO
MDIO_ DIR
MDC_IN
MDC_ OUT
MDC_ DIR
Management
Mode Selection
PMI
MDIMDO MDCLK
Parallel Slave
MDO_EnN
MDIO
MDC
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10.4.3 Port 0 PHY Mode SMI Managed
In PHY mode SMI managed, the internal PHYs, Virtual PHY, and SMI slave block are accessed via
the MII management pins. The PMI is not used in this mode.
The Virtual PHY interface is accessible via the SMI slave or the EEPROM Loader. Refer to Section
10.2, "SMI Slave Controller," on page 135 and Section 8.4, "EEPROM Loader," on page 121 for
additional information.
Figure 10.1 details the MII multiplexer management path connections for this mode.
Figure 10.3 MII Mux Management Path Connections - PHY Mode SMI Managed
SMI Slave
MDI
MDO
MDIO_ DIR
MDCLK Parallel
Master
Virtual PHY
MDI
MDO
MDIO_ DIR
MDCLK Parallel
Slave
PHY2
MDI
MDO
MDIO_ DIR
MDCLK
PHY1
MDI
MDO
MDIO_ DIR
MDCLK
Management
Mode Selection
MII Pins
MDI
MDO
MDIO_ DIR
MDC_IN
MDC_ OUT
MDC_ DIR
Management
Mode Selection
PMI
MDIMDO MDCLK
Parallel Slave
MDO_EnN
MDIO
MDC
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10.4.4 Port 0 PHY Mode I2C Managed
In PHY mode I2C managed, the Port 1/2 PHYs are accessed via the PMI, and the Virtual PHY is
accessed via the external MII management pins. The SMI slave is not used in this mode.
The Virtual PHY and PMI parallel interfaces are accessible via the I2C slave interface or the EEPROM
Loader. Refer to Section 8.4, "EEPROM Loader," on page 121 for additional information.
Figure 10.2 details the MII multiplexer management path connections for this mode.
Figure 10.4 MII Mux Management Path Connections - PHY Mode I2C Managed
SMI Slave
MDI
MDO
MDIO_ DIR
MDCLK Parallel
Master
Virtual PHY
MDI
MDO
MDIO_ DIR
MDCLK Parallel
Slave
PHY2
MDI
MDO
MDIO_ DIR
MDCLK
PHY1
MDI
MDO
MDIO_ DIR
MDCLK
Management
Mode Selection
MII Pins
MDI
MDO
MDIO_ DIR
MDC_IN
MDC_ OUT
MDC_ DIR
Management
Mode Selection
PMI
MDIMDO MDCLK
Parallel Slave
MDO_EnN
MDIO
MDC
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Chapter 11 General Purpose Timer & Free-Running Clock
This chapter details the General Purpose Timer (GPT) and the Free-Running Clock.
11.1 General Purpose Timer
The device provides a 16-bit programmable General Purpose Timer that can be used to generate
periodic system interrupts. The resolution of this timer is 100uS.
The GPT loads the General Purpose Timer Count Register (GPT_CNT) with the value in the General
Purpose Timer Pre-Load (GPT_LOAD) field of the General Purpose Timer Configuration Register
(GPT_CFG) when the General Purpose Timer Enable (TIMER_EN) bit of the General Purpose Timer
Configuration Register (GPT_CFG) is asserted (1). On a chip-level reset, or when the General Purpose
Timer Enable (TIMER_EN) bit changes from asserted (1) to de-asserted (0), the General Purpose
Timer Pre-Load (GPT_LOAD) field is initialized to FFFFh. The General Purpose Timer Count Register
(GPT_CNT) is also initialized to FFFFh on reset. Software can write a pre-load value into the General
Purpose Timer Pre-Load (GPT_LOAD) field at any time (e.g. before or after the General Purpose Timer
Enable (TIMER_EN) bit is asserted).
Once enabled, the GPT counts down until it reaches 0000h, or until a new pre-load value is written to
the General Purpose Timer Pre-Load (GPT_LOAD) field. At 0000h, the counter wraps around to
FFFFh, asserts the GP Timer (GPT_INT) interrupt status bit in the Interrupt Status Register (INT_STS),
asserts the IRQ interrupt (if GP Timer Interrupt Enable (GPT_INT_EN) is set in the Interrupt Status
Register (INT_STS)), and continues counting. GP Timer (GPT_INT) is a sticky bit. Once this bit is
asserted, it can only be cleared by writing a 1 to the bit. Refer to Section 5.2.4, "General Purpose
Timer Interrupt," on page 65 for additional information on the GPT interrupt.
11.2 Free-Running Clock
The Free-Running Clock (FRC) is a simple 32-bit up-counter that operates from a fixed 25MHz clock.
The current FRC value can be read via the Free Running 25MHz Counter Register (FREE_RUN). On
assertion of a chip-level reset, this counter is cleared to zero. On de-assertion of a reset, the counter
is incremented once for every 25MHz clock cycle. When the maximum count has been reached, the
counter rolls over to zeros. The FRC does not generate interrupts.
Note: The free running counter can take up to 160nS to clear after a reset event.
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Chapter 12 GPIO/LED Controller
12.1 Functional Overview
The GPIO/LED Controller provides 6 configurable general purpose input/output pins, GPIO[5:0]. These
pins can be individually configured to function as inputs, push-pull outputs, or open drain outputs and
each is capable of interrupt generation with configurable polarity. Alternatively, all 6 GPIO pins can be
configured as LED outputs, enabling these pins to drive Ethernet status LEDs for external indication
of various attributes of the switch ports.
GPIO and LED functionality is configured via the GPIO/LED System Control and Status Registers
(CSRs). These registers are defined in Section 13.2.2, "GPIO/LED," on page 156.
12.2 GPIO Operation
The GPIO controller is comprised of 6 programmable input/output pins. These pins are individually
configurable via the GPIO CSRs. On application of a chip-level reset:
All GPIOs are set as inputs (GPIO Direction 5-0 (GPDIR[5:0]) cleared in General Purpose I/O Data
& Direction Register (GPIO_DATA_DIR))
All GPIO interrupts are disabled (GPIO Interrupt Enable[5:0] (GPIO[5:0]_INT_EN) cleared in
General Purpose I/O Interrupt Status and Enable Register (GPIO_INT_STS_EN)
All GPIO interrupts are configured to low logic level triggering (GPIO Interrupt Polarity 5-0
(GPIO_INT_POL[5:0]) cleared in General Purpose I/O Configuration Register (GPIO_CFG))
Note: GPIO[5:0] may be configured as LED outputs by default, dependant on the LED_en_strap[5:0]
configuration straps. Refer to Section 12.3, "LED Operation" for additional information.
The direction and buffer type of all 6 GPIOs are configured via the General Purpose I/O Configuration
Register (GPIO_CFG) and General Purpose I/O Data & Direction Register (GPIO_DATA_DIR). The
direction of each GPIO, input or output, should be configured first via its respective GPIO Direction 5-
0 (GPDIR[5:0]) bit in the General Purpose I/O Data & Direction Register (GPIO_DATA_DIR). When
configured as an output, the output buffer type for each GPIO is selected by the GPIO Buffer Type 5-
0 (GPIOBUF[5:0]) bits in the General Purpose I/O Configuration Register (GPIO_CFG). Push/pull and
open-drain output buffers are supported for each GPIO. When functioning as an open-drain driver, the
GPIO output pin is driven low when the corresponding GPIO Data 5-0 (GPIOD[5:0]) bit in the General
Purpose I/O Data & Direction Register (GPIO_DATA_DIR) is cleared to 0, and is not driven when set
to 1.
When a GPIO is enabled as a push/pull output, the value output to the GPIO pin is set via the
corresponding GPIO Data 5-0 (GPIOD[5:0]) bit in the General Purpose I/O Data & Direction Register
(GPIO_DATA_DIR). For GPIOs configured as inputs, the corresponding GPIO Data 5-0 (GPIOD[5:0])
bit reflects the current state of the GPIO input.
12.2.1 GPIO Interrupts
Each GPIO provides the ability to trigger a unique GPIO interrupt in the General Purpose I/O Interrupt
Status and Enable Register (GPIO_INT_STS_EN). Reading the GPIO Interrupt[5:0] (GPIO[5:0]_INT)
bits of this register provides the current status of the corresponding interrupt, and each interrupt is
enabled by setting the corresponding GPIO Interrupt Enable[5:0] (GPIO[5:0]_INT_EN) bit. The
GPIO/LED Controller aggregates the enabled interrupt values into an internal signal that is sent to the
System Interrupt Controller and is reflected via the Interrupt Status Register (INT_STS) GPIO Interrupt
Event (GPIO) bit. For more information on interrupts, refer to Chapter 5, "System Interrupts," on
page 62.
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12.2.1.1 GPIO Interrupt Polarity
The interrupt polarity can be set for each individual GPIO via the GPIO Interrupt Polarity 5-0
(GPIO_INT_POL[5:0]) bits in the General Purpose I/O Configuration Register (GPIO_CFG). When set,
a high logic level on the GPIO pin will set the corresponding interrupt bit in the General Purpose I/O
Interrupt Status and Enable Register (GPIO_INT_STS_EN). When cleared, a low logic level on the
GPIO pin will set the corresponding interrupt bit.
12.3 LED Operation
Each GPIO can be individually selected to function as a LED. These pins are configured as LED
outputs by setting the corresponding LED Enable 5-0 (LED_EN[5:0]) bit in the LED Configuration
Register (LED_CFG). When configured as a LED, the pin is either a push-pull or open-drain / open-
source output and the GPIO related input buffer and pull-up are disabled. The default configuration,
including polarity, is determined by input straps or EEPROM entries. Refer to Configuration Straps on
page 52 for additional information.
The functions associated with each LED pin are configurable via the LED Function 1-0 (LED_FUN[1:0])
bits of the LED Configuration Register (LED_CFG). These bits allow the configuration of each LED pin
to indicate various port related functions. These functions are described in Table 12.1, followed by a
detailed definition of each indication type.
The default values of the LED Function 1-0 (LED_FUN[1:0]) and LED Enable 5-0 (LED_EN[5:0]) bits
of the LED Configuration Register (LED_CFG) are determined by the LED_fun_strap[1:0] and
LED_en_strap[5:0] configuration straps. For more information on the LED Configuration Register
(LED_CFG) and its related straps, refer to Section 13.2.2.4, "LED Configuration Register (LED_CFG),"
on page 159.
Table 12.1 LED Operation as a Function of LED_FUN[1:0]
00b 01b 10b 11b
LED5
(GPIO5)
Link / Activity
Port 2
100Link / Activity
Port 2
TX
Port 0
TX_EN
Port 0
LED4
(GPIO4)
Full-duplex / Collision
Port 2
Full-duplex / Collision
Port 2
Link / Activity
Port 2
TX_EN
Port 2
LED3
(GPIO3)
Speed
Port 2
10Link / Activity
Port 2
Speed
Port 2
RX_DV
Port 2
LED2
(GPIO2)
Link / Activity
Port 1
(if Port 1 internal PHY
enabled)
Activity
Port 1
(if Port 1 internal PHY
disabled)
100Link / Activity
Port 1
(if Port 1 internal PHY
enabled)
Activity
Port 1
(if Port 1 internal PHY
disabled)
RX
Port 0
RX_DV
Port 0
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The various LED indication functions shown in Table 12.1 are described in the following sections.
12.3.1 LED Function Definitions when LED_FUN[1:0] = 00b, 01b, or 10b
When LED Function 1-0 (LED_FUN[1:0]) is 00b, 01b, or 10b, the following LED rules apply:
“Active” is defined as the pin being driven to the opposite value latched at reset on the
led_pol_strap[5:0] LED polarity hard-straps. LED polarity is determined by these hard-straps as
detailed in Section 4.2.4, "Configuration Straps," on page 52. The LED polarity cannot be modified
via soft-straps.
“Inactive” is defined as the pin not being driven.
The input buffers and pull-ups are disabled on the shared GPIO/LED pins.
When LED Function 1-0 (LED_FUN[1:0]) is 00b, 01b, or 10b, the following LED function definitions
apply:
TX Port 0/1 - The signal is pulsed active for 80mS to indicate activity from the Switch Fabric to the
external MII pins. This signal is then made inactive for a minimum of 80mS, after which the process
will repeat if TX activity is again detected.
Note: Link indication does not affect this function.
RX Port 0/1 - The signal is pulsed active for 80mS to indicate activity from the external MII pins
to the Switch Fabric. This signal is then made inactive for a minimum of 80mS, after which the
process will repeat if RX activity is again detected.
Note: Link indication does not affect this function.
Activity Port 0/1 - The signal is pulsed active for 80mS to indicate transmit or receive activity on
the port. The signal is then made inactive for a minimum of 80mS, after which the process will
repeat if RX or TX activity is again detected.
Note: The idle condition is inactive in contrast to that of the Link / Activity function.
Note: Link indication does not affect this function.
LED1
(GPIO1)
Full-duplex / Collision
Port 1
(if Port 1 internal PHY
enabled)
Inactive
(if Port 1 internal PHY
disabled)
Full-duplex / Collision
Port 1
(if Port 1 internal PHY
enabled)
Inactive
(if Port 1 internal PHY
disabled)
Link / Activity
Port 1
(if Port 1 internal PHY
enabled)
TX
Port 1
(if Port 1 internal PHY
disabled)
TX_EN
Port 1
LED0
(GPIO0)
Speed
Port 1
(if Port 1 internal PHY
enabled)
Activity
Port 0
(if Port 1 internal PHY
disabled)
10Link / Activity
Port 1
(if Port 1 internal PHY
enabled)
Activity
Port 0
(if Port 1 internal PHY
disabled)
Speed
Port 1
(if Port 1 internal PHY
enabled)
RX
Port 1
(if Port 1 internal PHY
disabled)
RX_DV
Port 1
Table 12.1 LED Operation as a Function of LED_FUN[1:0] (continued)
00b 01b 10b 11b
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Link / Activity Port 1/2 - A steady active output indicates that the port has a valid link, while a
steady inactive output indicates no link on the port. The signal is pulsed inactive for 80mS to
indicate transmit or receive activity on the port. The signal is then made active for a minimum of
80mS, after which the process will repeat if RX or TX activity is again detected.
Full-duplex / Collision Port 1/2 - A steady active output indicates the port is in full-duplex mode.
In half-duplex mode, the signal is pulsed active for 80mS to indicate a network collision. The signal
is then made inactive for a minimum of 80mS, after which the process will repeat if another collision
is detected. The signal will be held inactive if the port does not have a valid link.
Speed Port 1/2 - A steady active output indicates a valid link with a speed of 100Mbps. A steady
inactive output indicates a speed of 10Mbps. The signal will be held inactive if the port does not
have a valid link.
100Link / Activity Port 1/2 - A steady active output indicates the port has a valid link and the
speed is 100Mbps. The signal is pulsed inactive for 80mS to indicate TX or RX activity on the port.
The signal is then driven active for a minimum of 80mS, after which the process will repeat if RX
or TX activity is again detected. The signal will be held inactive if the port does not have a valid
link or the speed is not 100Mbps.
10Link / Activity Port 1/2 - A steady active output indicates the port has a valid link and the speed
is 10Mbps. The signal is pulsed inactive for 80mS to indicate transmit or receive activity on the
port. The signal is then driven active for a minimum of 80mS, after which the process will repeat if
RX or TX activity is again detected. This signal will be held inactive if the port does not have a
valid link or the speed is not 10Mbps.
12.3.2 LED Function Definitions when LED_FUN[1:0] = 11b
When LED Function 1-0 (LED_FUN[1:0]) is 11b, the following LED rules apply:
The LED pins are push-pull drivers.
The LED polarity does not depend upon the led_pol_strap[5:0] LED polarity hard-straps. The LED
pin is driven high when the function signal is high, and is driven low when the function signal is low.
The input buffers and pull-ups are disabled on the shared GPIO/LED pins.
When LED Function 1-0 (LED_FUN[1:0]) is 11b, the following LED function definitions apply:
TX_EN Port 0 - Non-stretched TX_EN signal from the Switch Fabric to the external MII pins.
Note: Link indication does not affect this function.
RX_DV Port 0 - Non-stretched RX_DV signal from the external MII pins to the Switch Fabric.
Note: Link indication does not affect this function.
TX_EN Port 1 - Non-stretched TX_EN signal from the Switch Fabric to the PHY or external MII
pins.
Note: Link indication does not affect this function.
RX_DV Port 1 - Non-stretched RX_DV signal from the PHY or external MII pins to the Switch
Fabric.
Note: Link indication does not affect this function.
TX_EN Port 2 - Non-stretched TX_EN signal from the Switch Fabric to the PHY.
Note: Link indication does not affect this function.
RX_DV Port 2 - Non-stretched RX_DV signal from the PHY to the Switch Fabric.
Note: Link indication does not affect this function.
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Chapter 13 Register Descriptions
This section describes the various control and status registers (CSR’s). These registers are broken
into 3 categories. The following sections detail the functionality and accessibility of all the registers
within each category:
Section 13.2, "System Control and Status Registers," on page 150
Section 13.3, "Ethernet PHY Control and Status Registers," on page 206
Section 13.4, "Switch Fabric Control and Status Registers," on page 228
Figure 13.1 contains an overall base register memory map of the device. This memory map is not
drawn to scale, and should be used for general reference only.
Note: Not all registers are memory mapped or directly addressable. For details on the accessibility
of the various registers, refer the register sub-sections listed above.
Figure 13.1 Base Register Memory Map
Base + 000h
04Ch
RESERVED
2E0h
...
2DCh
3FFh
Switch CSR Direct Data
Registers
200h
...
050h
Virtual PHY Registers
1C0h
1DCh
19Ch
Switch Interface Registers
1ACh
1B0h
PHY Management Interface
Registers
0A4h
0A8h
RESERVED
System CSRs
RESERVED
0ACh
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13.1 Register Nomenclature
Table 13.1 describes the register bit attribute notation used throughout this document.
Many of these register bit notations can be combined. Some examples of this are shown below:
R/W: Can be written. Will return current setting on a read.
R/WAC: Will return current setting on a read. Writing anything clears the bit.
Table 13.1 Register Bit Types
REGISTER BIT TYPE
NOTATION REGISTER BIT DESCRIPTION
RRead: A register or bit with this attribute can be read.
WRead: A register or bit with this attribute can be written.
RO Read only: Read only. Writes have no effect.
WO Write only: If a register or bit is write-only, reads will return unspecified data.
WC Write One to Clear: writing a one clears the value. Writing a zero has no effect
WAC Write Anything to Clear: writing anything clears the value.
RC Read to Clear: Contents is cleared after the read. Writes have no effect.
LL Latch Low: Clear on read of register.
LH Latch High: Clear on read of register.
SC Self-Clearing: Contents are self-cleared after the being set. Writes of zero have no
effect. Contents can be read.
SS Self-Setting: Contents are self-setting after being cleared. Writes of one have no
effect. Contents can be read.
RO/LH Read Only, Latch High: Bits with this attribute will stay high until the bit is read. After
it is read, the bit will either remain high if the high condition remains, or will go low if
the high condition has been removed. If the bit has not been read, the bit will remain
high regardless of a change to the high condition. This mode is used in some Ethernet
PHY registers.
NASR Not Affected by Software Reset. The state of NASR bits do not change on assertion
of a software reset.
RESERVED Reserved Field: Reserved fields must be written with zeros to ensure future
compatibility. The value of reserved bits is not guaranteed on a read.
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13.2 System Control and Status Registers
The System CSR’s are directly addressable memory mapped registers with a base address offset
range of 050h to 2DCh. These registers are accessed through the I2C serial interface or the MIIM/SMI
serial interface. For more information on the various modes and their corresponding address
configurations, see Section 2.3, "Modes of Operation," on page 19.
Table 13.2 lists the System CSR’s and their corresponding addresses in order. All system CSR’s are
reset to their default value on the assertion of a chip-level reset.
The System CSR’s can be divided into 7 sub-categories. Each of these sub-categories contains the
System CSR descriptions of the associated registers. The register descriptions are categorized as
follows:
Section 13.2.1, "Interrupts," on page 152
Section 13.2.2, "GPIO/LED," on page 156
Section 13.2.3, "EEPROM," on page 160
Section 13.2.4, "Switch Fabric," on page 164
Section 13.2.5, "PHY Management Interface (PMI)," on page 179
Section 13.2.6, "Virtual PHY," on page 181
Section 13.2.7, "Miscellaneous," on page 196
Table 13.2 System Control and Status Registers
ADDRESS
OFFSET SYMBOL REGISTER NAME
000h - 04Ch RESERVED Reserved for Future Use
050h ID_REV Chip ID and Revision Register, Section 13.2.7.1
054h IRQ_CFG Interrupt Configuration Register, Section 13.2.1.1
058h INT_STS Interrupt Status Register, Section 13.2.1.2
05Ch INT_EN Interrupt Enable Register, Section 13.2.1.3
060h RESERVED Reserved for Future Use
064h BYTE_TEST Byte Order Test Register, Section 13.2.7.2
068h - 070h RESERVED Reserved for Future Use
074h HW_CFG Hardware Configuration Register, Section 13.2.7.3
078h - 088h RESERVED Reserved for Future Use
08Ch GPT_CFG General Purpose Timer Configuration Register,
Section 13.2.7.4
090h GPT_CNT General Purpose Timer Count Register, Section 13.2.7.5
094h - 098h RESERVED Reserved for Future Use
09Ch FREE_RUN Free Running Counter Register, Section 13.2.7.6
0A0h RESERVED Reserved for Future Use
0A4h PMI_DATA PHY Management Interface Data Register,
Section 13.2.5.1
0A8h PMI_ACCESS PHY Management Interface Access Register,
Section 13.2.5.2
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0ACh - 19Ch RESERVED Reserved for Future Use
1A0h MANUAL_FC_1 Port 1 Manual Flow Control Register, Section 13.2.4.1
1A4h MANUAL_FC_2 Port 2 Manual Flow Control Register, Section 13.2.4.2
1A8h MANUAL_FC_0 Port 0 Manual Flow Control Register, Section 13.2.4.3
1ACh SWITCH_CSR_DATA Switch Fabric CSR Interface Data Register,
Section 13.2.4.4
1B0h SWITCH_CSR_CMD Switch Fabric CSR Interface Command Register,
Section 13.2.4.5
1B4h E2P_CMD EEPROM Command Register, Section 13.2.3.1
1B8h E2P_DATA EEPROM Data Register, Section 13.2.3.2
1BCh LED_CFG LED Configuration Register, Section 13.2.2.4
1C0h VPHY_BASIC_CTRL Virtual PHY Basic Control Register, Section 13.2.6.1
1C4h VPHY_BASIC_STATUS Virtual PHY Basic Status Register, Section 13.2.6.2
1C8h VPHY_ID_MSB Virtual PHY Identification MSB Register, Section 13.2.6.3
1CCh VPHY_ID_LSB Virtual PHY Identification LSB Register, Section 13.2.6.4
1D0h VPHY_AN_ADV Virtual PHY Auto-Negotiation Advertisement Register,
Section 13.2.6.5
1D4h VPHY_AN_LP_BASE_ABILITY Virtual PHY Auto-Negotiation Link Partner Base Page
Ability Register, Section 13.2.6.6
1D8h VPHY_AN_EXP Virtual PHY Auto-Negotiation Expansion Register,
Section 13.2.6.7
1DCh VPHY_SPECIAL_CONTROL_STATUS Virtual PHY Special Control/Status Register,
Section 13.2.6.8
1E0h GPIO_CFG General Purpose I/O Configuration Register,
Section 13.2.2.1
1E4h GPIO_DATA_DIR General Purpose I/O Data & Direction Register,
Section 13.2.2.2
1E8h GPIO_INT_STS_EN General Purpose I/O Interrupt Status and Enable Register,
Section 13.2.2.3
1ECh P1_MII_BASIC_CONTROL Port 1 MII Basic Control Register, Section 13.2.7.7
1F0h SWITCH_MAC_ADDRH Switch MAC Address High Register, Section 13.2.4.6
1F4h SWITCH_MAC_ADDRL Switch MAC Address Low Register, Section 13.2.4.7
1F8h RESET_CTL Reset Control Register, Section 13.2.7.8
1FCh RESERVED Reserved for Future Use
200h-2DCh SWITCH_CSR_DIRECT_DATA Switch Engine CSR Interface Direct Data Register,
Section 13.2.4.8
2E0h-3FFh RESERVED Reserved for Future Use
Table 13.2 System Control and Status Registers (continued)
ADDRESS
OFFSET SYMBOL REGISTER NAME
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13.2.1 Interrupts
This section details the interrupt related System CSR’s. These registers control, configure, and monitor
the IRQ interrupt output pin and the various interrupt sources. For more information on interrupts, refer
to Chapter 5, "System Interrupts," on page 62.
13.2.1.1 Interrupt Configuration Register (IRQ_CFG)
This read/write register configures and indicates the state of the IRQ signal.
Offset: 054h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:24 Interrupt De-assertion Interval (INT_DEAS)
This field determines the Interrupt Request De-assertion Interval in multiples
of 10 microseconds.
Setting this field to zero causes the device to disable the INT_DEAS Interval,
reset the interval counter and issue any pending interrupts. If a new, non-
zero value is written to this field, any subsequent interrupts will obey the new
setting.
R/W 00h
23:15 RESERVED RO -
14 Interrupt De-assertion Interval Clear (INT_DEAS_CLR)
Writing a 1 to this register clears the de-assertion counter in the Interrupt
Controller, thus causing a new de-assertion interval to begin (regardless of
whether or not the Interrupt Controller is currently in an active de-assertion
interval).
0: Normal operation
1: Clear de-assertion counter
R/W
SC
0h
13 Interrupt De-assertion Status (INT_DEAS_STS)
When set, this bit indicates that interrupts are currently in a de-assertion
interval, and will not be sent to the IRQ pin. When this bit is clear, interrupts
are not currently in a de-assertion interval, and will be sent to the IRQ pin.
0: No interrupts in de-assertion interval
1: Interrupts in de-assertion interval
RO
SC
0b
12 Master Interrupt (IRQ_INT)
This read-only bit indicates the state of the internal IRQ line, regardless of
the setting of the IRQ_EN bit, or the state of the interrupt de-assertion
function. When this bit is set, one of the enabled interrupts is currently
active.
0: No enabled interrupts active
1: One or more enabled interrupts active
RO 0b
11:9 RESERVED RO -
8IRQ Enable (IRQ_EN)
This bit controls the final interrupt output to the IRQ pin. When clear, the IRQ
output is disabled and permanently de-asserted. This bit has no effect on
any internal interrupt status bits.
0: Disable output on IRQ pin
1: Enable output on IRQ pin
R/W 0b
7:5 RESERVED RO -
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Note 13.1 Register bits designated as NASR are not reset when the Digital Reset (DIGITAL_RST) bit
in the Reset Control Register (RESET_CTL) is set.
4IRQ Polarity (IRQ_POL)
When cleared, this bit enables the IRQ line to function as an active low
output. When set, the IRQ output is active high. When the IRQ is configured
as an open-drain output (via the IRQ_TYPE bit), this bit is ignored, and the
interrupt is always active low.
0: IRQ active low output
1: IRQ active high output
R/W
NASR
Note 13.1
0b
3:1 RESERVED RO -
0IRQ Buffer Type (IRQ_TYPE)
When this bit is cleared, the IRQ pin functions as an open-drain output for
use in a wired-or interrupt configuration. When set, the IRQ is a push-pull
driver.
Note: When configured as an open-drain output, the IRQ_POL bit is
ignored and the interrupt output is always active low.
0: IRQ pin open-drain output
1: IRQ pin push-pull driver
R/W
NASR
Note 13.1
0b
BITS DESCRIPTION TYPE DEFAULT
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13.2.1.2 Interrupt Status Register (INT_STS)
This register contains the current status of the generated interrupts. A value of 1 indicates the
corresponding interrupt conditions have been met, while a value of 0 indicates the interrupt conditions
have not been met. The bits of this register reflect the status of the interrupt source regardless of
whether the source has been enabled as an interrupt in the Interrupt Enable Register (INT_EN). Where
indicated as R/WC, writing a 1 to the corresponding bits acknowledges and clears the interrupt.
Offset: 058h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31 Software Interrupt (SW_INT)
This interrupt is generated when the Software Interrupt Enable
(SW_INT_EN) bit of the Interrupt Enable Register (INT_EN) is set high.
Writing a one clears this interrupt.
R/WC 0b
30 Device Ready (READY)
This interrupt indicates that the device is ready to be accessed after a
power-up or reset condition.
R/WC 0b
29 RESERVED RO -
28 Switch Fabric Interrupt Event (SWITCH_INT)
This bit indicates an interrupt event from the Switch Fabric. This bit should
be used in conjunction with the Switch Global Interrupt Pending Register
(SW_IPR) to determine the source of the interrupt event within the Switch
Fabric.
RO 0b
27 Port 2 PHY Interrupt Event (PHY_INT2)
This bit indicates an interrupt event from the Port 2 PHY. The source of the
interrupt can be determined by polling the Port x PHY Interrupt Source
Flags Register (PHY_INTERRUPT_SOURCE_x).
RO 0b
26 Port 1 PHY Interrupt Event (PHY_INT1)
This bit indicates an interrupt event from the Port 1 PHY. The source of the
interrupt can be determined by polling the Port x PHY Interrupt Source
Flags Register (PHY_INTERRUPT_SOURCE_x).
RO 0b
25:20 RESERVED RO -
19 GP Timer (GPT_INT)
This interrupt is issued when the General Purpose Timer Count Register
(GPT_CNT) wraps past zero to FFFFh.
R/WC 0b
18:13 RESERVED RO -
12 GPIO Interrupt Event (GPIO)
This bit indicates an interrupt event from the General Purpose I/O. The
source of the interrupt can be determined by polling the General Purpose
I/O Interrupt Status and Enable Register (GPIO_INT_STS_EN)
RO 0b
11:0 RESERVED RO -
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13.2.1.3 Interrupt Enable Register (INT_EN)
This register contains the interrupt enables for the IRQ output pin. Writing 1 to any of the bits enables
the corresponding interrupt as a source for IRQ. Bits in the Interrupt Status Register (INT_STS) register
will still reflect the status of the interrupt source regardless of whether the source is enabled as an
interrupt in this register (with the exception of Software Interrupt Enable (SW_INT_EN)). For
descriptions of each interrupt, refer to the Interrupt Status Register (INT_STS) bits, which mimic the
layout of this register.
Offset: 05Ch Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31 Software Interrupt Enable (SW_INT_EN) R/W 0b
30 Device Ready Enable (READY_EN) R/W 0b
29 RESERVED RO -
28 Switch Fabric Interrupt Event Enable (SWITCH_INT_EN) R/W 0b
27 Port 2 PHY Interrupt Event Enable (PHY_INT2_EN) R/W 0b
26 Port 1 PHY Interrupt Event Enable (PHY_INT1_EN) R/W 0b
25:20 RESERVED RO -
19 GP Timer Interrupt Enable (GPT_INT_EN) R/W 0b
18:13 RESERVED RO -
12 GPIO Interrupt Event Enable (GPIO_EN) R/W 0b
11:0 RESERVED RO -
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13.2.2 GPIO/LED
This section details the General Purpose I/O (GPIO) and LED related System CSR’s.
13.2.2.1 General Purpose I/O Configuration Register (GPIO_CFG)
This read/write register configures the GPIO input and output pins. The polarity of the GPIO pins is
configured here.
Offset: 1E0h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:22 RESERVED RO -
21:16 GPIO Interrupt Polarity 5-0 (GPIO_INT_POL[5:0])
These bits set the interrupt polarity of the GPIO pins. The configured level
(high/low) will set the corresponding GPIO_INT bit in the General Purpose
I/O Interrupt Status and Enable Register (GPIO_INT_STS_EN).
0: Sets low logic level trigger on corresponding GPIO pin
1: Sets high logic level trigger on corresponding GPIO pin
R/W 0h
15:6 RESERVED RO -
5:0 GPIO Buffer Type 5-0 (GPIOBUF[5:0])
This field sets the buffer types of the GPIO pins.
0: Corresponding GPIO pin configured as an open-drain driver
1: Corresponding GPIO pin configured as a push/pull driver
As an open-drain driver, the output pin is driven low when the corresponding
data register is cleared, and is not driven when the corresponding data
register is set.
R/W 0h
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13.2.2.2 General Purpose I/O Data & Direction Register (GPIO_DATA_DIR)
This read/write register configures the direction of the GPIO pins and contains the GPIO input and
output data bits.
Offset: 1E4h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:22 RESERVED RO -
21:16 GPIO Direction 5-0 (GPDIR[5:0])
These bits set the input/output direction of the GPIO pins.
0: GPIO pin is configured as an input
1: GPIO pin is configured as an output
R/W 0h
15:6 RESERVED RO -
5:0 GPIO Data 5-0 (GPIOD[5:0])
When a GPIO pin is enabled as an output, the value written to this field is
output on the corresponding GPIO pin. Upon a read, the value returned
depends on the current direction of the pin. If the pin is an input, the data
reflects the current state of the corresponding GPIO pin. If the pin is an
output, the data is the value that was last written into this register. The pin
direction is determined by the GPDIR bits of this register.
R/W 0h
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13.2.2.3 General Purpose I/O Interrupt Status and Enable Register (GPIO_INT_STS_EN)
This read/write register contains the GPIO interrupt status bits.
Writing a 1 to any of the interrupt status bits acknowledges and clears the interrupt. If enabled, these
interrupt bits are cascaded into the GPIO Interrupt Event (GPIO) bit of the Interrupt Status Register
(INT_STS). Writing a 1 to any of the interrupt enable bits will enable the corresponding interrupt as a
source. Status bits will still reflect the status of the interrupt source regardless of whether the source
is enabled as an interrupt in this register. The GPIO Interrupt Event Enable (GPIO_EN) bit of the
Interrupt Enable Register (INT_EN) must also be set in order for an actual system level interrupt to
occur. Refer to Chapter 5, "System Interrupts," on page 62 for additional information.
Offset: 1E8h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:22 RESERVED RO -
21:16 GPIO Interrupt Enable[5:0] (GPIO[5:0]_INT_EN)
When set, these bits enable the corresponding GPIO interrupt.
Note: The GPIO interrupts must also be enabled via the GPIO Interrupt
Event Enable (GPIO_EN) bit of the Interrupt Enable Register
(INT_EN), in order to cause the interrupt pin (IRQ) to be asserted.
R/W 0h
15:6 RESERVED RO -
5:0 GPIO Interrupt[5:0] (GPIO[5:0]_INT)
These signals reflect the interrupt status as generated by the GPIOs. These
interrupts are configured through the General Purpose I/O Configuration
Register (GPIO_CFG).
Note: As GPIO interrupts, GPIO inputs are level sensitive and must be
active greater than 40 nS to be recognized as interrupt inputs.
R/WC 0h
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13.2.2.4 LED Configuration Register (LED_CFG)
This read/write register configures the GPIO[5:0] pins as LED[5:0] pins and sets their functionality.
Note 13.2 The default value of this field is determined by the configuration strap LED_fun_strap[1:0]].
Configuration strap values are latched on power-on reset or nRST de-assertion. Some
configuration straps can be overridden by values from the EEPROM Loader. Refer to
Section 4.2.4, "Configuration Straps," on page 52 for more information.
Note 13.3 The default value of this field is determined by the configuration strap LED_en_strap[5:0].
Configuration strap values are latched on power-on reset or nRST de-assertion. Some
configuration straps can be overridden by values from the EEPROM Loader. Refer to
Section 4.2.4, "Configuration Straps," on page 52 for more information.
Offset: 1BCh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:10 RESERVED RO -
9:8 LED Function 1-0 (LED_FUN[1:0])
These bits control the function associated with each LED pin as shown in
Table 12.1 of Section 12.3, "LED Operation," on page 145.
Note: In order for these assignments to be valid, the particular pin must
be enabled as an LED output pin via the LED_EN[5:0] bits of this
register.
R/W Note 13.2
7:6 RESERVED RO -
5:0 LED Enable 5-0 (LED_EN[5:0])
This field toggles the functionality of the GPIO[5:0] pins between GPIO and
LED.
0: Enables the associated pin as a GPIO signal
1: Enables the associated pin as a LED output
When configured as LED outputs, the pins are either push-pull or open-
drain/open-source outputs and the pull-ups and input buffers are disabled.
Push-pull is selected when LED_FUN[1:0] = 11b, otherwise, they are open-
drain/open-source. When open-drain/open-source, the polarity of the pins
depends upon the strap value sampled at reset. If a high is sampled at reset,
then this signal is active low.
Note: The polarity is determined by the strap value sampled on reset (a
hard-strap) and not the soft-strap value (of the shared strap) set via
EEPROM.
When configured as a GPIO output, the pins are configured per the General
Purpose I/O Configuration Register (GPIO_CFG) and the General Purpose
I/O Data & Direction Register (GPIO_DATA_DIR). The polarity of the pins
does not depend upon the strap value sampled at reset.
R/W Note 13.3
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13.2.3 EEPROM
This section details the EEPROM related System CSR’s. These registers should only be used if an
EEPROM has been connected to the device. Refer to chapter Section 8.3, "I2C Master EEPROM
Controller," on page 115 for additional information.
13.2.3.1 EEPROM Command Register (E2P_CMD)
This read/write register is used to control the read and write operations of the serial EEPROM.
Offset: 1B4h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31 EEPROM Controller Busy (EPC_BUSY)
When a 1 is written into this bit, the operation specified in the
EPC_COMMAND field of this register is performed at the specified
EEPROM address. This bit will remain set until the selected operation is
complete. In the case of a read, this indicates that the Host can read valid
data from the EEPROM Data Register (E2P_DATA). The E2P_CMD and
E2P_DATA registers should not be modified until this bit is cleared. In the
case where a write is attempted and an EEPROM is not present, the
EPC_BUSY bit remains set until the EEPROM Controller Timeout
(EPC_TIMEOUT) bit is set. At this time the EPC_BUSY bit is cleared.
Note: EPC_BUSY is set immediately following power-up, or pin reset, or
Digital Reset (DIGITAL_RST). After the EEPROM Loader has
finished loading, the EPC_BUSY bit is cleared. Refer to chapter
Section 8.4, "EEPROM Loader," on page 121 for more information.
R/W
SC
0b
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30:28 EEPROM Controller Command (EPC_COMMAND)
This field is used to issue commands to the EEPROM controller. The
EEPROM controller will execute a command when the EPC_BUSY bit is set.
A new command must not be issued until the previous command completes.
The field is encoded as follows:
Note: Only the READ, WRITE and RELOAD commands are valid for I2C
mode. If an unsupported command is attempted, the EPC_BUSY
bit will be cleared and EPC_TIMEOUT will be set.
The EEPROM operations are defined as follows:
READ (Read Location)
This command will cause a read of the EEPROM location pointed to by the
EPC_ADDRESS bit field. The result of the read is available in the EEPROM
Data Register (E2P_DATA).
WRITE (Write Location)
If erase/write operations are enabled in the EEPROM, this command will
cause the contents of the EEPROM Data Register (E2P_DATA) to be written
to the EEPROM location selected by the EPC_ADDRESS field.
RELOAD (EEPROM Loader Reload)
Instructs the EEPROM Loader to reload the device from the EEPROM. If a
value of A5h is not found in the first address of the EEPROM, the EEPROM
is assumed to be un-programmed and the RELOAD operation will fail. The
CFG_LOADED bit indicates a successful load. Following this command, the
device will enter the not ready state. The Device Ready (READY) bit in the
Hardware Configuration Register (HW_CFG) should be polled to determine
when the RELOAD is complete.
R/W 000b
27:19 RESERVED RO -
18 EEPROM Loader Address Overflow (LOADER_OVERFLOW)
This bit indicates that the EEPROM Loader tried to read past the end of the
EEPROM address space. This indicates misconfigured EEPROM data.
This bit is cleared when the EEPROM Loader is restarted with a RELOAD
command, or a Digital Reset (DIGITAL_RST).
RO 0b
17 EEPROM Controller Timeout (EPC_TIMEOUT)
This bit is set when a timeout occurs, indicating the last operation was
unsuccessful. If an EEPROM WRITE operation is performed, and no
response is received from the EEPROM within 30mS, the EEPROM
controller will timeout and return to its idle state.
The bit is also set if the EEPROM fails to respond with the appropriate
ACKs, if the EEPROM slave device holds the clock low for more than 30mS,
if the I2C bus is not acquired within 1.92 seconds, or if an unsupported
EPC_COMMAND is attempted.
This bit is cleared when written high.
R/WC 0b
BITS DESCRIPTION TYPE DEFAULT
[30] [29] [28] Operation
000 READ
0 0 1 RESERVED
0 1 0 RESERVED
011 WRITE
1 0 0 RESERVED
1 0 1 RESERVED
1 1 0 RESERVED
111 RELOAD
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16 Configuration Loaded (CFG_LOADED)
When set, this bit indicates that a valid EEPROM was found and the
EEPROM Loader completed normally. This bit is set upon a successful load.
It is cleared on power-up, pin and Digital Reset (DIGITAL_RST) resets, or
at the start of a RELOAD.
This bit is cleared when written high.
RO 0b
15:0 EEPROM Controller Address (EPC_ADDRESS)
This field is used by the EEPROM Controller to address a specific memory
location in the serial EEPROM. This address must be byte aligned.
R/W 0000h
BITS DESCRIPTION TYPE DEFAULT
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13.2.3.2 EEPROM Data Register (E2P_DATA)
This read/write register is used in conjunction with the EEPROM Command Register (E2P_CMD) to
perform read and write operations with the serial EEPROM.
Offset: 1B8h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:8 RESERVED RO -
7:0 EEPROM Data (EEPROM_DATA)
This field contains the data read from or written to the EEPROM.
R/W 00h
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13.2.4 Switch Fabric
This section details the memory mapped System CSR’s which are related to the Switch Fabric. The
flow control of all three ports of the Switch Fabric can be configured via the memory mapped System
CSR’s MANUAL_FC_1, MANUAL_FC_2 and MANUAL_FC_0. The MAC address used by the switch
for Pause frames is configured via the SWITCH_MAC_ADDRH and SWITCH_MAC_ADDRL registers.
In addition, the SWITCH_CSR_CMD, SWITCH_CSR_DATA and SWITCH_CSR_DIRECT_DATA
registers serve as a memory mapped accessible interface to the full range of otherwise inaccessible
switch control and status registers. A list of all the Switch Fabric CSRs can be seen in Table 13.14.
For additional information on the Switch Fabric, including a full explanation on how to use the Switch
Fabric CSR interface registers, refer to Chapter 6, "Switch Fabric," on page 67. For detailed
descriptions of the Switch Fabric CSR’s that are accessible via these interface registers, refer to
section Section 13.4, "Switch Fabric Control and Status Registers".
13.2.4.1 Port 1 Manual Flow Control Register (MANUAL_FC_1)
This read/write register allows for the manual configuration of the switch Port 1 flow control. This
register also provides read back of the currently enabled flow control settings, whether set manually
or Auto-Negotiated. Refer to Section 6.2.3, "Flow Control Enable Logic," on page 70 for additional
information.
Note: The flow control values in the PHY_AN_ADV_1 register (see Section 13.3.2.5, on page 214)
within the PHY are not affected by the values of this register.
Offset: 1A0h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:7 RESERVED RO -
6Port 1 Backpressure Enable (BP_EN_1)
This bit enables/disables the generation of half-duplex backpressure on
switch Port 1.
0: Disable backpressure
1: Enable backpressure
R/W Note 13.4
5Port 1 Current Duplex (CUR_DUP_1)
This bit indicates the actual duplex setting of switch Port 1.
0: Full-Duplex
1: Half-Duplex
RO Note 13.5
4Port 1 Current Receive Flow Control Enable (CUR_RX_FC_1)
This bit indicates the actual receive flow setting of switch Port 1.
0: Flow control receive is currently disabled
1: Flow control receive is currently enabled
RO Note 13.5
3Port 1 Current Transmit Flow Control Enable (CUR_TX_FC_1)
This bit indicates the actual transmit flow setting of switch Port 1.
0: Flow control transmit is currently disabled
1: Flow control transmit is currently enabled
RO Note 13.5
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Note 13.4 The default value of this field is determined by the BP_EN_strap_1 configuration strap. The
strap values are loaded during reset and can be re-written by the EEPROM Loader. Once
the EEPROM Loader re-writes the values, this register is updated with the new values.
See Section 4.2.4, "Configuration Straps," on page 52 for more information.
Note 13.5 The default value of this bit is determined by multiple strap settings. The strap values are
loaded during reset and can be re-written by the EEPROM Loader. Once the EEPROM
Loader re-writes the values, this register is updated with the new values. Refer to Section
6.2.3, "Flow Control Enable Logic," on page 70 for additional information.
Note 13.6 The default value of this field is determined by the FD_FC_strap_1 configuration strap. The
strap values are loaded during reset and can be re-written by the EEPROM Loader. Once
the EEPROM Loader re-writes the values, this register is updated with the new values.
See Section 4.2.4, "Configuration Straps," on page 52 for more information.
Note 13.7 The type is determined by the operating mode. In Port 1 MII PHY, RMII PHY, or MII MAC
mode, the type is RO. It is R/W for all other modes.
Note 13.8 The default value of this field is determined by the operating mode. In Port 1 MII PHY, RMII
PHY, or MII MAC mode, it is 1, and the bit is not re-written by the EEPROM Loader. For
all other operating modes, the default value is determined by the manual_FC_strap_1
configuration strap. The strap values are loaded during reset and can be re-written by the
EEPROM Loader. Once the EEPROM Loader re-writes the values, this register is updated
with the new values. See Section 4.2.4, "Configuration Straps," on page 52 for more
information.
2Port 1 Full-Duplex Receive Flow Control Enable (RX_FC_1)
When the MANUAL_FC_1 bit is set, or Auto-Negotiation is disabled, this bit
enables/disables the detection of full-duplex Pause packets on switch Port 1.
0: Disable flow control receive
1: Enable flow control receive
R/W Note 13.6
1Port 1 Full-Duplex Transmit Flow Control Enable (TX_FC_1)
When the MANUAL_FC_1 bit is set, or Auto-Negotiation is disabled, this bit
enables/disables full-duplex Pause packets to be generated on switch Port
1.
0: Disable flow control transmit
1: Enable flow control transmit
R/W Note 13.6
0Port 1 Full-Duplex Manual Flow Control Select (MANUAL_FC_1)
This bit toggles flow control selection between manual and auto-negotiation.
0: If auto-negotiation is enabled, the auto-negotiation function
determines the flow control of switch Port 1 (RX_FC_1 and TX_FC_1
values ignored). If auto-negotiation is disabled, the RX_FC_1 and
TX_FC_1 values are used.
1: TX_FC_1 and RX_FC_1 bits determine the flow control of switch Port
1 when in full-duplex mode.
Note: In Port 1 MII PHY, RMII PHY, or MII MAC mode, this bit is forced
high. There is no auto-negotiation capability. Full-duplex flow
control should be controlled manually by the host, if desired.
Note 13.7 Note 13.8
BITS DESCRIPTION TYPE DEFAULT
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13.2.4.2 Port 2 Manual Flow Control Register (MANUAL_FC_2)
This read/write register allows for the manual configuration of the switch Port 2 flow control. This
register also provides read back of the currently enabled flow control settings, whether set manually
or Auto-Negotiated. Refer to Section 6.2.3, "Flow Control Enable Logic," on page 70 for additional
information.
Note: The flow control values in the PHY_AN_ADV_2 register (see Section 13.3.2.5, on page 214)
within the PHY are not affected by the values of this register.
Offset: 1A4h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:7 RESERVED RO -
6Port 2 Backpressure Enable (BP_EN_2)
This bit enables/disables the generation of half-duplex backpressure on
switch Port 2.
0: Disable backpressure
1: Enable backpressure
R/W Note 13.9
5Port 2 Current Duplex (CUR_DUP_2)
This bit indicates the actual duplex setting of switch Port 2.
0: Full-Duplex
1: Half-Duplex
RO Note 13.10
4Port 2 Current Receive Flow Control Enable (CUR_RX_FC_2)
This bit indicates the actual receive flow setting of switch Port 2.
0: Flow control receive is currently disabled
1: Flow control receive is currently enabled
RO Note 13.10
3Port 2 Current Transmit Flow Control Enable (CUR_TX_FC_2)
This bit indicates the actual transmit flow setting of switch Port 2.
0: Flow control transmit is currently disabled
1: Flow control transmit is currently enabled
RO Note 13.10
2Port 2 Full-Duplex Receive Flow Control Enable (RX_FC_2)
When the MANUAL_FC_2 bit is set, or Auto-Negotiation is disabled, this bit
enables/disables the detection of full-duplex Pause packets on switch Port 2.
0: Disable flow control receive
1: Enable flow control receive
R/W Note 13.11
1Port 2 Full-Duplex Transmit Flow Control Enable (TX_FC_2)
When the MANUAL_FC_2 bit is set, or Auto-Negotiation is disabled, this bit
enables/disables full-duplex Pause packets to be generated on switch Port
2.
0: Disable flow control transmit
1: Enable flow control transmit
R/W Note 13.11
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Note 13.9 The default value of this field is determined by the BP_EN_strap_2 configuration strap. The
strap values are loaded during reset and can be re-written by the EEPROM Loader. Once
the EEPROM Loader re-writes the values, this register is updated with the new values.
See Section 4.2.4, "Configuration Straps," on page 52 for more information.
Note 13.10 The default value of this bit is determined by multiple strap settings. The strap values are
loaded during reset and can be re-written by the EEPROM Loader. Once the EEPROM
Loader re-writes the values, this register is updated with the new values. Refer to Section
6.2.3, "Flow Control Enable Logic," on page 70 for additional information.
Note 13.11 The default value of this field is determined by the FD_FC_strap_2 configuration strap. The
strap values are loaded during reset and can be re-written by the EEPROM Loader. Once
the EEPROM Loader re-writes the values, this register is updated with the new values.
See Section 4.2.4, "Configuration Straps," on page 52 for more information.
Note 13.12 The default value of this field is determined by the manual_FC_strap_2 configuration strap.
The strap values are loaded during reset and can be re-written by the EEPROM Loader.
Once the EEPROM Loader re-writes the values, this register is updated with the new
values. See Section 4.2.4, "Configuration Straps," on page 52 for more information.
0Port 2 Full-Duplex Manual Flow Control Select (MANUAL_FC_2)
This bit toggles flow control selection between manual and auto-negotiation.
0: If auto-negotiation is enabled, the auto-negotiation function
determines the flow control of switch Port 2 (RX_FC_2 and TX_FC_2
values ignored). If auto-negotiation is disabled, the RX_FC_2 and
TX_FC_2 values are used.
1: TX_FC_2 and RX_FC_2 bits determine the flow control of switch Port
2 when in full-duplex mode
R/W Note 13.12
BITS DESCRIPTION TYPE DEFAULT
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13.2.4.3 Port 0 Manual Flow Control Register (MANUAL_FC_0)
This read/write register allows for the manual configuration of the switch Port 0 flow control. This
register also provides read back of the currently enabled flow control settings, whether set manually
or Auto-Negotiated. Refer to Section 6.2.3, "Flow Control Enable Logic," on page 70 for additional
information.
Note: The flow control values in the Section 13.2.6.5, "Virtual PHY Auto-Negotiation Advertisement
Register (VPHY_AN_ADV)," on page 188 are not affected by the values of this register.
Offset: 1A8h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:7 RESERVED RO -
6Port 0 Backpressure Enable (BP_EN_0)
This bit enables/disables the generation of half-duplex backpressure on
switch Port 0.
0: Disable backpressure
1: Enable backpressure
R/W Note 13.13
5Port 0 Current Duplex (CUR_DUP_0)
This bit indicates the actual duplex setting of switch Port 0.
0: Full-Duplex
1: Half-Duplex
RO Note 13.14
4Port 0 Current Receive Flow Control Enable (CUR_RX_0)
This bit indicates the actual receive flow setting of switch Port 0
0: Flow control receive is currently disabled
1: Flow control receive is currently enabled
RO Note 13.14
3Port 0 Current Transmit Flow Control Enable (CUR_TX_FC_0)
This bit indicates the actual transmit flow setting of switch Port 0.
0: Flow control transmit is currently disabled
1: Flow control transmit is currently enabled
RO Note 13.14
2Port 0 Receive Flow Control Enable (RX_FC_0)
When the MANUAL_FC_0 bit is set, or Virtual Auto-Negotiation is disabled,
this bit enables/disables the detection of full-duplex Pause packets on switch
Port 0.
0: Disable flow control receive
1: Enable flow control receive
R/W Note 13.15
1Port 0 Transmit Flow Control Enable (TX_FC_0)
When the MANUAL_FC_0 bit is set, or Virtual Auto-Negotiation is disabled,
this bit enables/disables full-duplex Pause packets to be generated on
switch Port 0.
0: Disable flow control transmit
1: Enable flow control transmit
R/W Note 13.15
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Note 13.13 The default value of this field is determined by the BP_EN_strap_0 configuration strap. The
strap value is loaded during reset and can be re-written by the EEPROM Loader. Once
the EEPROM Loader re-writes the value, this register is updated with the new values. See
Section 4.2.4, "Configuration Straps," on page 52 for more information.
Note 13.14 The default value of this bit is determined by multiple strap settings. The strap values are
loaded during reset and can be re-written by the EEPROM Loader. Once the EEPROM
Loader re-writes the values, this register is updated with the new values. Refer to Section
6.2.3, "Flow Control Enable Logic," on page 70 for additional information.
Note 13.15 The default value of this field is determined by the FD_FC_strap_0 configuration strap. The
strap value is loaded during reset and can be re-written by the EEPROM Loader. Once
the EEPROM Loader re-writes the value, this register is updated with the new values. See
Section 4.2.4, "Configuration Straps," on page 52 for more information.
Note 13.16 This bit is RO when in MAC mode.
Note 13.17 The default value of this field is determined by the manual_FC_strap_0 configuration strap.
The strap value is loaded during reset and can be re-written by the EEPROM Loader. Once
the EEPROM Loader re-writes the value, this register is updated with the new values. In
MAC mode, this bit is not re-written by the EEPROM Loader and has a default value of
“1”. See Section 4.2.4, "Configuration Straps," on page 52 for more information.
0Port 0 Full-Duplex Manual Flow Control Select (MANUAL_FC_0)
This bit toggles flow control selection between manual and auto-negotiation.
0: If auto-negotiation is enabled, the auto-negotiation function
determines the flow control of switch Port 0 (RX_FC_0 and TX_FC_0
values ignored). If auto-negotiation is disabled, the RX_FC_0 and
TX_FC_0 values are used.
1: TX_FC_0 and RX_FC_0 bits determine the flow control of switch Port
0 when in full-duplex mode
Note: In MAC mode, this bit is forced high. The Virtual PHY is not
applicable in this mode and full-duplex flow control should be
controlled manually by the host based on the external PHYs Auto-
Negotiation results.
R/W
Note 13.16
Note 13.17
BITS DESCRIPTION TYPE DEFAULT
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13.2.4.4 Switch Fabric CSR Interface Data Register (SWITCH_CSR_DATA)
This read/write register is used in conjunction with the Switch Fabric CSR Interface Command Register
(SWITCH_CSR_CMD) to perform read and write operations with the Switch Fabric CSR’s. Refer to
Section 13.4, "Switch Fabric Control and Status Registers," on page 228 for details on the registers
indirectly accessible via this register.
Offset: 1ACh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Switch CSR Data (CSR_DATA)
This field contains the value read from or written to the Switch Fabric CSR.
The Switch Fabric CSR is selected via the CSR Address (CSR_ADDR[15:0])
bits of the Switch Fabric CSR Interface Command Register
(SWITCH_CSR_CMD).
Upon a read, the value returned depends on the Read/Write (R_nW) bit in
the Switch Fabric CSR Interface Command Register (SWITCH_CSR_CMD).
If Read/Write (R_nW) is set, the data is from the switch fabric. If Read/Write
(R_nW) is cleared, the data is the value that was last written into this
register.
R/W 00000000h
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13.2.4.5 Switch Fabric CSR Interface Command Register (SWITCH_CSR_CMD)
This read/write register is used in conjunction with the Switch Fabric CSR Interface Data Register
(SWITCH_CSR_DATA) to control the read and write operations to the various Switch Fabric CSR’s.
Refer to Section 13.4, "Switch Fabric Control and Status Registers," on page 228 for details on the
registers indirectly accessible via this register.
Offset: 1B0h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31 CSR Busy (CSR_BUSY)
When a 1 is written to this bit, the read or write operation (as determined by
the R_nW bit) is performed to the specified Switch Fabric CSR in CSR
Address (CSR_ADDR[15:0]). This bit will remain set until the operation is
complete, at which time the bit will clear. In the case of a read, the clearing
of this bit indicates to the Host that valid data can be read from the Switch
Fabric CSR Interface Data Register (SWITCH_CSR_DATA). The
SWITCH_CSR_CMD and SWITCH_CSR_DATA registers should not be
modified until this bit is cleared.
R/W
SC
0b
30 Read/Write (R_nW)
This bit determines whether a read or write operation is performed by the
Host to the specified Switch Engine CSR.
0: Write
1: Read
R/W 0b
29 Auto Increment (AUTO_INC)
This bit enables/disables the auto increment feature.
When this bit is set, a write to the Switch Fabric CSR Interface Data Register
(SWITCH_CSR_DATA) register will automatically set the CSR Busy
(CSR_BUSY) bit. Once the write command is finished, the CSR Address
(CSR_ADDR[15:0]) will automatically increment.
When this bit is set, a read from the Switch Fabric CSR Interface Data
Register (SWITCH_CSR_DATA) will automatically increment the CSR
Address (CSR_ADDR[15:0]) and set the CSR Busy (CSR_BUSY) bit. This
bit should be cleared by software before the last read from the
SWITCH_CSR_DATA register.
0: Disable Auto Increment
1: Enable Auto Increment
Note: This bit has precedence over the Auto Decrement (AUTO_DEC) bit
R/W 0b
28 Auto Decrement (AUTO_DEC)
This bit enables/disables the auto decrement feature.
When this bit is set, a write to the Switch Fabric CSR Interface Data Register
(SWITCH_CSR_DATA) will automatically set the CSR Busy (CSR_BUSY)
bit. Once the write command is finished, the CSR Address
(CSR_ADDR[15:0]) will automatically decrement.
When this bit is set, a read from the Switch Fabric CSR Interface Data
Register (SWITCH_CSR_DATA) will automatically decrement the CSR
Address (CSR_ADDR[15:0]) and set the CSR Busy (CSR_BUSY) bit. This
bit should be cleared by software before the last read from the
SWITCH_CSR_DATA register.
0: Disable Auto Decrement
1: Enable Auto Decrement
R/W 0b
27:20 RESERVED RO -
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19:16 CSR Byte Enable (CSR_BE[3:0])
This field is a 4-bit byte enable used for selection of valid bytes during write
operations. Bytes which are not selected will not be written to the
corresponding Switch Engine CSR.
CSR_BE[3] corresponds to register data bits [31:24]
CSR_BE[2] corresponds to register data bits [23:16]
CSR_BE[1] corresponds to register data bits [15:8]
CSR_BE[0] corresponds to register data bits [7:0]
Typically all four byte enables should be set for auto increment and auto
decrement operations.
R/W 0h
15:0 CSR Address (CSR_ADDR[15:0])
This field selects the 16-bit address of the Switch Fabric CSR that will be
accessed with a read or write operation. Refer to Table 13.14, “Indirectly
Accessible Switch Control and Status Registers,” on page 228 for a list of
Switch Fabric CSR addresses.
R/W 00h
BITS DESCRIPTION TYPE DEFAULT
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13.2.4.6 Switch Fabric MAC Address High Register (SWITCH_MAC_ADDRH)
This register contains the upper 16-bits of the MAC address used by the switch for Pause frames. This
register is used in conjunction with Switch Fabric MAC Address Low Register
(SWITCH_MAC_ADDRL). The contents of this register are optionally loaded from the EEPROM at
power-on through the EEPROM Loader if a programmed EEPROM is detected. The least significant
byte of this register (bits [7:0]) is loaded from address 05h of the EEPROM. The second byte (bits
[15:8]) is loaded from address 06h of the EEPROM. The Host can update the contents of this field
after the initialization process has completed.
Refer to Section 13.2.4.7, "Switch Fabric MAC Address Low Register (SWITCH_MAC_ADDRL)" for
information on how this address is loaded by the EEPROM Loader. Section 8.4, "EEPROM Loader,"
on page 121 contains additional details on using the EEPROM Loader.
Offset: 1F0h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:23 RESERVED RO -
22 DiffPauseAddr
When set, each port may have a unique MAC address.
R/W 0b
21:20 Port 2 Physical Address [41:40]
When DiffPauseAddr is set, these bits are used as bits 41 and 40 of the
MAC Address for Port 2.
R/W 10b
19:18 Port 1 Physical Address [41:40]
When DiffPauseAddr is set, these bits are used as bits 41 and 40 of the
MAC Address for Port 1.
R/W 01b
17:16 Port 0 Physical Address [41:40]
When DiffPauseAddr is set, these bits are used as bits 41 and 40 of the
MAC Address for Port 0.
R/W 00b
15:0 Physical Address[47:32]
This field contains the upper 16-bits (47:32) of the physical address of the
Switch Fabric MACs. Bits 41 and 10 are ignored if DiffPauseAddr is set.
R/W FFFFh
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13.2.4.7 Switch Fabric MAC Address Low Register (SWITCH_MAC_ADDRL)
This register contains the lower 32-bits of the MAC address used by the switch for Pause frames. This
register is used in conjunction with Switch Fabric MAC Address High Register
(SWITCH_MAC_ADDRH). The contents of this register are optionally loaded from the EEPROM at
power-on through the EEPROM Loader if a programmed EEPROM is detected. The least significant
byte of this register (bits [7:0]) is loaded from address 01h of the EEPROM. The most significant byte
(bits [31:24]) is loaded from address 04h of the EEPROM. The Host can update the contents of this
field after the initialization process has completed.
Refer to Section 8.4, "EEPROM Loader," on page 121 for information on using the EEPROM Loader.
Table 13.3 illustrates the byte ordering of the SWITCH_MAC_ADDRL and SWITCH_MAC_ADDRH
registers with respect to the reception of the Ethernet physical address. Also shown is the correlation
between the EEPROM addresses and the SWITCH_MAC_ADDRL and SWITCH_MAC_ADDRH
registers.
For example, if the desired Ethernet physical address is 12-34-56-78-9A-BC, the
SWITCH_MAC_ADDRL and SWITCH_MAC_ADDRH registers would be programmed as shown in
Figure 13.2. The values required to automatically load this configuration from the EEPROM are also
shown.
Offset: 1F4h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Physical Address[31:0]
This field contains the lower 32-bits (31:0) of the physical address of the
Switch Fabric MACs.
R/W FF0F8000h
Table 13.3 SWITCH_MAC_ADDRL, SWITCH_MAC_ADDRH, and EEPROM Byte Ordering
EEPROM Address Register Location Written Order of Reception on Ethernet
01h SWITCH_MAC_ADDRL[7:0] 1st
02h SWITCH_MAC_ADDRL[15:8] 2nd
03h SWITCH_MAC_ADDRL[23:16] 3rd
04h SWITCH_MAC_ADDRL[31:24] 4th
05h SWITCH_MAC_ADDRH[7:0] 5th
06h SWITCH_MAC_ADDRH[15:8] 6th
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Note: By convention, the right nibble of the left most byte of the Ethernet address (in this example,
the 2 of the 12h) is the most significant nibble and is transmitted/received first.
Figure 13.2 Example SWITCH_MAC_ADDRL, SWITCH_MAC_ADDRH, and EEPROM Setup
12h
07
34h
815
56h
1623
78h
2431
9AhBChxxxx
A5h
12h
34h
56h
78h
9Ah
BCh
00h
01h
02h
03h
04h
05h
06h
EEPROM
SWITCH_MAC_ADDRL
SWITCH_MAC_ADDRH
0781516232431
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13.2.4.8 Switch Fabric CSR Interface Direct Data Registers (SWITCH_CSR_DIRECT_DATA)
This write-only register set is used to perform directly addressed write operations to the Switch Fabric
CSR’s. Using this set of registers, writes can be directly addressed to select Switch Fabric registers,
as specified in Table 13.4.
Writes within the Switch Fabric CSR Interface Direct Data Registers (SWITCH_CSR_DIRECT_DATA)
address range automatically set the appropriate CSR Address (CSR_ADDR[15:0]), set the four CSR
Byte Enable (CSR_BE[3:0]) bits, clear the Read/Write (R_nW) bit and set the CSR Busy (CSR_BUSY)
bit in the Switch Fabric CSR Interface Command Register (SWITCH_CSR_CMD). The completion of
the write cycle is indicated when the CSR Busy (CSR_BUSY) bit is cleared. The address that is set
in the Switch Fabric CSR Interface Command Register (SWITCH_CSR_CMD) is mapped via
Table 13.4. For more information on this method of writing to the Switch Fabric CSR’s, refer to Section
6.2.3, "Flow Control Enable Logic," on page 70.
Note: This set of registers is for write operations only. Reads can be performed via the Switch Fabric
CSR Interface Command Register (SWITCH_CSR_CMD) and Switch Fabric CSR Interface
Data Register (SWITCH_CSR_DATA) registers only.
Offset: 200h - 2DCh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Switch CSR Data (CSR_DATA)
This field contains the value to be written to the corresponding Switch Fabric
register.
WO 00000000h
Table 13.4 Switch Fabric CSR to SWITCH_CSR_DIRECT_DATA Address Range Map
REGISTER NAME
SWITCH FABRIC CSR
REGISTER #
SWITCH_CSR_DIRECT_DATA
ADDRESS
General Switch CSRs
SW_RESET 0001h 200h
SW_IMR 0004h 204h
Switch Port 0 CSRs
MAC_RX_CFG_0 0401h 208h
MAC_TX_CFG_0 0440h 20Ch
MAC_TX_FC_SETTINGS_0 0441h 210h
MAC_IMR_0 0480h 214h
Switch Port 1 CSRs
MAC_RX_CFG_1 0801h 218h
MAC_TX_CFG_1 0840h 21Ch
MAC_TX_FC_SETTINGS_1 0841h 220h
MAC_IMR_1 0880h 224h
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Switch Port 2 CSRs
MAC_RX_CFG_2 0C01h 228h
MAC_TX_CFG_2 0C40h 22Ch
MAC_TX_FC_SETTINGS_2 0C41h 230h
MAC_IMR_2 0C80h 234h
Switch Engine CSRs
SWE_ALR_CMD 1800h 238h
SWE_ALR_WR_DAT_0 1801h 23Ch
SWE_ALR_WR_DAT_1 1802h 240h
SWE_ALR_CFG 1809h 244h
SWE_VLAN_CMD 180Bh 248h
SWE_VLAN_WR_DATA 180Ch 24Ch
SWE_DIFFSERV_TBL_CMD 1811h 250h
SWE_DIFFSERV_TBL_WR_DATA 1812h 254h
SWE_GLB_INGRESS_CFG 1840h 258h
SWE_PORT_INGRESS_CFG 1841h 25Ch
SWE_ADMT_ONLY_VLAN 1842h 260h
SWE_PORT_STATE 1843h 264h
SWE_PRI_TO_QUE 1845h 268h
SWE_PORT_MIRROR 1846h 26Ch
SWE_INGRESS_PORT_TYP 1847h 270h
SWE_BCST_THROT 1848h 274h
SWE_ADMT_N_MEMBER 1849h 278h
SWE_INGRESS_RATE_CFG 184Ah 27Ch
SWE_INGRESS_RATE_CMD 184Bh 280h
SWE_INGRESS_RATE_WR_DATA 184Dh 284h
SWE_INGRESS_REGEN_TBL_0 1855h 288h
SWE_INGRESS_REGEN_TBL_1 1856h 28Ch
SWE_INGRESS_REGEN_TBL_2 1857h 290h
SWE_IMR 1880h 294h
Buffer Manager (BM) CSRs
Table 13.4 Switch Fabric CSR to SWITCH_CSR_DIRECT_DATA Address Range Map (continued)
REGISTER NAME
SWITCH FABRIC CSR
REGISTER #
SWITCH_CSR_DIRECT_DATA
ADDRESS
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BM_CFG 1C00h 298h
BM_DROP_LVL 1C01h 29Ch
BM_FC_PAUSE_LVL 1C02h 2A0h
BM_FC_RESUME_LVL 1C03h 2A4h
BM_BCST_LVL 1C04h 2A8h
BM_RNDM_DSCRD_TBL_CMD 1C09h 2ACh
BM_RNDM_DSCRD_TBL_WDATA 1C0Ah 2B0h
BM_EGRSS_PORT_TYPE 1C0Ch 2B4h
BM_EGRSS_RATE_00_01 1C0Dh 2B8h
BM_EGRSS_RATE_02_03 1C0Eh 2BCh
BM_EGRSS_RATE_10_11 1C0Fh 2C0h
BM_EGRSS_RATE_12_13 1C10h 2C4h
BM_EGRSS_RATE_20_21 1C11h 2C8h
BM_EGRSS_RATE_22_23 1C12h 2CCh
BM_VLAN_0 1C13h 2D0h
BM_VLAN_1 1C14h 2D4h
BM_VLAN_2 1C15h 2D8h
BM_IMR 1C20h 2DCh
Table 13.4 Switch Fabric CSR to SWITCH_CSR_DIRECT_DATA Address Range Map (continued)
REGISTER NAME
SWITCH FABRIC CSR
REGISTER #
SWITCH_CSR_DIRECT_DATA
ADDRESS
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13.2.5 PHY Management Interface (PMI)
The PMI registers are used to indirectly access the PHY registers. Refer to Section 13.3, "Ethernet
PHY Control and Status Registers," on page 206 for additional information on the PHY registers. Refer
to Section 10.3, "PHY Management Interface (PMI)," on page 137 for information on the PMI.
Note: The Virtual PHY registers are NOT accessible via these registers.
13.2.5.1 PHY Management Interface Data Register (PMI_DATA)
This register is used in conjunction with the PHY Management Interface Access Register
(PMI_ACCESS) to perform read and write operations to the PHYs.
Note: The Virtual PHY registers are NOT accessible via these registers.
Offset: 0A4h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED RO -
15:0 MII Data
This field contains the value read from or written to the PHYs. For a write
operation, this register should be first written with the desired data. For a
read operation, the PMI_ACCESS register is first written and once the
command is finished, this register will contain the return data.
Note: Upon a read, the value returned depends on the MII Write
(MIIWnR) bit in the PHY Management Interface Access Register
(PMI_ACCESS). If MII Write (MIIWnR) is 0, the data is from the
PHY. If MII Write (MIIWnR) is 1, the data is the value that was last
written into this register.
R/W 0000h
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13.2.5.2 PHY Management Interface Access Register (PMI_ACCESS)
This register is used to control the management cycles to the PHYs. A PHY access is initiated when
this register is written. This register is used in conjunction with the PHY Management Interface Data
Register (PMI_DATA) to perform read and write operations to the PHYs.
Note: The Virtual PHY registers are NOT accessible via these registers.
Offset: 0A8h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED RO -
15:11 PHY Address (PHY_ADDR)
These bits select the PHY device being accessed. Refer to Section 7.1.1,
"PHY Addressing," on page 96 for information on PHY address
assignments.
R/W 00000b
10:6 MII Register Index (MIIRINDA)
These bits select the desired MII register in the PHY. Refer to Section 13.3,
"Ethernet PHY Control and Status Registers," on page 206 for detailed
descriptions on all PHY registers.
R/W 00000b
5:2 RESERVED RO -
1MII Write (MIIWnR)
Setting this bit informs the PHY that the access will be a write operation
using the PHY Management Interface Data Register (PMI_DATA). If this bit
is cleared, the access will be a read operation, returning data into the PHY
Management Interface Data Register (PMI_DATA).
R/W 0b
0MII Busy (MIIBZY)
This bit must be read as 0 before writing to the PHY Management Interface
Data Register (PMI_DATA) or PHY Management Interface Access Register
(PMI_ACCESS) registers. This bit is automatically set when this register is
written. During a PHY register access, this bit will be set, signifying a read
or write access is in progress. This is a self-clearing (SC) bit that will return
to 0 when the PHY register access has completed.
During a PHY register write, the PHY Management Interface Data Register
(PMI_DATA) must be kept valid until this bit is cleared.
During a PHY register read, the PHY Management Interface Data Register
(PMI_DATA) register is invalid until the MAC has cleared this bit.
RO
SC
0b
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13.2.6 Virtual PHY
This section details the Virtual PHY System CSR’s. These registers provide status and control
information similar to that of a real PHY while maintaining IEEE 802.3 compatibility. The Virtual PHY
registers are addressable via the memory map, as described in Table 13.2, as well as serially via the
MII management protocol (IEEE 802.3 clause 22). When accessed serially, these registers are
accessed through the MII management pins (in PHY modes only) via the MII serial management
protocol specified in IEEE 802.3 clause 22. See Section 2.3, "Modes of Operation," on page 19 for a
detailed description of the various device modes. When being accessed serially, the Virtual PHY will
respond when the PHY address equals the address assigned by the phy_addr_sel_strap configuration
strap, as defined in Section 7.1.1, "PHY Addressing," on page 96. A list of all Virtual PHY register
indexes for serial access can be seen in Table 13.5. For more information on the Virtual PHY access
modes, refer to section Section 13.3. For Virtual PHY functionality and operation information, see
Section 7.3, "Virtual PHY," on page 110.
Note: All Virtual PHY registers follow the IEEE 802.3 (clause 22.2.4) specified MII management
register set. All functionality and bit definitions comply with these standards. The IEEE 802.3
specified register index (in decimal) is included under the memory mapped offset of each
Virtual PHY register as a reference. For additional information, refer to the IEEE 802.3
Specification.
Note: When serially accessed, the Virtual PHY registers are only 16-bits wide, as is standard for MII
management of PHY’s.
Table 13.5 Virtual PHY MII Serially Adressable Register Index
INDEX # SYMBOL REGISTER NAME
0 VPHY_BASIC_CTRL Virtual PHY Basic Control Register, Section 13.2.6.1
1 VPHY_BASIC_STATUS Virtual PHY Basic Status Register, Section 13.2.6.2
2 VPHY_ID_MSB Virtual PHY Identification MSB Register, Section 13.2.6.3
3 VPHY_ID_LSB Virtual PHY Identification LSB Register, Section 13.2.6.4
4 VPHY_AN_ADV Virtual PHY Auto-Negotiation Advertisement Register,
Section 13.2.6.5
5VPHY_AN_LP_BASE_ABILITY Virtual PHY Auto-Negotiation Link Partner Base Page Ability
Register, Section 13.2.6.6
6 VPHY_AN_EXP Virtual PHY Auto-Negotiation Expansion Register,
Section 13.2.6.7
31 VPHY_SPEC_CTRL_STATUS Virtual PHY Special Control/Status Register, Section 13.2.6.8
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13.2.6.1 Virtual PHY Basic Control Register (VPHY_BASIC_CTRL)
This read/write register is used to configure the Virtual PHY.
Note: This register is re-written in its entirety by the EEPROM Loader following the release or reset
or a RELOAD command. Refer to Section 8.4, "EEPROM Loader," on page 121 for more
information.
Offset:
Index (decimal):
1C0h
0
Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED
(See Note 13.18)
RO -
15 Reset (VPHY_RST)
When set, this bit resets all the Virtual PHY registers to their default state.
This bit is self clearing.
0: Normal Operation
1: Reset
R/W
SC
0b
14 Loopback (VPHY_LOOPBACK)
This bit enables/disables the loopback mode. When enabled, transmissions
from the external MAC are not sent to the Switch Fabric. Instead, they are
looped back onto the receive path.
0: Loopback mode disabled (normal operation)
1: Loopback mode enabled
R/W 0b
13 Speed Select LSB (VPHY_SPEED_SEL_LSB)
This bit is used to set the speed of the Virtual PHY when the Auto-
Negotiation (VPHY_AN) bit is disabled.
0: 10 Mbps
1: 100/200 Mbps
R/W 0b
12 Auto-Negotiation (VPHY_AN)
This bit enables/disables Auto-Negotiation. When enabled, the Speed Select
LSB (VPHY_SPEED_SEL_LSB) and Duplex Mode (VPHY_DUPLEX) bits
are overridden.
0: Auto-Negotiation disabled
1: Auto-Negotiation enabled
R/W 1b
11 Power Down (VPHY_PWR_DWN)
This bit is not used by the Virtual PHY and has no effect.
R/W 0b
10 Isolate (VPHY_ISO)
This bit controls the MII input/output pins. When set and in MII/RMII PHY
mode, the MII output pins are not driven, MII pull-ups and pull-downs are
disabled and the input pins are ignored. When in MAC mode, this bit is
ignored and has no effect. (Note 13.19)
0: Non-Isolated (Normal operation)
1: Isolated
R/W 0b
9Restart Auto-Negotiation (VPHY_RST_AN)
When set, this bit updates the emulated Auto-Negotiation results.
0: Normal operation
1: Auto-Negotiation restarted
R/W
SC
0b
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Note 13.18 The reserved bits 31-16 are used to pad the register to 32-bits so that each register is on
a DWORD boundary. When accessed serially (through the MII management protocol), the
register is 16-bits wide.
Note 13.19 The isolation does not apply to the MII management pins (MDIO).
8Duplex Mode (VPHY_DUPLEX)
This bit is used to set the duplex when the Auto-Negotiation (VPHY_AN) bit
is disabled.
0: Half Duplex
1: Full Duplex
R/W 0b
7Collision Test (VPHY_COL_TEST)
This bit enables/disables the collision test mode. When set, the collision
signal to the external MAC is active during transmission from the external
MAC.
Note: It is recommended that this bit be used only when in loopback
mode.
0: Collision test mode disabled
1: Collision test mode enabled
R/W 0b
6Speed Select MSB (VPHY_SPEED_SEL_MSB)
This bit is not used by the Virtual PHY and has no effect. The value returned
is always 0.
RO 0b
5:0 RESERVED RO -
BITS DESCRIPTION TYPE DEFAULT
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13.2.6.2 Virtual PHY Basic Status Register (VPHY_BASIC_STATUS)
This register is used to monitor the status of the Virtual PHY.
Offset:
Index (decimal):
1C4h
1
Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED
(See Note 13.20)
RO -
15 100BASE-T4
This bit displays the status of 100BASE-T4 compatibility.
0: PHY not able to perform 100BASE-T4
1: PHY able to perform 100BASE-T4
RO 0b
Note 13.21
14 100BASE-X Full Duplex
This bit displays the status of 100BASE-X full duplex compatibility.
0: PHY not able to perform 100BASE-X full duplex
1: PHY able to perform 100BASE-X full duplex
RO 1b
13 100BASE-X Half Duplex
This bit displays the status of 100BASE-X half duplex compatibility.
0: PHY not able to perform 100BASE-X half duplex
1: PHY able to perform 100BASE-X half duplex
RO 1b
12 10BASE-T Full Duplex
This bit displays the status of 10BASE-T full duplex compatibility.
0: PHY not able to perform 10BASE-T full duplex
1: PHY able to perform 10BASE-T full duplex
RO 1b
11 10BASE-T Half Duplex
This bit displays the status of 10BASE-T half duplex compatibility.
0: PHY not able to perform 10BASE-T half duplex
1: PHY able to perform 10BASE-T half duplex
RO 1b
10 100BASE-T2 Full Duplex
This bit displays the status of 100BASE-T2 full duplex compatibility.
0: PHY not able to perform 100BASE-T2 full duplex
1: PHY able to perform 100BASE-T2 full duplex
RO 0b
Note 13.21
9100BASE-T2 Half Duplex
This bit displays the status of 100BASE-T2 half duplex compatibility.
0: PHY not able to perform 100BASE-T2 half duplex
1: PHY able to perform 100BASE-T2 half duplex
RO 0b
Note 13.21
8Extended Status
This bit displays whether extended status information is in register 15 (per
IEEE 802.3 clause 22.2.4).
0: No extended status information in Register 15
1: Extended status information in Register 15
RO 0b
Note 13.22
7RESERVED RO -
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Note 13.20 The reserved bits 31-16 are used to pad the register to 32-bits so that each register is on
a DWORD boundary. When accessed serially (through the MII management protocol), the
register is 16-bits wide.
Note 13.21 The Virtual PHY supports 100BASE-X (half and full duplex) and 10BASE-T (half and full
duplex) only. All other modes will always return as 0 (unable to perform).
Note 13.22 The Virtual PHY does not support Register 15 or 1000 Mb/s operation. Thus this bit is
always returned as 0.
Note 13.23 The Auto-Negotiation Complete bit is first cleared on a reset, but set shortly after (when
the Auto-Negotiation process is run). Refer to Section 7.3.1, "Virtual PHY Auto-
Negotiation," on page 110 for additional details.
Note 13.24 The Virtual PHY never has remote faults, its link is always up, and does not detect jabber.
Note 13.25 The VIrtual PHY supports basic and some extended register capability. The Virtual PHY
supports Registers 0-6 (per the IEEE 802.3 specification).
6MF Preamble Suppression
This bit indicates whether the Virtual PHY accepts management frames with
the preamble suppressed.
0: Management frames with preamble suppressed not accepted
1: Management frames with preamble suppressed accepted
RO 0b
5Auto-Negotiation Complete
This bit indicates the status of the Auto-Negotiation process.
0: Auto-Negotiation process not completed
1: Auto-Negotiation process completed
RO 1b
Note 13.23
4Remote Fault
This bit indicates if a remote fault condition has been detected.
0: No remote fault condition detected
1: Remote fault condition detected
RO 0b
Note 13.24
3Auto-Negotiation Ability
This bit indicates the status of the Virtual PHY’s auto-negotiation.
0: Virtual PHY is unable to perform auto-negotiation
1: Virtual PHY is able to perform auto-negotiation
RO 1b
2Link Status
This bit indicates the status of the link.
0: Link is down
1: Link is up
RO 1b
Note 13.24
1Jabber Detect
This bit indicates the status of the jabber condition.
0: No jabber condition detected
1: Jabber condition detected
RO 0b
Note 13.24
0Extended Capability
This bit indicates whether extended register capability is supported.
0: Basic register set capabilities only
1: Extended register set capabilities
RO 1b
Note 13.25
BITS DESCRIPTION TYPE DEFAULT
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13.2.6.3 Virtual PHY Identification MSB Register (VPHY_ID_MSB)
This read/write register contains the MSB of the Virtual PHY Organizationally Unique Identifier (OUI).
The LSB of the Virtual PHY OUI is contained in the Virtual PHY Identification LSB Register
(VPHY_ID_LSB).
Note 13.26 The reserved bits 31-16 are used to pad the register to 32-bits so that each register is on
a DWORD boundary. When accessed serially (through the MII management protocol), the
register is 16-bits wide.
Note 13.27 IEEE allows a value of zero in each of the 32-bits of the PHY Identifier.
Offset:
Index (decimal):
1C8h
2
Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED
(See Note 13.26)
RO -
15:0 PHY ID
This field contains the MSB of the Virtual PHY OUI (Note 13.27).
R/W 0000h
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13.2.6.4 Virtual PHY Identification LSB Register (VPHY_ID_LSB)
This read/write register contains the LSB of the Virtual PHY Organizationally Unique Identifier (OUI).
The MSB of the Virtual PHY OUI is contained in the Virtual PHY Identification MSB Register
(VPHY_ID_MSB).
Note 13.28 The reserved bits 31-16 are used to pad the register to 32-bits so that each register is on
a DWORD boundary. When accessed serially (through the MII management protocol), the
register is 16-bits wide.
Note 13.29 IEEE allows a value of zero in each of the 32-bits of the PHY Identifier.
Offset:
Index (decimal):
1CCh
3
Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED
(See Note 13.28)
RO -
15:10 PHY ID
This field contains the lower 6-bits of the Virtual PHY OUI (Note 13.29).
R/W 000000b
9:4 Model Number
This field contains the 6-bit manufacturer’s model number of the Virtual PHY
(Note 13.29).
R/W 000000b
3:0 Revision Number
This field contain the 4-bit manufacturer’s revision number of the Virtual PHY
(Note 13.29).
R/W 0000b
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13.2.6.5 Virtual PHY Auto-Negotiation Advertisement Register (VPHY_AN_ADV)
This read/write register contains the advertised ability of the Virtual PHY and is used in the Auto-
Negotiation process with the link partner.
Note: This register is re-written in its entirety by the EEPROM Loader following the release or reset
or a RELOAD command. Refer to Section 8.4, "EEPROM Loader," on page 121 for more
information.
Offset:
Index (decimal):
1D0h
4
Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED
(See Note 13.30)
RO -
15 Next Page
This bit determines the advertised next page capability and is always 0.
0: Virtual PHY does not advertise next page capability
1: Virtual PHY advertises next page capability
RO 0b
Note 13.31
14 RESERVED RO -
13 Remote Fault
This bit is not used since there is no physical link partner.
RO 0b
Note 13.32
12 RESERVED RO -
11 Asymmetric Pause
This bit determines the advertised asymmetric pause capability.
0: No Asymmetric PAUSE toward link partner advertised
1: Asymmetric PAUSE toward link partner advertised
R/W Note 13.33
10 Symmetric Pause
This bit determines the advertised symmetric pause capability.
0: No Symmetric PAUSE toward link partner advertised
1: Symmetric PAUSE toward link partner advertised
R/W Note 13.33
9100BASE-T4
This bit determines the advertised 100BASE-T4 capability and is always 0.
0: 100BASE-T4 ability not advertised
1: 100BASE-T4 ability advertised
RO 0b
Note 13.34
8100BASE-X Full Duplex
This bit determines the advertised 100BASE-X full duplex capability.
0: 100BASE-X full duplex ability not advertised
1: 100BASE-X full duplex ability advertised
R/W 1b
7100BASE-X Half Duplex
This bit determines the advertised 100BASE-X half duplex capability.
0: 100BASE-X half duplex ability not advertised
1: 100BASE-X half duplex ability advertised
R/W 1b
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Note 13.30 The reserved bits 31-16 are used to pad the register to 32-bits so that each register is on
a DWORD boundary. When accessed serially (through the MII management protocol), the
register is 16-bits wide.
Note 13.31 The Virtual PHY does not support next page capability. This bit value will always be 0.
Note 13.32 The Remote Fault bit is not useful since there is no actual link partner to send a fault to.
Note 13.33The Symmetric Pause and Asymmetric Pause bits default to 1 if the manual_FC_strap_0
strap is low (both Symmetric and Asymmetric are advertised), and 0 if the
manual_FC_strap_0 strap is high (neither Symmetric and Asymmetric are advertised).
Configuration strap values are latched upon the de-assertion of a chip-level reset as
described in Section 4.2.4, "Configuration Straps," on page 52.
Note 13.34 Virtual 100BASE-T4 is not supported.
Note 13.35 The Virtual PHY supports only IEEE 802.3. Only a value of 00001b should be used in this
field.
610BASE-T Full Duplex
This bit determines the advertised 10BASE-T full duplex capability.
0: 10BASE-T full duplex ability not advertised
1: 10BASE-T full duplex ability advertised
R/W 1b
510BASE-T Half Duplex
This bit determines the advertised 10BASE-T half duplex capability.
0: 10BASE-T half duplex ability not advertised
1: 10BASE-T half duplex ability advertised
R/W 1b
4:0 Selector Field
This field identifies the type of message being sent by Auto-Negotiation.
00001: IEEE 802.3
R/W 00001b
Note 13.35
BITS DESCRIPTION TYPE DEFAULT
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13.2.6.6 Virtual PHY Auto-Negotiation Link Partner Base Page Ability Register (VPHY_AN_LP_BASE_ABILITY)
This read-only register contains the advertised ability of the link partner’s PHY and is used in the Auto-
Negotiation process with the Virtual PHY. Because the Virtual PHY does not physically connect to an
actual link partner, the values in this register are emulated as described below.
Offset:
Index (decimal):
1D4h
5
Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED
(See Note 13.36)
RO -
15 Next Page
This bit indicates the emulated link partner PHY next page capability and is
always 0.
0: Link partner PHY does not advertise next page capability
1: Link partner PHY advertises next page capability
RO 0b
Note 13.37
14 Acknowledge
This bit indicates whether the link code word has been received from the
partner and is always 1.
0: Link code word not yet received from partner
1: Link code word received from partner
RO 1b
Note 13.37
13 Remote Fault
Since there is no physical link partner, this bit is not used and is always
returned as 0.
RO 0b
Note 13.37
12 RESERVED RO -
11 Asymmetric Pause
This bit indicates the emulated link partner PHY asymmetric pause
capability.
0: No Asymmetric PAUSE toward link partner
1: Asymmetric PAUSE toward link partner
RO Note 13.38
10 Pause
This bit indicates the emulated link partner PHY symmetric pause capability.
0: No Symmetric PAUSE toward link partner
1: Symmetric PAUSE toward link partner
RO Note 13.38
9100BASE-T4
This bit indicates the emulated link partner PHY 100BASE-T4 capability.
This bit is always 0.
0: 100BASE-T4 ability not supported
1: 100BASE-T4 ability supported
RO 0b
Note 13.37
8100BASE-X Full Duplex
This bit indicates the emulated link partner PHY 100BASE-X full duplex
capability.
0: 100BASE-X full duplex ability not supported
1: 100BASE-X full duplex ability supported
RO Note 13.39
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Note 13.36 The reserved bits 31-16 are used to pad the register to 32-bits so that each register is on
a DWORD boundary. When accessed serially (through the MII management protocol), the
register is 16-bits wide.
Note 13.37 The emulated link partner does not support next page, always instantly sends its link code
word, never sends a fault, and does not support 100BASE-T4.
Note 13.38 The emulated link partner’s asymmetric/symmetric pause ability is based upon the values
of the Asymmetric Pause and Symmetric Pause bits of the Virtual PHY Auto-Negotiation
Advertisement Register (VPHY_AN_ADV). Thus the emulated link partner always
accommodates the request of the Virtual PHY, as shown in Ta b l e 1 3 .6.
The link partner pause ability bits are determined when Auto-Negotiation is complete.
Changing the Virtual PHY Auto-Negotiation Advertisement Register (VPHY_AN_ADV) will
have no affect until the Auto-Negotiation process is re-run. If the local device advertises
both Symmetric and Asymmetric pause, the result is determined based on the
FD_FC_strap_0 configuration strap. This allows the user the choice of network emulation.
If FD_FC_strap_0 = 1, then the result is Symmetrical, else Asymmetrical. See Section
7.3.1, "Virtual PHY Auto-Negotiation," on page 110 for additional information.
7100BASE-X Half Duplex
This bit indicates the emulated link partner PHY 100BASE-X half duplex
capability.
0: 100BASE-X half duplex ability not supported
1: 100BASE-X half duplex ability supported
RO Note 13.39
610BASE-T Full Duplex
This bit indicates the emulated link partner PHY 10BASE-T full duplex
capability.
0: 10BASE-T full duplex ability not supported
1: 10BASE-T full duplex ability supported
RO Note 13.39
510BASE-T Half Duplex
This bit indicates the emulated link partner PHY 10BASE-T half duplex
capability.
0: 10BASE-T half duplex ability not supported
1: 10BASE-T half duplex ability supported
RO Note 13.39
4:0 Selector Field
This field identifies the type of message being sent by Auto-Negotiation.
00001: IEEE 802.3
RO 00001b
Table 13.6 Emulated Link Partner Pause Flow Control Ability Default Values
VPHY
SYMMETRIC
PAUSE
(REGISTER 4.10)
VPHY
ASYMMETRIC
PAUSE
(REGISTER 4.11) FD_FC_strap_0
LINK PARTNER
SYMMETRIC
PAUSE
(REGISTER 5.10)
LINK PARTNER
ASYMMETRIC
PAUSE
(REGISTER 5.11)
No Flow Control Enabled 0 0 x 0 0
Symmetric Pause 1 0 x 1 0
Asymmetric Pause
Towards Switch
01x11
BITS DESCRIPTION TYPE DEFAULT
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Note 13.39 The emulated link partner’s ability is based on the P0_DUPLEX pin, duplex_pol_strap_0,
and speed_strap_0, as well as on the Auto-Negotiation success. Table 13.7 defines the
default capabilities of the emulated link partner as a function of these signals. Configuration
strap values are latched upon the de-assertion of a chip-level reset as described in Section
4.2.4, "Configuration Straps," on page 52. For more information on the Virtual PHY auto-
negotiation, see Section 7.3.1, "Virtual PHY Auto-Negotiation," on page 110.
Asymmetric Pause
Toward s M A C
11001
Symmetric Pause11111
Table 13.7 Emulated Link Partner Default Advertised Ability
speed_strap_0
ADVERTISED LINK PARTNER ABILITY
(BITS 8,7,6,5)
P0_DUPLEX =
duplex_pol_strap_0
0 10BASE-T Full-Duplex (0010)
1 100BASE-X Full-Duplex (1000)
P0_DUPLEX !=
duplex_pol_strap_0
0 10BASE-T Half-Duplex (0001)
1 100BASE-X Half-Duplex (0100)
Table 13.6 Emulated Link Partner Pause Flow Control Ability Default Values
VPHY
SYMMETRIC
PAUSE
(REGISTER 4.10)
VPHY
ASYMMETRIC
PAUSE
(REGISTER 4.11) FD_FC_strap_0
LINK PARTNER
SYMMETRIC
PAUSE
(REGISTER 5.10)
LINK PARTNER
ASYMMETRIC
PAUSE
(REGISTER 5.11)
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13.2.6.7 Virtual PHY Auto-Negotiation Expansion Register (VPHY_AN_EXP)
This register is used in the Auto-Negotiation process.
Note 13.40 The reserved bits 31-16 are used to pad the register to 32-bits so that each register is on
a DWORD boundary. When accessed serially (through the MII management protocol), the
register is 16-bits wide.
Note 13.41 Since the Virtual PHY link partner is emulated, there is never a Parallel Detection Fault
and this bit is always 0.
Note 13.42 Next page ability is not supported by the Virtual PHY or emulated link partner.
Note 13.43 The Page Received bit is clear when read. It is first cleared on reset, but set shortly
thereafter when the Auto-Negotiation process is run.
Note 13.44 The emulated link partner will show Auto-Negotiation able unless Auto-Negotiation fails (no
common bits between the advertised ability and the link partner ability).
Offset:
Index (decimal):
1D8h
6
Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED
(See Note 13.40)
RO -
15:5 RESERVED RO -
4Parallel Detection Fault
This bit indicates whether a Parallel Detection Fault has been detected. This
bit is always 0.
0: A fault hasn’t been detected via the Parallel Detection function
1: A fault has been detected via the Parallel Detection function
RO 0b
Note 13.41
3Link Partner Next Page Able
This bit indicates whether the link partner has next page ability. This bit is
always 0.
0: Link partner does not contain next page capability
1: Link partner contains next page capability
RO 0b
Note 13.42
2Local Device Next Page Able
This bit indicates whether the local device has next page ability. This bit is
always 0.
0: Local device does not contain next page capability
1: Local device contains next page capability
RO 0b
Note 13.42
1Page Received
This bit indicates the reception of a new page.
0: A new page has not been received
1: A new page has been received
RO/LH 1b
Note 13.43
0Link Partner Auto-Negotiation Able
This bit indicates the Auto-negotiation ability of the link partner.
0: Link partner is not Auto-Negotiation able
1: Link partner is Auto-Negotiation able
RO 1b
Note 13.44
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13.2.6.8 Virtual PHY Special Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS)
This read/write register contains a current link speed/duplex indicator and SQE control.
Offset:
Index (decimal):
1DCh
31
Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED
(See Note 13.45)
RO -
15 RESERVED RO -
14 Switch Looopback Port 0
When set, transmissions from the Switch Fabric Port 0 are not sent to the
External MAC. Instead, they are looped back into the Switch Engine.
From the MAC viewpoint, this is effectively a FAR LOOPBACK.
If loopback is enabled during half-duplex operation, then the Enable Receive
Own Transmit bit in the Port x MAC Receive Configuration Register
(MAC_RX_CFG_x) must be set for this port. Otherwise, the Switch Fabric
will ignore receive activity when transmitting in half-duplex mode.
Note: This mode works even if the Isolate (VPHY_ISO) bit of the Virtual
PHY Basic Control Register (VPHY_BASIC_CTRL) is set.
R/W 0b
13:11 RESERVED RO -
10 Turbo MII Enable
When set, this bit changes the data rate of the MII PHY 100Mbps mode to
200Mbps. The normal Virtual PHY selection mechanism that chooses
between 10 and 100Mbps will instead choose between 10Mbps and
200Mbps.
Note: When operating at 200Mbps, the drive strength of the MII output
clocks is selected using the RMII/Turbo MII Clock Strength bit.
When at 100 Mbps or 10 Mbps, the drive strength is fixed at 12
mA.
R/W Note 13.46
9:8 Mode
This field indicates the operating mode of port 0.
00: MII MAC mode
01: MII PHY mode
10: RMII PHY mode
11: RESERVED
RO Note 13.47
7Switch Collision Test Port 0
When set, the collision signal to the Switch Fabric Port 0 is active during
transmission from the Switch Engine.
Note: It is recommended that this bit be used only when using loopback
mode.
R/W 0b
6RMII Clock Direction
0: Selects P0_OUTCLK as an Input
1: Selects P0_OUTCLK as an Output
R/W
NASR
Note 13.51
Note 13.48
5RMII/Turbo MII Clock Strength
For RMII and 200 Mbps MII PHY modes, a low selects 12 mA drive while a
high selects a 16 mA drive. For 100 Mbps and 10 Mbps MII PHY modes,
the drive strength is fixed at 12mA.
R/W
NASR
Note 13.51
Note 13.49
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Note 13.45 The reserved bits 31-16 are used to pad the register to 32-bits so that each register is on
a DWORD boundary. When accessed serially (through the MII management protocol), the
register is 16-bits wide.
Note 13.46 The default value of this field is determined via the turbo_mii_enable_strap_0 configuration
strap. Refer to Section 4.2.4, "Configuration Straps," on page 52 for additional information.
Note 13.47 The default value of this field is determined via the P0_mode_strap[1:0] configuration
straps. Refer to Section 4.2.4, "Configuration Straps," on page 52 for additional
information.
Note 13.48 The default value of this field is determined via the P0_rmii_clock_dir_strap configuration
strap. Refer to Section 4.2.4, "Configuration Straps," on page 52 for additional information.
Note 13.49 The default value of this field is determined via the P0_clock_strength_strap configuration
strap. Refer to Section 4.2.4, "Configuration Straps," on page 52 for additional information.
Note 13.50 The default value of this field is the result of the Auto-Negotiation process if the Auto-
Negotiation (VPHY_AN) bit of the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL) is set. Otherwise, this field reflects the Speed Select LSB
(VPHY_SPEED_SEL_LSB) and Duplex Mode (VPHY_DUPLEX) bit settings of the
VPHY_BASIC_CTRL register. Refer to Section 7.3.1, "Virtual PHY Auto-Negotiation," on
page 110 for information on the Auto-Negotiation determination process of the Virtual PHY.
Note 13.51 Register bits designated as NASR are reset when the Virtual PHY Reset is generated via
the Reset Control Register (RESET_CTL). The NASR designation is only applicable when
the Reset (VPHY_RST) bit of the Virtual PHY Basic Control Register
(VPHY_BASIC_CTRL) is set.
Note 13.52 The default value of this field is determined via the SQE_test_disable_strap_0
configuration strap. Refer to Section 4.2.4, "Configuration Straps," on page 52 for
additional information.
4:2 Current Speed/Duplex Indication
This field indicates the current speed and duplex of the Virtual PHY link.
RO Note 13.50
1RESERVED RO -
0SQEOFF
This bit enables/disables the Signal Quality Error (Heartbeat) test.
0: SQE test enabled
1: SQE test disabled
Note: This bit is used when Port 0 is in MII PHY mode. It is not usable
in RMII PHY or MII MAC modes.
R/W
NASR
Note 13.51
Note 13.52
BITS DESCRIPTION TYPE DEFAULT
[4] [3] [2] Speed Duplex
0 0 0 RESERVED
0 0 1 10Mbps half-duplex
0 1 0 100/200Mbps half-duplex
0 1 1 RESERVED
1 0 0 RESERVED
1 0 1 10Mbps full-duplex
1 1 0 100/200Mbps full-duplex
1 1 1 RESERVED
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13.2.7 Miscellaneous
This section details the remainder of the System CSR’s. These registers allow for monitoring and
configuration of various functions such as the Chip ID/revision, byte order testing, hardware
configuration, general purpose timer, and free running counter.
13.2.7.1 Chip ID and Revision (ID_REV)
This read-only register contains the ID and Revision fields for the device.
Note 13.53 Default value is dependent on device revision.
Offset: 050h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 Chip ID
This field indicates the chip ID.
RO 9303h
15:0 Chip Revision
This field indicates the design revision.
RO Note 13.53
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13.2.7.2 Byte Order Test Register (BYTE_TEST)
This read-only register can be used to determine the byte ordering of the current configuration.
Note: This register can be read while the device is in the not ready state. This register can also be
polled while the device is in the reset state without causing any damaging effects. The returned
data will be invalid since the serial interfaces are also in the reset state at this time. However,
the returned data will not match the normal valid data pattern during reset.
Note: In SMI mode, either half of this register can be read without the need to read the other half.
Offset: 064h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Byte Test (BYTE_TEST)
This field reflects the current byte ordering
RO 87654321h
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13.2.7.3 Hardware Configuration Register (HW_CFG)
This register allows the configuration of various hardware features.
Note: This register can be polled while the device is in the reset or not ready state (Device Ready
(READY) bit is cleared). Returned data will be invalid during the reset state since the serial
interfaces are also in reset at this time.
Note: In SMI mode, either half of this register can be read without the need to read the other half.
Note 13.54 The default value of this field is determined by the configuration strap auto_mdix_strap_2.
See Section 4.2.4, "Configuration Straps," on page 52 for more information.
Note 13.55 The default value of this field is determined by the configuration strap auto_mdix_strap_1.
See Section 4.2.4, "Configuration Straps," on page 52 for more information.
Offset: 074h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:28 RESERVED RO -
27 Device Ready (READY)
When set, this bit indicates that the device is ready to be accessed. Upon
power-up, nRST reset, or digital reset, the host processor may interrogate
this field as an indication that the device has stabilized and is fully active.
This bit can cause an interrupt if enabled.
Note: With the exception of the HW_CFG, BYTE_TEST, and
RESET_CTL registers, read access to any internal resources is
forbidden while the READY bit is cleared. Writes to any address
are invalid until this bit is set.
RO 0b
26 AMDIX_EN Strap State Port 2
This bit reflects the state of the auto_mdix_strap_2 strap that connects to
the PHY. The strap value is loaded with the level of the auto_mdix_strap_2
during reset and can be re-written by the EEPROM Loader. The strap value
can be overridden by the Auto-MDIX Control (AMDIXCTRL) and Auto-MDIX
State (AMDIXSTATE) bits of the Port 2 PHY Special Control/Status
Indication Register (Section 13.3.2.10).
RO Note 13.54
25 AMDIX_EN Strap State Port 1
This bit reflects the state of the auto_mdix_strap_1 strap that connects to
the PHY. The strap value is loaded with the level of the auto_mdix_strap_1
during reset and can be re-written by the EEPROM Loader. The strap value
can be overridden by the Auto-MDIX Control (AMDIXCTRL) and Auto-MDIX
State (AMDIXSTATE) bits of the Port 1 PHY Special Control/Status
Indication Register (Section 13.3.2.10).
RO Note 13.55
24:0 RESERVED RO -
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13.2.7.4 General Purpose Timer Configuration Register (GPT_CFG)
This read/write register configures the General Purpose Timer (GPT). The GPT can be configured to
generate host interrupts at the interval defined in this register. The current value of the GPT can be
monitored via the General Purpose Timer Count Register (GPT_CNT). Refer to Section 11.1, "General
Purpose Timer," on page 143 for additional information.
Offset: 08Ch Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:30 RESERVED RO -
29 General Purpose Timer Enable (TIMER_EN)
This bit enables the GPT. When set, the GPT enters the run state. When
cleared, the GPT is halted. On the 1 to 0 transition of this bit, the
GPT_LOAD field of this register will be preset to FFFFh.
0: GPT Disabled
1: GPT Enabled
R/W 0b
28:16 RESERVED RO -
15:0 General Purpose Timer Pre-Load (GPT_LOAD)
This value is pre-loaded into the GPT. This is the starting value of the GPT.
The timer will begin decrementing from this value when enabled.
R/W FFFFh
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13.2.7.5 General Purpose Timer Count Register (GPT_CNT)
This read-only register reflects the current general purpose timer (GPT) value. The register should be
used in conjunction with the General Purpose Timer Configuration Register (GPT_CFG) to configure
and monitor the GPT. Refer to Section 11.1, "General Purpose Timer," on page 143 for additional
information.
Offset: 090h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED RO -
15:0 General Purpose Timer Current Count (GPT_CNT)
This 16-bit field represents the current value of the GPT.
RO FFFFh
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13.2.7.6 Free Running 25MHz Counter Register (FREE_RUN)
This read-only register reflects the current value of the free-running 25MHz counter. Refer to Section
11.2, "Free-Running Clock," on page 143 for additional information.
Offset: 09Ch Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Free Running Counter (FR_CNT)
This field reflects the current value of the free-running 32-bit counter. At
reset, the counter starts at zero and is incremented by one every 25MHz
cycle. When the maximum count has been reached, the counter will rollover
to zero and continue counting.
Note: The free running counter can take up to 160nS to clear after a reset
event.
RO 00000000h
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13.2.7.7 Port 1 MII Basic Control Register (P1_MII_BASIC_CONTROL)
This register is re-written in its entirety by the EEPROM Loader following the release of reset or a
RELOAD command. Refer to Section 8.4, "EEPROM Loader," on page 121 for additional information.
Offset: 1ECh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31 RESERVED RO -
30 Switch Looopback Port 1
When set, transmissions from the Switch Fabric Port 1 are not sent to the
External MAC. Instead, they are looped back into the Switch Engine.
From the MAC viewpoint, this is effectively a FAR LOOPBACK.
If loopback is enabled during half-duplex operation, then the Enable Receive
Own Transmit bit in the (x=1) Port x MAC Receive Configuration Register
(MAC_RX_CFG_x) must be set for this port. Otherwise, the Switch Fabric
will ignore receive activity when transmitting in half-duplex mode.
Note: This mode works even if the Isolate bit is set.
Note: This bit is used when Port 1 is in MII or RMII PHY mode. It is not
usable in internal PHY or MII MAC modes.
R/W 0b
29 RESERVED RO -
28 Manual Duplex
When set, the duplex is based on the Duplex Mode bit. When clear, the
duplex is based on the P1_DUPLEX input and duplex_pol_strap_1.
Note: This bit is used when Port 1 is in the MII MAC mode. It is not
usable in internal PHY or MII or RMII PHY modes.
R/W 0b
27 RESERVED RO -
26 Turbo MII Enable
This bit, along with the Speed Select LSB bit, determines the speed of the
MII PHY mode.
When set, the Speed Select LSB bit selects between 200Mbps and 10
Mbps. When cleared, the Speed Select LSB bit selects between 100Mbps
and 10 Mbps.
Note: When operating at 200Mbps, the drive strength of the MII output
clock is selected using the RMII/Turbo MII Clock Strength bit. When
at 100 Mbps or 10 Mbps, the drive strength is fixed at 12 mA.
R/W Note 13.56
25:24 Mode
This field indicates the operating mode of port 1.
00: MII MAC mode
01: MII PHY mode
10: RMII PHY mode
11: Internal PHY mode
RO Note 13.57
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23 Switch Collision Test Port 1
When set, the collision signal to the Switch Fabric Port 1 is active during
transmission from the Switch Engine.
Note: This bit is used when Port 1 is in the MII or RMII PHY mode. It is
not usable in the internal PHY or MII MAC modes.
Note: It is recommended that this bit be used only when using loopback
mode.
R/W 0b
22 RMII Clock Direction
0: Selects P1_OUTCLK as an Input
1: Selects P1_OUTCLK as an Output
R/W Note 13.58
21 RMII/Turbo MII Clock Strength
For RMII and 200 Mbps MII PHY modes, a low selects 12 mA drive while a
high selects a 16 mA drive. For 100 Mbps and 10 Mbps MII PHY modes,
the drive strength is fixed at 12mA.
R/W Note 13.59
20:17 RESERVED RO -
16 SQEOFF
This bit enables/disables the Signal Quality Error (Heartbeat) test.
0: SQE test enabled
1: SQE test disabled
Note: This bit is used when Port 1 is in MII PHY mode. It is not usable
in internal PHY, RMII PHY, or MII MAC modes.
R/W Note 13.60
15 RESERVED RO -
14 Loopback
When set, transmissions from the external MAC are not sent to the Switch
Engine. Instead, they are looped back onto the receive path.
Note: This bit is used when Port 1 is in MII or RMII PHY mode. It is not
usable in internal PHY or MII MAC modes.
R/W 0b
13 Speed Select LSB
This bit is used, along with the Turbo MII Enable bit, to set the speed.
0: 10 Mbps
1: 200 or 100 Mbps
Note: This bit is used when Port 1 is in MII or RMII PHY mode. It is not
usable in internal PHY or MII MAC modes.
R/W Note 13.61
12:11 RESERVED RO -
10 Isolate
When set and in PHY mode, the MII output pins are not driven, the MII pull-
ups and pull-downs are disabled, and the input pins are ignored.
Note: This bit is used when Port 1 is in MII or RMII PHY mode. It is not
usable in internal PHY or MII MAC modes.
R/W 0b
9RESERVED RO -
8Duplex Mode
In MII and RMII PHY modes, this bit is used to set the duplex. In MII MAC
mode, this bit is used to set the duplex when the Manual Duplex bit is set.
0: Half duplex
1: Full duplex
Note: This bit is used when Port 1 is in MII PHY, RMII PHY, or MII MAC
mode. It is not usable in internal PHY mode.
R/W Note 13.62
BITS DESCRIPTION TYPE DEFAULT
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Note 13.56 The default value of this field is determined via the turbo_mii_enable_strap_1 configuration
strap. Refer to Section 4.2.4, "Configuration Straps," on page 52 for additional information.
Note 13.57 The default value of this field is determined via the P1_mode_strap[1:0] configuration
straps. Refer to Section 4.2.4, "Configuration Straps," on page 52 for additional
information.
Note 13.58 The default value of this field is determined via the P1_rmii_clock_dir_strap configuration
strap. Refer to Section 4.2.4, "Configuration Straps," on page 52 for additional information.
Note 13.59 The default value of this field is determined via the P1_clock_strength_strap configuration
strap. Refer to Section 4.2.4, "Configuration Straps," on page 52 for additional information.
Note 13.60 The default value of this field is determined via the SQE_test_disable_strap_1
configuration strap. Refer to Section 4.2.4, "Configuration Straps," on page 52 for
additional information.
Note 13.61 The default value of this field is determined via the speed_strap_1 configuration strap.
Refer to Section 4.2.4, "Configuration Straps," on page 52 for additional information.
Note 13.62 The default value of this field is determined as follows:
1 if duplex_pol_strap_1 = P1_DUPLEX
0 if duplex_pol_strap_1 != P1_DUPLEX.
7Collision Test
This bit enables/disables the collision test mode. When set, the collision
signal to the external MAC is active during transmission from the external
MAC.
Note: It is recommended that this bit be used only when in loopback
mode.
0: Collision test mode disabled
1: Collision test mode enabled
Note: This bit is used when Port 1 is in MII PHY mode. It is not usable
in internal PHY, RMII PHY, or MII MAC mode.
R/W 0b
6:0 RESERVED RO -
BITS DESCRIPTION TYPE DEFAULT
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13.2.7.8 Reset Control Register (RESET_CTL)
This register contains software controlled resets.
Note: This register can be read while the device is in the not ready state. This register can also be
polled while the device is in the reset state without causing any damaging effects. However,
the returned data will be invalid since the serial interfaces are also in the reset state at this
time.
Note: In SMI mode, either half of this register can be read without the need to read the other half.
Offset: 1F8h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:4 RESERVED RO -
3Virtual PHY Reset (VPHY_RST)
Setting this bit resets the Virtual PHY. When the Virtual PHY is released from
reset, this bit is automatically cleared. All writes to this bit are ignored while
this bit is set.
Note: This bit is not accessible via the EEPROM Loader.
R/W
SC
0b
2Port 2 PHY Reset (PHY2_RST)
Setting this bit resets the Port 2 PHY. The internal logic automatically holds
the PHY reset for a minimum of 102uS. When the Port 2 PHY is released
from reset, this bit is automatically cleared. All writes to this bit are ignored
while this bit is set.
Note: This bit is not accessible via the EEPROM Loader.
R/W
SC
0b
1Port 1 PHY Reset (PHY1_RST)
Setting this bit resets the Port 1 PHY. The internal logic automatically holds
the PHY reset for a minimum of 102uS. When the Port 1 PHY is released
from reset, this bit is automatically cleared. All writes to this bit are ignored
while this bit is set.
Note: This bit is not accessible via the EEPROM Loader.
R/W
SC
0b
0Digital Reset (DIGITAL_RST)
Setting this bit resets the complete chip except the PLL, Virtual PHY, Port 1
PHY, and Port 2 PHY. The EEPROM Loader will automatically reload the
configuration following this reset, but will not reset the Virtual PHY, Port 1
PHY, or Port 2 PHY. If desired, the above PHY resets can be issued once
the device is configured. All system CSRs are reset except for any NASR
type bits. Any in progress EEPROM commands (including RELOAD) are
terminated.
When the chip is released from reset, this bit is automatically cleared. The
Byte Order Test Register (BYTE_TEST) should be polled to determine when
the reset is complete. All writes to this bit are ignored while this bit is set.
Note: This bit is not accessible via the EEPROM Loader.
R/W
SC
0b
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13.3 Ethernet PHY Control and Status Registers
This section details the various Ethernet PHY control and status registers. The device contains three
PHY’s: Port 1 PHY, Port 2 PHY and a Virtual PHY. All PHY registers follow the IEEE 802.3 (clause
22.2.4) specified MII management register set. All functionality and bit definitions comply with these
standards. The IEEE 802.3 specified register index (in decimal) is included with each register definition,
allowing for addressing of these registers via the MII serial management protocol. For additional
information on the MII management protocol, refer to the IEEE 802.3 Specification.
Each individual PHY is assigned a unique PHY address as detailed in Section 7.1.1, "PHY
Addressing," on page 96.
13.3.1 Virtual PHY Registers
The Virtual PHY provides a basic MII management interface for communication with an standard
external MAC as if it was attached to a single port PHY. The Virtual PHY registers differ from the Port
1 & 2 PHY registers in that they are addressable via the memory map, as described in Table 13.2, as
well as serially. These modes of access are described in Section 13.2.6, "Virtual PHY," on page 181.
Because the Virtual PHY registers are also memory mapped, their definitions have been included in
the System Control and Status Registers Section 13.2.6, "Virtual PHY," on page 181. A list of the Virtual
PHY MII addressable registers and their corresponding register index numbers is also included in
Table 13.5.
Note: When serially accessed, the Virtual PHY registers are only 16-bits wide, as is standard for MII
management of PHY’s.
13.3.2 Port 1 & 2 PHY Registers
The Port 1 and Port 2 PHY’s are comparable in functionality and have an identical set of non-memory
mapped registers. The Port 1 and Port 2 PHY registers are not memory mapped. These registers are
indirectly accessed through the PHY Management Interface Access Register (PMI_ACCESS) and PHY
Management Interface Data Register (PMI_DATA) registers (in MAC or PHY I2C modes only) or
through the MII management pins (in MAC or PHY SMI modes only) via the MII serial management
protocol specified in IEEE 802.3 clause 22. See Section 2.3, "Modes of Operation," on page 19 for a
details on the various device modes. Because the Port 1 & 2 PHY registers are functionally identical,
their register descriptions have been consolidated. A lowercase “x” has been appended to the end of
each PHY register name in this section, where “x” should be replaced with “1” or “2” for the Port 1
PHY or the Port 2 PHY registers respectively. A list of the Port 1 & 2 PHY MII addressable registers
and their corresponding register index numbers is included in Table 13.8. Each individual PHY is
assigned a unique PHY address as detailed in Section 7.1.1, "PHY Addressing," on page 96.
Table 13.8 Port 1 & 2 PHY MII Serially Adressable Registers
INDEX # SYMBOL REGISTER NAME
0 PHY_BASIC_CONTROL_x Port x PHY Basic Control Register, Section 13.3.2.1
1 PHY_BASIC_STATUS_x Port x PHY Basic Status Register, Section 13.3.2.2
2 PHY_ID_MSB_x Port x PHY Identification MSB Register, Section 13.3.2.3
3 PHY_ID_LSB_x Port x PHY Identification LSB Register, Section 13.3.2.4
4 PHY_AN_ADV_x Port x PHY Auto-Negotiation Advertisement Register,
Section 13.3.2.5
5PHY_AN_LP_BASE_ABILITY_x Port x PHY Auto-Negotiation Link Partner Base Page Ability
Register, Section 13.3.2.6
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6 PHY_AN_EXP_x Port x PHY Auto-Negotiation Expansion Register,
Section 13.3.2.7
17 PHY_MODE_CONTROL_STATUS_x Port x PHY Mode Control/Status Register, Section 13.3.2.8
18 PHY_SPECIAL_MODES_x Port x PHY Special Modes Register, Section 13.3.2.9
27 PHY_SPECIAL_CONTROL_STAT_IND_x Port x PHY Special Control/Status Indication Register,
Section 13.3.2.10
29 PHY_INTERRUPT_SOURCE_x Port x PHY Interrupt Source Flags Register, Section 13.3.2.11
30 PHY_INTERRUPT_MASK_x Port x PHY Interrupt Mask Register, Section 13.3.2.12
31 PHY_SPECIAL_CONTROL_STATUS_x Port x PHY Special Control/Status Register, Section 13.3.2.13
Table 13.8 Port 1 & 2 PHY MII Serially Adressable Registers (continued)
INDEX # SYMBOL REGISTER NAME
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13.3.2.1 Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x)
This read/write register is used to configure the Port x PHY.
Note: This register is re-written in its entirety by the EEPROM Loader following the release of reset
or a RELOAD command. Refer to Section 8.4, "EEPROM Loader," on page 121 for additional
information.
Index (decimal): 0 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15 Reset (PHY_RST)
When set, this bit resets all the Port x PHY registers to their default state,
except those marked as NASR type. This bit is self clearing.
0: Normal operation
1: Reset
R/W
SC
0b
14 Loopback (PHY_LOOPBACK)
This bit enables/disables the loopback mode. When enabled, transmissions
from the Switch Fabric are not sent to network. Instead, they are looped
back into the Switch Fabric.
Note: If loopback is enabled during half-duplex operation, then the
Enable Receive Own Transmit bit in the Port x MAC Receive
Configuration Register (MAC_RX_CFG_x) must be set for the
specified port. Otherwise, the Switch Fabric will ignore receive
activity when transmitting in half-duplex mode.
0: Loopback mode disabled (normal operation)
1: Loopback mode enabled
R/W 0b
13 Speed Select LSB (PHY_SPEED_SEL_LSB)
This bit is used to set the speed of the Port x PHY when the Auto-
Negotiation (PHY_AN) bit is disabled.
0: 10 Mbps
1: 100 Mbps
R/W Note 13.63
12 Auto-Negotiation (PHY_AN)
This bit enables/disables Auto-Negotiation. When enabled, the Speed Select
LSB (PHY_SPEED_SEL_LSB) and Duplex Mode (PHY_DUPLEX) bits are
overridden.
0: Auto-Negotiation disabled
1: Auto-Negotiation enabled
R/W Note 13.64
11 Power Down (PHY_PWR_DWN)
This bit controls the power down mode of the Port x PHY. After this bit is
cleared the PHY may auto-negotiate with it’s partner station. This process
can take up to a few seconds to complete. Once Auto-Negotiation is
complete, the Auto-Negotiation Complete bit of the Port x PHY Basic Status
Register (PHY_BASIC_STATUS_x) will be set.
Note: The PHY_AN bit of this register must be cleared before setting this
bit.
0: Normal operation
1: General power down mode
R/W 0b
10 RESERVED RO -
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Note 13.63 For Port 1 operating in an external mode (MII PHY, RMII PHY, or MII MAC mode), the
default value of this bit is 1 and is independent of any strap. For Port 1 operating in Internal
PHY mode and for all operating modes of Port 2, the default value of this bit is determined
by the logical OR of the Auto-Negotiation strap (autoneg_strap_1 for Port 1 PHY,
autoneg_strap_2 for Port 2 PHY) and the Speed Select strap (speed_strap_1 for Port 1
PHY, speed_strap_2 for Port 2 PHY). Essentially, if the Auto-Negotiation strap is set, the
default value is 1, otherwise the default is determined by the value of the Speed Select
strap. Refer to Section 4.2.4, "Configuration Straps," on page 52 for more information.
Note 13.64 For Port 1 operating in an external mode (MII PHY, RMII PHY, or MII MAC mode), the
default value of this bit is 0 and is independent of any strap. For Port 1 operating in Internal
PHY mode and for all operating modes of Port 2, the default value of this bit is the value
of the Auto-Negotiation strap (autoneg_strap_1 for Port 1 PHY, autoneg_strap_2 for Port
2 PHY). Refer to Section 4.2.4, "Configuration Straps," on page 52 for more information.
Note 13.65 For Port 1 operating in an external mode (MII PHY, RMII PHY, or MII MAC mode), the
default value of this bit is 0 and is independent of any strap. For Port 1 operating in Internal
PHY mode and for all operating modes of Port 2, the default value of this bit is determined
by the logical AND of the negation of the Auto-Negotiation strap (autoneg_strap_1 for Port
1 PHY, autoneg_strap_2 for Port 2 PHY) and the Duplex Select strap (duplex_strap_1 for
Port 1 PHY, duplex_strap_2 for Port 2 PHY). Essentially, if the Auto-Negotiation strap is
set, the default value is 0, otherwise the default is determined by the value of the Duplex
Select strap. Refer to Section 4.2.4, "Configuration Straps," on page 52 for more
information.
9Restart Auto-Negotiation (PHY_RST_AN)
When set, this bit restarts the Auto-Negotiation process.
0: Normal operation
1: Auto-Negotiation restarted
R/W
SC
0b
8Duplex Mode (PHY_DUPLEX)
This bit is used to set the duplex when the Auto-Negotiation (PHY_AN) bit
is disabled.
0: Half Duplex
1: Full Duplex
R/W Note 13.65
7Collision Test Mode (PHY_COL_TEST)
This bit enables/disables the collision test mode of the Port x PHY. When
set, the collision signal is active during transmission. It is recommended that
this feature be used only in loopback mode.
0: Collision test mode disabled
1: Collision test mode enabled
R/W 0b
6:0 RESERVED RO -
BITS DESCRIPTION TYPE DEFAULT
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13.3.2.2 Port x PHY Basic Status Register (PHY_BASIC_STATUS_x)
This register is used to monitor the status of the Port x PHY.
Index (decimal): 1 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15 100BASE-T4
This bit displays the status of 100BASE-T4 compatibility.
0: PHY not able to perform 100BASE-T4
1: PHY able to perform 100BASE-T4
RO 0b
Note 13.66
14 100BASE-X Full Duplex
This bit displays the status of 100BASE-X full duplex compatibility.
0: PHY not able to perform 100BASE-X full duplex
1: PHY able to perform 100BASE-X full duplex
RO 1b
13 100BASE-X Half Duplex
This bit displays the status of 100BASE-X half duplex compatibility.
0: PHY not able to perform 100BASE-X half duplex
1: PHY able to perform 100BASE-X half duplex
RO 1b
12 10BASE-T Full Duplex
This bit displays the status of 10BASE-T full duplex compatibility.
0: PHY not able to perform 10BASE-T full duplex
1: PHY able to perform 10BASE-T full duplex
RO 1b
11 10BASE-T Half Duplex
This bit displays the status of 10BASE-T half duplex compatibility.
0: PHY not able to perform 10BASE-T half duplex
1: PHY able to perform 10BASE-T half duplex
RO 1b
10 100BASE-T2 Full Duplex
This bit displays the status of 100BASE-T2 full duplex compatibility.
0: PHY not able to perform 100BASE-T2 full duplex
1: PHY able to perform 100BASE-T2 full duplex
RO 0b
Note 13.66
9100BASE-T2 Half Duplex
This bit displays the status of 100BASE-T2 half duplex compatibility.
0: PHY not able to perform 100BASE-T2 half duplex
1: PHY able to perform 100BASE-T2 half duplex
RO 0b
Note 13.66
8:6 RESERVED RO -
5Auto-Negotiation Complete
This bit indicates the status of the Auto-Negotiation process.
0: Auto-Negotiation process not completed
1: Auto-Negotiation process completed
RO 0b
4Remote Fault
This bit indicates if a remote fault condition has been detected.
0: No remote fault condition detected
1: Remote fault condition detected
RO/LH 0b
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Note 13.66 The PHY supports 100BASE-TX (half and full duplex) and 10BASE-T (half and full duplex)
only. All other modes will always return as 0 (unable to perform).
3Auto-Negotiation Ability
This bit indicates the status of the PHY’s auto-negotiation.
0: PHY is unable to perform auto-negotiation
1: PHY is able to perform auto-negotiation
RO 1b
2Link Status
This bit indicates the status of the link.
0: Link is down
1: Link is up
RO/LL 0b
1Jabber Detect
This bit indicates the status of the jabber condition.
0: No jabber condition detected
1: Jabber condition detected
RO/LH 0b
0Extended Capability
This bit indicates whether extended register capability is supported.
0: Basic register set capabilities only
1: Extended register set capabilities
RO 1b
BITS DESCRIPTION TYPE DEFAULT
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13.3.2.3 Port x PHY Identification MSB Register (PHY_ID_MSB_x)
This read/write register contains the MSB of the Organizationally Unique Identifier (OUI) for the Port x
PHY. The LSB of the PHY OUI is contained in the Port x PHY Identification LSB Register
(PHY_ID_LSB_x).
Index (decimal): 2 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15:0 PHY ID
This field is assigned to the 3rd through 18th bits of the OUI, respectively
(OUI = 00800Fh).
R/W 0007h
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13.3.2.4 Port x PHY Identification LSB Register (PHY_ID_LSB_x)
This read/write register contains the LSB of the Organizationally Unique Identifier (OUI) for the Port x
PHY. The MSB of the PHY OUI is contained in the Port x PHY Identification MSB Register
(PHY_ID_MSB_x).
Index (decimal): 3 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15:10 PHY ID
This field is assigned to the 19th through 24th bits of the PHY OUI,
respectively. (OUI = 00800Fh).
R/W 110000b
9:4 Model Number
This field contains the 6-bit manufacturer’s model number of the PHY.
R/W 001101b
3:0 Revision Number
This field contain the 4-bit manufacturer’s revision number of the PHY.
R/W 0001b
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13.3.2.5 Port x PHY Auto-Negotiation Advertisement Register (PHY_AN_ADV_x)
This read/write register contains the advertised ability of the Port x PHY and is used in the Auto-
Negotiation process with the link partner.
Note: This register is re-written by the EEPROM Loader following the release of reset or a RELOAD
command. Refer to Section 8.4, "EEPROM Loader," on page 121 for additional information.
Index (decimal): 4 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15:14 RESERVED RO -
13 Remote Fault
This bit determines if remote fault indication will be advertised to the link
partner.
0: Remote fault indication not advertised
1: Remote fault indication advertised
R/W 0b
12 RESERVED
Note: This bit should be written as 0.
R/W 0b
11 Asymmetric Pause
This bit determines the advertised asymmetric pause capability.
0: No Asymmetric PAUSE toward link partner advertised
1: Asymmetric PAUSE toward link partner advertised
R/W Note 13.67
10 Symmetric Pause
This bit determines the advertised symmetric pause capability.
0: No Symmetric PAUSE toward link partner advertised
1: Symmetric PAUSE toward link partner advertised
R/W Note 13.67
9RESERVED RO -
8100BASE-X Full Duplex
This bit determines the advertised 100BASE-X full duplex capability.
0: 100BASE-X full duplex ability not advertised
1: 100BASE-X full duplex ability advertised
R/W Note 13.68
7100BASE-X Half Duplex
This bit determines the advertised 100BASE-X half duplex capability.
0: 100BASE-X half duplex ability not advertised
1: 100BASE-X half duplex ability advertised
R/W 1b
610BASE-T Full Duplex
This bit determines the advertised 10BASE-T full duplex capability.
0: 10BASE-T full duplex ability not advertised
1: 10BASE-T full duplex ability advertised
R/W Note 13.69
Table 13.9
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Note 13.67 The Asymmetric Pause and Symmetric Pause bits are loaded into the PHY registers by
the EEPROM Loader. For Port 1 operating in an external mode (MII PHY, RMII PHY, or
MII MAC mode), the default value of both these bits is 0 and is independent of any strap.
For Port 1 operating in Internal PHY mode and for all operating modes of Port 2, the
default values of the Asymmetric Pause and Symmetric Pause bits are determined by the
Manual Flow Control Enable Strap (manual_FC_strap_1 for Port 1 PHY,
manual_FC_strap_2 for Port 2 PHY). When the Manual Flow Control Enable Strap is 0,
the Symmetric Pause bit defaults to 1 and the Asymmetric Pause bit defaults to the setting
of the Full Duplex Flow Control Enable Strap (FD_FC_strap_1 for Port 1 PHY,
FD_FC_strap_2 for Port 2 PHY). When the Manual Flow Control Enable Strap is 1, both
bits default to 0. Configuration strap values are latched upon the de-assertion of a chip-
level reset as described in Section 4.2.4, "Configuration Straps," on page 52. Refer to
Section 4.2.4, "Configuration Straps," on page 52 for configuration strap definitions.
Note 13.68 For Port 1 operating in an external mode (MII PHY, RMII PHY, or MII MAC mode), the
default value of this bit is 0. For Port 1 operating in Internal PHY mode and for all operating
modes of Port 2, the default value is 1.
Note 13.69 For Port 1 operating in an external mode (MII PHY, RMII PHY, or MII MAC mode), the
default value of this bit is 1 and is independent of any strap. For Port 1 operating in Internal
PHY mode and for all operating modes of Port 2, the default value of this bit is determined
by the logical OR of the Auto-Negotiation Enable strap (autoneg_strap_1 for Port 1 PHY,
autoneg_strap_2 for Port 2 PHY) with the logical AND of the negated Speed Select strap
(speed_strap_1 for Port 1 PHY, speed_strap_2 for Port 2 PHY) and the Duplex Select
Strap (duplex_strap_1 for Port 1 PHY, duplex_strap_2 for Port 2 PHY). Ta b l e 1 3 .9 defines
the default behavior of this bit. Configuration strap values are latched upon the de-
assertion of a chip-level reset as described in Section 4.2.4, "Configuration Straps," on
page 52. Refer to Section 4.2.4, "Configuration Straps," on page 52 for configuration strap
definitions.
510BASE-T Half Duplex
This bit determines the advertised 10BASE-T half duplex capability.
0: 10BASE-T half duplex ability not advertised
1: 10BASE-T half duplex ability advertised
R/W Note 13.70
Table 13.10
4:0 Selector Field
This field identifies the type of message being sent by Auto-Negotiation.
00001: IEEE 802.3
R/W 00001b
Table 13.9 10BASE-T Full Duplex Advertisement Default Value
autoneg_strap_x speed_strap_x duplex_strap_x Default 10BASE-T Full Duplex Value
000 0
001 1
010 0
011 0
100 1
101 1
110 1
111 1
BITS DESCRIPTION TYPE DEFAULT
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Note 13.70 For Port 1 operating in an external mode (MII PHY, RMII PHY, or MII MAC mode), the
default value of this bit is 1 and is independent of any strap. For Port 1 operating in Internal
PHY mode and for all operating modes of Port 2, the default value of this bit is determined
by the logical OR of the Auto-Negotiation Enable strap (autoneg_strap_1 for Port 1 PHY,
autoneg_strap_2 for Port 2 PHY) and the negated Speed Select strap (speed_strap_1 for
Port 1 PHY, speed_strap_2 for Port 2 PHY). Table 13.10 defines the default behavior of
this bit. Configuration strap values are latched upon the de-assertion of a chip-level reset
as described in Section 4.2.4, "Configuration Straps," on page 52. Refer to Section 4.2.4,
"Configuration Straps," on page 52 for configuration strap definitions.
Table 13.10 10BASE-T Half Duplex Advertisement Bit Default Value
autoneg_strap_x speed_strap_x Default 10BASE-T Half Duplex Value
00 1
01 0
10 1
11 1
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13.3.2.6 Port x PHY Auto-Negotiation Link Partner Base Page Ability Register
(PHY_AN_LP_BASE_ABILITY_x)
This read-only register contains the advertised ability of the link partner’s PHY and is used in the Auto-
Negotiation process between the link partner and the Port x PHY.
Index (decimal): 5 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15 Next Page
This bit indicates the link partner PHY page capability.
0: Link partner PHY does not advertise next page capability
1: Link partner PHY advertises next page capability
RO 0b
14 Acknowledge
This bit indicates whether the link code word has been received from the
partner.
0: Link code word not yet received from partner
1: Link code word received from partner
RO 0b
13 Remote Fault
This bit indicates whether a remote fault has been detected.
0: No remote fault
1: Remote fault detected
RO 0b
12 RESERVED RO -
11 Asymmetric Pause
This bit indicates the link partner PHY asymmetric pause capability.
0: No Asymmetric PAUSE toward link partner
1: Asymmetric PAUSE toward link partner
RO 0b
10 Pause
This bit indicates the link partner PHY symmetric pause capability.
0: No Symmetric PAUSE toward link partner
1: Symmetric PAUSE toward link partner
RO 0b
9100BASE-T4
This bit indicates the link partner PHY 100BASE-T4 capability.
0: 100BASE-T4 ability not supported
1: 100BASE-T4 ability supported
RO 0b
8100BASE-X Full Duplex
This bit indicates the link partner PHY 100BASE-X full duplex capability.
0: 100BASE-X full duplex ability not supported
1: 100BASE-X full duplex ability supported
RO 0b
7100BASE-X Half Duplex
This bit indicates the link partner PHY 100BASE-X half duplex capability.
0: 100BASE-X half duplex ability not supported
1: 100BASE-X half duplex ability supported
RO 0b
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Note 13.71 The Port 1 & 2 PHY’s support only IEEE 802.3.
610BASE-T Full Duplex
This bit indicates the link partner PHY 10BASE-T full duplex capability.
0: 10BASE-T full duplex ability not supported
1: 10BASE-T full duplex ability supported
RO 0b
510BASE-T Half Duplex
This bit indicates the link partner PHY 10BASE-T half duplex capability.
0: 10BASE-T half duplex ability not supported
1: 10BASE-T half duplex ability supported
RO 0b
4:0 Selector Field
This field identifies the type of message being sent by Auto-Negotiation.
00001: IEEE 802.3
RO 00001b
Note 13.71
BITS DESCRIPTION TYPE DEFAULT
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13.3.2.7 Port x PHY Auto-Negotiation Expansion Register (PHY_AN_EXP_x)
This read/write register is used in the Auto-Negotiation process between the link partner and the Port
x PHY.
Index (decimal): 6 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15:5 RESERVED RO -
4Parallel Detection Fault
This bit indicates whether a Parallel Detection Fault has been detected.
0: A fault hasn’t been detected via the Parallel Detection function
1: A fault has been detected via the Parallel Detection function
RO/LH 0b
3Link Partner Next Page Able
This bit indicates whether the link partner has next page ability.
0: Link partner does not contain next page capability
1: Link partner contains next page capability
RO 0b
2Local Device Next Page Able
This bit indicates whether the local device has next page ability.
0: Local device does not contain next page capability
1: Local device contains next page capability
RO 0b
1Page Received
This bit indicates the reception of a new page.
0: A new page has not been received
1: A new page has been received
RO/LH 0b
0Link Partner Auto-Negotiation Able
This bit indicates the Auto-negotiation ability of the link partner.
0: Link partner is not Auto-Negotiation able
1: Link partner is Auto-Negotiation able
RO 0b
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13.3.2.8 Port x PHY Mode Control/Status Register (PHY_MODE_CONTROL_STATUS_x)
This read/write register is used to control and monitor various Port x PHY configuration options.
Index (decimal): 17 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15:14 RESERVED RO -
13 Energy Detect Power-Down (EDPWRDOWN)
This bit controls the Energy Detect Power-Down mode.
0: Energy Detect Power-Down is disabled
1: Energy Detect Power-Down is enabled
R/W 0b
12:2 RESERVED RO -
1Energy On (ENERGYON)
This bit indicates whether energy is detected on the line. It is cleared if no
valid energy is detected within 256ms. This bit is unaffected by a software
reset and is reset to 1 by a hardware reset.
0: No valid energy detected on the line
1: Energy detected on the line
RO 1b
0RESERVED R/W 0b
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13.3.2.9 Port x PHY Special Modes Register (PHY_SPECIAL_MODES_x)
This read/write register is used to control the special modes of the Port x PHY.
Note: This register is re-written by the EEPROM Loader following the release of reset or a RELOAD
command. Refer to Section 8.4, "EEPROM Loader," on page 121 for more information.
Note 13.72 Register bits designated as NASR are reset when the Port x PHY Reset is generated via
the Reset Control Register (RESET_CTL). The NASR designation is only applicable when
the Reset (PHY_RST) bit of the Port x PHY Basic Control Register
(PHY_BASIC_CONTROL_x) is set.
Note 13.73 For Port 1 operating in an external mode (MII PHY, RMII PHY, or MII MAC mode), the
default value of this field is 110b and is independent of any strap. For Port 1 operating in
Internal PHY mode and for all operating modes of Port 2, the default value of this field is
determined by a combination of the configuration straps autoneg_strap_x, speed_strap_x,
and duplex_strap_x. If the autoneg_strap_x is 1, then the default MODE[2:0] value is 111b.
Else, the default value of this field is determined by the remaining straps. MODE[2]=0,
MODE[1]=(speed_strap_1 for Port 1 PHY, speed_strap_2 for Port 2 PHY), and
MODE[0]=(duplex_strap_1 for Port 1 PHY, duplex_strap_2 for Port 2 PHY). Configuration
strap values are latched upon the de-assertion of a chip-level reset as described in Section
4.2.4, "Configuration Straps," on page 52. Refer to Section 4.2.4, "Configuration Straps,"
on page 52 for strap definitions.
Note 13.74 The default value of this field is determined by the phy_addr_sel_strap configuration strap.
Refer to Section 7.1.1, "PHY Addressing," on page 96 for additional information.
Index (decimal): 18 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15:8 RESERVED RO -
7:5 PHY Mode (MODE[2:0])
This field reflects the default PHY mode of operation. Refer to Table 13.11
for a definition of each mode.
R/W
NASR
Note 13.72
Note 13.73
4:0 PHY Address (PHYADD)
The PHY Address field determines the MMI address to which the PHY will
respond and is also used for initialization of the cipher (scrambler) key. Each
PHY must have a unique address. Refer to Section 7.1.1, "PHY
Addressing," on page 96 for additional information.
Note: No check is performed to ensure this address is unique from the
other PHY addresses (Port 1 PHY, Port 2 PHY, and Virtual PHY).
R/W
NASR
Note 13.72
Note 13.74
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Table 13.11 MODE[2:0] Definitions
MODE[2:0] MODE DEFINITIONS
000 10BASE-T Half Duplex. Auto-negotiation disabled.
001 10BASE-T Full Duplex. Auto-negotiation disabled.
010 100BASE-TX Half Duplex. Auto-negotiation disabled. CRS is active during Transmit & Receive.
011 100BASE-TX Full Duplex. Auto-negotiation disabled. CRS is active during Receive.
100 RESERVED
101 RESERVED
110 Power Down mode.
111 All capable. Auto-negotiation enabled.
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13.3.2.10 Port x PHY Special Control/Status Indication Register (PHY_SPECIAL_CONTROL_STAT_IND_x)
This read/write register is used to control various options of the Port x PHY.
Index (decimal): 27 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15 Auto-MDIX Control (AMDIXCTRL)
This bit is responsible for determining the source of Auto-MDIX control for
Port x. When set, the Manual MDIX and Auto MDIX straps
(manual_mdix_strap_1/auto_mdix_strap_1 for Port 1 PHY,
manual_mdix_strap_2/auto_mdix_strap_2 for Port 2 PHY) are overridden,
and Auto-MDIX functions are controlled using the AMDIXEN and
AMDIXSTATE bits of this register. When cleared, Auto-MDIX functionality is
controlled by the Manual MDIX and Auto MDIX straps by default. Refer to
Section 4.2.4, "Configuration Straps," on page 52 for configuration strap
definitions.
0: Port x Auto-MDIX determined by strap inputs (Table 13.13)
1: Port x Auto-MDIX determined by bits AMDIXEN and AMDIXSTATE
bits
Note: The values of auto_mdix_strap_1 and auto_mdix_strap_2 are
indicated in the AMDIX_EN Strap State Port 1 and the AMDIX_EN
Strap State Port 2 bits of the Hardware Configuration Register
(HW_CFG).
R/W
NASR
Note 13.75
0b
14 Auto-MDIX Enable (AMDIXEN)
When the AMDIXCTRL bit of this register is set, this bit is used in
conjunction with the AMDIXSTATE bit to control the Port x Auto-MDIX
functionality as shown in Table 13.12.
R/W
NASR
Note 13.75
0b
13 Auto-MDIX State (AMDIXSTATE)
When the AMDIXCTRL bit of this register is set, this bit is used in
conjunction with the AMDIXEN bit to control the Port x Auto-MDIX
functionality as shown in Table 13.12.
R/W
NASR
Note 13.75
0b
12 RESERVED RO -
11 SQE Test Disable (SQEOFF)
This bit controls the disabling of the SQE test (Heartbeat). SQE test is
enabled by default.
0: SQE test enabled
1: SQE test disabled
R/W
NASR
Note 13.75
0b
10 Receive PLL Lock Control (VCOOFF_LP)
This bit controls the locking of the receive PLL. Setting this bit to 1 forces
the receive PLL 10M to lock on the reference clock at all times. When in this
mode, 10M data packets cannot be received.
0: Receive PLL 10M can lock on reference or line as needed (normal
operation)
1: Receive PLL 10M locked onto reference clock at all times
R/W
NASR
Note 13.75
0b
9:5 RESERVED RO -
410Base-T Polarity State (XPOL)
This bit shows the polarity state of the 10Base-T.
0: Normal Polarity
1: Reversed Polarity
RO 0b
3:0 RESERVED RO -
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Note 13.75 Register bits designated as NASR are reset when the Port x PHY Reset is generated via
the Reset Control Register (RESET_CTL). The NASR designation is only applicable when
the Reset (PHY_RST) bit of the Port x PHY Basic Control Register
(PHY_BASIC_CONTROL_x) is set.
Table 13.12 Auto-MDIX Enable and Auto-MDIX State Bit Functionality
Auto-MDIX Enable Auto-MDIX State MODE
0 0 Manual mode, no crossover
0 1 Manual mode, crossover
10 Auto-MDIX mode
1 1 RESERVED (do not use this state)
Table 13.13 MDIX Strap Functionality
auto_mdix_strap_x manual_mdix_strap_x MODE
0 0 Manual mode, no crossover
0 1 Manual mode, crossover
1x Auto-MDIX mode
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13.3.2.11 Port x PHY Interrupt Source Flags Register (PHY_INTERRUPT_SOURCE_x)
This read-only register is used to determine to source of various Port x PHY interrupts. All interrupt
source bits in this register are read-only and latch high upon detection of the corresponding interrupt
(if enabled). A read of this register clears the interrupts. These interrupts are enabled or masked via
the Port x PHY Interrupt Mask Register (PHY_INTERRUPT_MASK_x).
Index (decimal): 29 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15:8 RESERVED RO -
7INT7
This interrupt source bit indicates when the Energy On (ENERGYON) bit of
the Port x PHY Mode Control/Status Register
(PHY_MODE_CONTROL_STATUS_x) has been set.
0: Not source of interrupt
1: ENERGYON generated
RO/LH 0b
6INT6
This interrupt source bit indicates Auto-Negotiation is complete.
0: Not source of interrupt
1: Auto-Negotiation complete
RO/LH 0b
5INT5
This interrupt source bit indicates a remote fault has been detected.
0: Not source of interrupt
1: Remote fault detected
RO/LH 0b
4INT4
This interrupt source bit indicates a Link Down (link status negated).
0: Not source of interrupt
1: Link Down (link status negated)
RO/LH 0b
3INT3
This interrupt source bit indicates an Auto-Negotiation LP acknowledge.
0: Not source of interrupt
1: Auto-Negotiation LP acknowledge
RO/LH 0b
2INT2
This interrupt source bit indicates a Parallel Detection fault.
0: Not source of interrupt
1: Parallel Detection fault
RO/LH 0b
1INT1
This interrupt source bit indicates an Auto-Negotiation page received.
0: Not source of interrupt
1: Auto-Negotiation page received
RO/LH 0b
0RESERVED RO -
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13.3.2.12 Port x PHY Interrupt Mask Register (PHY_INTERRUPT_MASK_x)
This read/write register is used to enable or mask the various Port x PHY interrupts and is used in
conjunction with the Port x PHY Interrupt Source Flags Register (PHY_INTERRUPT_SOURCE_x).
Index (decimal): 30 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15:8 RESERVED RO -
7INT7_MASK
This interrupt mask bit enables/masks the ENERGYON interrupt.
0: Interrupt source is masked
1: Interrupt source is enabled
R/W 0b
6INT6_MASK
This interrupt mask bit enables/masks the Auto-Negotiation interrupt.
0: Interrupt source is masked
1: Interrupt source is enabled
R/W 0b
5INT5_MASK
This interrupt mask bit enables/masks the remote fault interrupt.
0: Interrupt source is masked
1: Interrupt source is enabled
R/W 0b
4INT4_MASK
This interrupt mask bit enables/masks the Link Down (link status negated)
interrupt.
0: Interrupt source is masked
1: Interrupt source is enabled
R/W 0b
3INT3_MASK
This interrupt mask bit enables/masks the Auto-Negotiation LP acknowledge
interrupt.
0: Interrupt source is masked
1: Interrupt source is enabled
R/W 0b
2INT2_MASK
This interrupt mask bit enables/masks the Parallel Detection fault interrupt.
0: Interrupt source is masked
1: Interrupt source is enabled
R/W 0b
1INT1_MASK
This interrupt mask bit enables/masks the Auto-Negotiation page received
interrupt.
0: Interrupt source is masked
1: Interrupt source is enabled
R/W 0b
0RESERVED RO -
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13.3.2.13 Port x PHY Special Control/Status Register (PHY_SPECIAL_CONTROL_STATUS_x)
This read/write register is used to control and monitor various options of the Port x PHY.
Note 13.76 Default value is 010b if any external MII mode is selected, else 000b.
Index (decimal): 31 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15:13 RESERVED RO -
12 Autodone
This bit indicates the status of the Auto-Negotiation on the Port x PHY.
0: Auto-Negotiation is not completed, is disabled, or is not active
1: Auto-Negotiation is completed
RO 0b
11:5 RESERVED - Write as 0000010b, ignore on read R/W 0000010b
4:2 Speed Indication
This field indicates the current Port x speed configuration.
RO Note 13.76
1:0 RESERVED R/W 0b
STATE DESCRIPTION
000 RESERVED
001 10BASE-T Half-duplex
010 100BASE-TX Half-duplex
011 RESERVED
100 RESERVED
101 10BASE-T Full-duplex
110 100BASE-TX Full-duplex
111 RESERVED
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13.4 Switch Fabric Control and Status Registers
This section details the various switch control and status registers that reside within the Switch Fabric.
The switch control and status registers allow configuration of each individual switch port, the Switch
Engine, and Buffer Manager. Switch Fabric related interrupts and resets are also controlled and
monitored via the switch CSRs.
The switch CSRs are not memory mapped. All switch CSRs are accessed indirectly via the Switch
Fabric CSR Interface Command Register (SWITCH_CSR_CMD), Switch Fabric CSR Interface Data
Register (SWITCH_CSR_DATA), and Switch Fabric CSR Interface Direct Data Registers
(SWITCH_CSR_DIRECT_DATA) in the system CSR memory mapped address space. All accesses to
the switch CSRs must be performed through these registers. Refer to Section 13.2.4, "Switch Fabric"
for additional information.
Note: The flow control settings of the switch ports are configured via the Switch Fabric registers: Port
1 Manual Flow Control Register (MANUAL_FC_1), Port 2 Manual Flow Control Register
(MANUAL_FC_2), and Port 0 Manual Flow Control Register (MANUAL_FC_0) located in the
system CSR address space.
Table 13.14 lists the Switch CSRs and their corresponding addresses in order. The Switch Fabric
registers can be categorized into the following sub-sections:
Section 13.4.1, "General Switch CSRs," on page 239
Section 13.4.2, "Switch Port 0, Port 1, and Port 2 CSRs," on page 243
Section 13.4.3, "Switch Engine CSRs," on page 287
Section 13.4.4, "Buffer Manager CSRs," on page 334
Table 13.14 Indirectly Accessible Switch Control and Status Registers
REGISTER # SYMBOL REGISTER NAME
General Switch CSRs
0000h SW_DEV_ID Switch Device ID Register, Section 13.4.1.1
0001h SW_RESET Switch Reset Register, Section 13.4.1.2
0002h-0003h RESERVED Reserved for Future Use
0004h SW_IMR Switch Global Interrupt Mask Register, Section 13.4.1.3
0005h SW_IPR Switch Global Interrupt Pending Register, Section 13.4.1.4
0006h-03FFh RESERVED Reserved for Future Use
Switch Port 0 CSRs
0400h MAC_VER_ID_0 Port 0 MAC Version ID Register, Section 13.4.2.1
0401h MAC_RX_CFG_0 Port 0 MAC Receive Configuration Register, Section 13.4.2.2
0402h-040Fh RESERVED Reserved for Future Use
0410h MAC_RX_UNDSZE_CNT_0 Port 0 MAC Receive Undersize Count Register,
Section 13.4.2.3
0411h MAC_RX_64_CNT_0 Port 0 MAC Receive 64 Byte Count Register, Section 13.4.2.4
0412h MAC_RX_65_TO_127_CNT_0 Port 0 MAC Receive 65 to 127 Byte Count Register,
Section 13.4.2.5
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 229 Revision 1.5 (07-08-11)
DATASHEET
0413h MAC_RX_128_TO_255_CNT_0 Port 0 MAC Receive 128 to 255 Byte Count Register,
Section 13.4.2.6
0414h MAC_RX_256_TO_511_CNT_0 Port 0 MAC Receive 256 to 511 Byte Count Register,
Section 13.4.2.7
0415h MAC_RX_512_TO_1023_CNT_0 Port 0 MAC Receive 512 to 1023 Byte Count Register,
Section 13.4.2.8
0416h MAC_RX_1024_TO_MAX_CNT_0 Port 0 MAC Receive 1024 to Max Byte Count Register,
Section 13.4.2.9
0417h MAC_RX_OVRSZE_CNT_0 Port 0 MAC Receive Oversize Count Register,
Section 13.4.2.10
0418h MAC_RX_PKTOK_CNT_0 Port 0 MAC Receive OK Count Register, Section 13.4.2.11
0419h MAC_RX_CRCERR_CNT_0 Port 0 MAC Receive CRC Error Count Register,
Section 13.4.2.12
041Ah MAC_RX_MULCST_CNT_0 Port 0 MAC Receive Multicast Count Register,
Section 13.4.2.13
041Bh MAC_RX_BRDCST_CNT_0 Port 0 MAC Receive Broadcast Count Register,
Section 13.4.2.14
041Ch MAC_RX_PAUSE_CNT_0 Port 0 MAC Receive Pause Frame Count Register,
Section 13.4.2.15
041Dh MAC_RX_FRAG_CNT_0 Port 0 MAC Receive Fragment Error Count Register,
Section 13.4.2.16
041Eh MAC_RX_JABB_CNT_0 Port 0 MAC Receive Jabber Error Count Register,
Section 13.4.2.17
041Fh MAC_RX_ALIGN_CNT_0 Port 0 MAC Receive Alignment Error Count Register,
Section 13.4.2.18
0420h MAC_RX_PKTLEN_CNT_0 Port 0 MAC Receive Packet Length Count Register,
Section 13.4.2.19
0421h MAC_RX_GOODPKTLEN_CNT_0 Port 0 MAC Receive Good Packet Length Count Register,
Section 13.4.2.20
0422h MAC_RX_SYMBL_CNT_0 Port 0 MAC Receive Symbol Error Count Register,
Section 13.4.2.21
0423h MAC_RX_CTLFRM_CNT_0 Port 0 MAC Receive Control Frame Count Register,
Section 13.4.2.22
0424h-043Fh RESERVED Reserved for Future Use
0440h MAC_TX_CFG_0 Port 0 MAC Transmit Configuration Register, Section 13.4.2.23
0441h MAC_TX_FC_SETTINGS_0 Port 0 MAC Transmit Flow Control Settings Register,
Section 13.4.2.24
0442h-0450h RESERVED Reserved for Future Use
0451h MAC_TX_DEFER_CNT_0I Port 0 MAC Transmit Deferred Count Register,
Section 13.4.2.25
0452h MAC_TX_PAUSE_CNT_0 Port 0 MAC Transmit Pause Count Register, Section 13.4.2.26
Table 13.14 Indirectly Accessible Switch Control and Status Registers (continued)
REGISTER # SYMBOL REGISTER NAME
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 230 SMSC LAN9303M/LAN9303Mi
DATASHEET
0453h MAC_TX_PKTOK_CNT_0 Port 0 MAC Transmit OK Count Register, Section 13.4.2.27
0454h MAC_TX_64_CNT_0 Port 0 MAC Transmit 64 Byte Count Register, Section 13.4.2.28
0455h MAC_TX_65_TO_127_CNT_0 Port 0 MAC Transmit 65 to 127 Byte Count Register,
Section 13.4.2.29
0456h MAC_TX_128_TO_255_CNT_0 Port 0 MAC Transmit 128 to 255 Byte Count Register,
Section 13.4.2.30
0457h MAC_TX_256_TO_511_CNT_0 Port 0 MAC Transmit 256 to 511 Byte Count Register,
Section 13.4.2.31
0458h MAC_TX_512_TO_1023_CNT_0 Port 0 MAC Transmit 512 to 1023 Byte Count Register,
Section 13.4.2.32
0459h MAC_TX_1024_TO_MAX_CNT_0 Port 0 MAC Transmit 1024 to Max Byte Count Register,
Section 13.4.2.33
045Ah MAC_TX_UNDSZE_CNT_0 Port 0 MAC Transmit Undersize Count Register,
Section 13.4.2.34
045Bh RESERVED Reserved for Future Use
045Ch MAC_TX_PKTLEN_CNT_0 Port 0 MAC Transmit Packet Length Count Register,
Section 13.4.2.35
045Dh MAC_TX_BRDCST_CNT_0 Port 0 MAC Transmit Broadcast Count Register,
Section 13.4.2.36
045Eh MAC_TX_MULCST_CNT_0 Port 0 MAC Transmit Multicast Count Register,
Section 13.4.2.37
045Fh MAC_TX_LATECOL_0 Port 0 MAC Transmit Late Collision Count Register,
Section 13.4.2.38
0460h MAC_TX_EXCOL_CNT_0 Port 0 MAC Transmit Excessive Collision Count Register,
Section 13.4.2.39
0461h MAC_TX_SNGLECOL_CNT_0 Port 0 MAC Transmit Single Collision Count Register,
Section 13.4.2.40
0462h MAC_TX_MULTICOL_CNT_0 Port 0 MAC Transmit Multiple Collision Count Register,
Section 13.4.2.41
0463h MAC_TX_TOTALCOL_CNT_0 Port 0 MAC Transmit Total Collision Count Register,
Section 13.4.2.42
0464-047Fh RESERVED Reserved for Future Use
0480h MAC_IMR_0 Port 0 MAC Interrupt Mask Register, Section 13.4.2.43
0481h MAC_IPR_0 Port 0 MAC Interrupt Pending Register, Section 13.4.2.44
0482h-07FFh RESERVED Reserved for Future Use
Switch Port 1 CSRs
0800h MAC_VER_ID_1 Port 1 MAC Version ID Register, Section 13.4.2.1
0801h MAC_RX_CFG_1 Port 1 MAC Receive Configuration Register, Section 13.4.2.2
0802h-080Fh RESERVED Reserved for Future Use
Table 13.14 Indirectly Accessible Switch Control and Status Registers (continued)
REGISTER # SYMBOL REGISTER NAME
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 231 Revision 1.5 (07-08-11)
DATASHEET
0810h MAC_RX_UNDSZE_CNT_1 Port 1 MAC Receive Undersize Count Register,
Section 13.4.2.3
0811h MAC_RX_64_CNT_1 Port 1 MAC Receive 64 Byte Count Register, Section 13.4.2.4
0812h MAC_RX_65_TO_127_CNT_1 Port 1 MAC Receive 65 to 127 Byte Count Register,
Section 13.4.2.5
0813h MAC_RX_128_TO_255_CNT_1 Port 1 MAC Receive 128 to 255 Byte Count Register,
Section 13.4.2.6
0814h MAC_RX_256_TO_511_CNT_1 Port 1 MAC Receive 256 to 511 Byte Count Register,
Section 13.4.2.7
0815h MAC_RX_512_TO_1023_CNT_1 Port 1 MAC Receive 512 to 1023 Byte Count Register,
Section 13.4.2.8
0816h MAC_RX_1024_TO_MAX_CNT_1 Port 1 MAC Receive 1024 to Max Byte Count Register,
Section 13.4.2.9
0817h MAC_RX_OVRSZE_CNT_1 Port 1 MAC Receive Oversize Count Register,
Section 13.4.2.10
0818h MAC_RX_PKTOK_CNT_1 Port 1 MAC Receive OK Count Register, Section 13.4.2.11
0819h MAC_RX_CRCERR_CNT_1 Port 1 MAC Receive CRC Error Count Register,
Section 13.4.2.12
081Ah MAC_RX_MULCST_CNT_1 Port 1 MAC Receive Multicast Count Register,
Section 13.4.2.13
081Bh MAC_RX_BRDCST_CNT_1 Port 1 MAC Receive Broadcast Count Register,
Section 13.4.2.14
081Ch MAC_RX_PAUSE_CNT_1 Port 1 MAC Receive Pause Frame Count Register,
Section 13.4.2.15
081Dh MAC_RX_FRAG_CNT_1 Port 1 MAC Receive Fragment Error Count Register,
Section 13.4.2.16
081Eh MAC_RX_JABB_CNT_1 Port 1 MAC Receive Jabber Error Count Register,
Section 13.4.2.17
081Fh MAC_RX_ALIGN_CNT_1 Port 1 MAC Receive Alignment Error Count Register,
Section 13.4.2.18
0820h MAC_RX_PKTLEN_CNT_1 Port 1 MAC Receive Packet Length Count Register,
Section 13.4.2.19
0821h MAC_RX_GOODPKTLEN_CNT_1 Port 1 MAC Receive Good Packet Length Count Register,
Section 13.4.2.20
0822h MAC_RX_SYMBL_CNT_1 Port 1 MAC Receive Symbol Error Count Register,
Section 13.4.2.21
0823h MAC_RX_CTLFRM_CNT_1 Port 1 MAC Receive Control Frame Count Register,
Section 13.4.2.22
0824h-083Fh RESERVED Reserved for Future Use
0840h MAC_TX_CFG_1 Port 1 MAC Transmit Configuration Register, Section 13.4.2.23
0841h MAC_TX_FC_SETTINGS_1 Port 1 MAC Transmit Flow Control Settings Register,
Section 13.4.2.24
Table 13.14 Indirectly Accessible Switch Control and Status Registers (continued)
REGISTER # SYMBOL REGISTER NAME
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 232 SMSC LAN9303M/LAN9303Mi
DATASHEET
0842h-0850h RESERVED Reserved for Future Use
0851h MAC_TX_DEFER_CNT_1 Port 1 MAC Transmit Deferred Count Register,
Section 13.4.2.25
0852h MAC_TX_PAUSE_CNT_1 Port 1 MAC Transmit Pause Count Register, Section 13.4.2.26
0853h MAC_TX_PKTOK_CNT_1 Port 1 MAC Transmit OK Count Register, Section 13.4.2.27
0854h MAC_RX_64_CNT_1 Port 1 MAC Transmit 64 Byte Count Register, Section 13.4.2.28
0855h MAC_TX_65_TO_127_CNT_1 Port 1 MAC Transmit 65 to 127 Byte Count Register,
Section 13.4.2.29
0856h MAC_TX_128_TO_255_CNT_1 Port 1 MAC Transmit 128 to 255 Byte Count Register,
Section 13.4.2.30
0857h MAC_TX_256_TO_511_CNT_1 Port 1 MAC Transmit 256 to 511 Byte Count Register,
Section 13.4.2.31
0858h MAC_TX_512_TO_1023_CNT_1 Port 1 MAC Transmit 512 to 1023 Byte Count Register,
Section 13.4.2.32
0859h MAC_TX_1024_TO_MAX_CNT_1 Port 1 MAC Transmit 1024 to Max Byte Count Register,
Section 13.4.2.33
085Ah MAC_TX_UNDSZE_CNT_1 Port 1 MAC Transmit Undersize Count Register,
Section 13.4.2.34
085Bh RESERVED Reserved for Future Use
085Ch MAC_TX_PKTLEN_CNT_1 Port 1 MAC Transmit Packet Length Count Register,
Section 13.4.2.35
085Dh MAC_TX_BRDCST_CNT_1 Port 1 MAC Transmit Broadcast Count Register,
Section 13.4.2.36
085Eh MAC_TX_MULCST_CNT_1 Port 1 MAC Transmit Multicast Count Register,
Section 13.4.2.37
085Fh MAC_TX_LATECOL_1 Port 1 MAC Transmit Late Collision Count Register,
Section 13.4.2.38
0860h MAC_TX_EXCOL_CNT_1 Port 1 MAC Transmit Excessive Collision Count Register,
Section 13.4.2.39
0861h MAC_TX_SNGLECOL_CNT_1 Port 1 MAC Transmit Single Collision Count Register,
Section 13.4.2.40
0862h MAC_TX_MULTICOL_CNT_1 Port 1 MAC Transmit Multiple Collision Count Register,
Section 13.4.2.41
0863h MAC_TX_TOTALCOL_CNT_1 Port 1 MAC Transmit Total Collision Count Register,
Section 13.4.2.42
0864-087Fh RESERVED Reserved for Future Use
0880h MAC_IMR_1 Port 1 MAC Interrupt Mask Register, Section 13.4.2.43
0881h MAC_IPR_1 Port 1 MAC Interrupt Pending Register, Section 13.4.2.44
0882h-0BFFh RESERVED Reserved for Future Use
Switch Port 2 CSRs
Table 13.14 Indirectly Accessible Switch Control and Status Registers (continued)
REGISTER # SYMBOL REGISTER NAME
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 233 Revision 1.5 (07-08-11)
DATASHEET
0C00h MAC_VER_ID_2 Port 2 MAC Version ID Register, Section 13.4.2.1
0C01h MAC_RX_CFG_2 Port 2 MAC Receive Configuration Register, Section 13.4.2.2
0C02h-0C0FhRESERVED Reserved for Future Use
0C10h MAC_RX_UNDSZE_CNT_2 Port 2 MAC Receive Undersize Count Register,
Section 13.4.2.3
0C11h MAC_RX_64_CNT_2 Port 2 MAC Receive 64 Byte Count Register, Section 13.4.2.4
0C12h MAC_RX_65_TO_127_CNT_2 Port 2 MAC Receive 65 to 127 Byte Count Register,
Section 13.4.2.5
0C13h MAC_RX_128_TO_255_CNT_2 Port 2 MAC Receive 128 to 255 Byte Count Register,
Section 13.4.2.6
0C14h MAC_RX_256_TO_511_CNT_2 Port 2 MAC Receive 256 to 511 Byte Count Register,
Section 13.4.2.7
0C15h MAC_RX_512_TO_1023_CNT_2 Port 2 MAC Receive 512 to 1023 Byte Count Register,
Section 13.4.2.8
0C16h MAC_RX_1024_TO_MAX_CNT_2 Port 2 MAC Receive 1024 to Max Byte Count Register,
Section 13.4.2.9
0C17h MAC_RX_OVRSZE_CNT_2 Port 2 MAC Receive Oversize Count Register,
Section 13.4.2.10
0C18h MAC_RX_PKTOK_CNT_2 Port 2 MAC Receive OK Count Register, Section 13.4.2.11
0C19h MAC_RX_CRCERR_CNT_2 Port 2 MAC Receive CRC Error Count Register,
Section 13.4.2.12
0C1Ah MAC_RX_MULCST_CNT_2 Port 2 MAC Receive Multicast Count Register,
Section 13.4.2.13
0C1Bh MAC_RX_BRDCST_CNT_2 Port 2 MAC Receive Broadcast Count Register,
Section 13.4.2.14
0C1Ch MAC_RX_PAUSE_CNT_2 Port 2 MAC Receive Pause Frame Count Register,
Section 13.4.2.15
0C1Dh MAC_RX_FRAG_CNT_2 Port 2 MAC Receive Fragment Error Count Register,
Section 13.4.2.16
0C1Eh MAC_RX_JABB_CNT_2 Port 2 MAC Receive Jabber Error Count Register,
Section 13.4.2.17
0C1Fh MAC_RX_ALIGN_CNT_2 Port 2 MAC Receive Alignment Error Count Register,
Section 13.4.2.18
0C20h MAC_RX_PKTLEN_CNT_2 Port 2 MAC Receive Packet Length Count Register,
Section 13.4.2.19
0C21h MAC_RX_GOODPKTLEN_CNT_2 Port 2 MAC Receive Good Packet Length Count Register,
Section 13.4.2.20
0C22h MAC_RX_SYMBL_CNT_2 Port 2 MAC Receive Symbol Error Count Register,
Section 13.4.2.21
0C23h MAC_RX_CTLFRM_CNT_2 Port 2 MAC Receive Control Frame Count Register,
Section 13.4.2.22
Table 13.14 Indirectly Accessible Switch Control and Status Registers (continued)
REGISTER # SYMBOL REGISTER NAME
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 234 SMSC LAN9303M/LAN9303Mi
DATASHEET
0C24h-0C3FhRESERVED Reserved for Future Use
0C40h MAC_TX_CFG_2 Port 2 MAC Transmit Configuration Register, Section 13.4.2.23
0C41h MAC_TX_FC_SETTINGS_2 Port 2 MAC Transmit Flow Control Settings Register,
Section 13.4.2.24
0C42h-0C50h RESERVED Reserved for Future Use
0C51h MAC_TX_DEFER_CNT_2 Port 2 MAC Transmit Deferred Count Register,
Section 13.4.2.25
0C52h MAC_TX_PAUSE_CNT_2 Port 2 MAC Transmit Pause Count Register, Section 13.4.2.26
0C53h MAC_TX_PKTOK_CNT_2 Port 2 MAC Transmit OK Count Register, Section 13.4.2.27
0C54h MAC_RX_64_CNT_2 Port 2 MAC Transmit 64 Byte Count Register, Section 13.4.2.28
0C55h MAC_TX_65_TO_127_CNT_2 Port 2 MAC Transmit 65 to 127 Byte Count Register,
Section 13.4.2.29
0C56h MAC_TX_128_TO_255_CNT_2 Port 2 MAC Transmit 128 to 255 Byte Count Register,
Section 13.4.2.30
0C57h MAC_TX_256_TO_511_CNT_2 Port 2 MAC Transmit 256 to 511 Byte Count Register,
Section 13.4.2.31
0C58h MAC_TX_512_TO_1023_CNT_2 Port 2 MAC Transmit 512 to 1023 Byte Count Register,
Section 13.4.2.32
0C59h MAC_TX_1024_TO_MAX_CNT_2 Port 2 MAC Transmit 1024 to Max Byte Count Register,
Section 13.4.2.33
0C5Ah MAC_TX_UNDSZE_CNT_2 Port 2 MAC Transmit Undersize Count Register,
Section 13.4.2.34
0C5Bh RESERVED Reserved for Future Use
0C5Ch MAC_TX_PKTLEN_CNT_2 Port 2 MAC Transmit Packet Length Count Register,
Section 13.4.2.35
0C5Dh MAC_TX_BRDCST_CNT_2 Port 2 MAC Transmit Broadcast Count Register,
Section 13.4.2.36
0C5Eh MAC_TX_MULCST_CNT_2 Port 2 MAC Transmit Multicast Count Register,
Section 13.4.2.37
0C5Fh MAC_TX_LATECOL_2 Port 2 MAC Transmit Late Collision Count Register,
Section 13.4.2.38
0C60h MAC_TX_EXCOL_CNT_2 Port 2 MAC Transmit Excessive Collision Count Register,
Section 13.4.2.39
0C61h MAC_TX_SNGLECOL_CNT_2 Port 2 MAC Transmit Single Collision Count Register,
Section 13.4.2.40
0C62h MAC_TX_MULTICOL_CNT_2 Port 2 MAC Transmit Multiple Collision Count Register,
Section 13.4.2.41
0C63h MAC_TX_TOTALCOL_CNT_2 Port 2 MAC Transmit Total Collision Count Register,
Section 13.4.2.42
0C64-0C7Fh RESERVED Reserved for Future Use
Table 13.14 Indirectly Accessible Switch Control and Status Registers (continued)
REGISTER # SYMBOL REGISTER NAME
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 235 Revision 1.5 (07-08-11)
DATASHEET
0C80h MAC_IMR_2 Port 2 MAC Interrupt Mask Register, Section 13.4.2.43
0C81h MAC_IPR_2 Port 2 MAC Interrupt Pending Register, Section 13.4.2.44
0C82h-17FFhRESERVED Reserved for Future Use
Switch Engine CSRs
1800h SWE_ALR_CMD Switch Engine ALR Command Register, Section 13.4.3.1
1801h SWE_ALR_WR_DAT_0 Switch Engine ALR Write Data 0 Register, Section 13.4.3.2
1802h SWE_ALR_WR_DAT_1 Switch Engine ALR Write Data 1 Register, Section 13.4.3.3
1803h-1804h RESERVED Reserved for Future Use
1805h SWE_ALR_RD_DAT_0 Switch Engine ALR Read Data 0 Register, Section 13.4.3.4
1806h SWE_ALR_RD_DAT_1 Switch Engine ALR Read Data 1 Register, Section 13.4.3.5
1807h RESERVED Reserved for Future Use
1808h SWE_ALR_CMD_STS Switch Engine ALR Command Status Register, Section 13.4.3.6
1809h SWE_ALR_CFG Switch Engine ALR Configuration Register, Section 13.4.3.7
180Ah RESERVED Reserved for Future Use
180Bh SWE_VLAN_CMD Switch Engine VLAN Command Register, Section 13.4.3.8
180Ch SWE_VLAN_WR_DATA Switch Engine VLAN Write Data Register, Section 13.4.3.9
180Dh RESERVED Reserved for Future Use
180Eh SWE_VLAN_RD_DATA Switch Engine VLAN Read Data Register, Section 13.4.3.10
180Fh RESERVED Reserved for Future Use
1810h SWE_VLAN_CMD_STS Switch Engine VLAN Command Status Register,
Section 13.4.3.11
1811h SWE_DIFFSERV_TBL_CMD Switch Engine DIFSERV Table Command Register,
Section 13.4.3.12
1812h SWE_DIFFSERV_TBL_WR_DATA Switch Engine DIFFSERV Table Write Data Register,
Section 13.4.3.13
1813h SWE_DIFFSERV_TBL_RD_DATA Switch Engine DIFFSERV Table Read Data Register,
Section 13.4.3.14
1814h SWE_DIFFSERV_TBL_CMD_STS Switch Engine DIFFSERV Table Command Status Register,
Section 13.4.3.15
1815h-183Fh RESERVED Reserved for Future Use
1840h SWE_GLB_INGRESS_CFG Switch Engine Global Ingress Configuration Register,
Section 13.4.3.16
1841h SWE_PORT_INGRESS_CFG Switch Engine Port Ingress Configuration Register,
Section 13.4.3.17
1842h SWE_ADMT_ONLY_VLAN Switch Engine Admit Only VLAN Register, Section 13.4.3.18
Table 13.14 Indirectly Accessible Switch Control and Status Registers (continued)
REGISTER # SYMBOL REGISTER NAME
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 236 SMSC LAN9303M/LAN9303Mi
DATASHEET
1843h SWE_PORT_STATE Switch Engine Port State Register, Section 13.4.3.19
1844h RESERVED Reserved for Future Use
1845h SWE_PRI_TO_QUE Switch Engine Priority to Queue Register, Section 13.4.3.20
1846h SWE_PORT_MIRROR Switch Engine Port Mirroring Register, Section 13.4.3.21
1847h SWE_INGRESS_PORT_TYP Switch Engine Ingress Port Type Register, Section 13.4.3.22
1848h SWE_BCST_THROT Switch Engine Broadcast Throttling Register, Section 13.4.3.23
1849h SWE_ADMT_N_MEMBER Switch Engine Admit Non Member Register, Section 13.4.3.24
184Ah SWE_INGRESS_RATE_CFG Switch Engine Ingress Rate Configuration Register,
Section 13.4.3.25
184Bh SWE_INGRESS_RATE_CMD Switch Engine Ingress Rate Command Register,
Section 13.4.3.26
184Ch SWE_INGRESS_RATE_CMD_STS Switch Engine Ingress Rate Command Status Register,
Section 13.4.3.27
184Dh SWE_INGRESS_RATE_WR_DATA Switch Engine Ingress Rate Write Data Register,
Section 13.4.3.28
184Eh SWE_INGRESS_RATE_RD_DATA Switch Engine Ingress Rate Read Data Register,
Section 13.4.3.29
184Fh RESERVED Reserved for Future Use
1850h SWE_FILTERED_CNT_0 Switch Engine Port 0 Ingress Filtered Count Register,
Section 13.4.3.30
1851h SWE_FILTERED_CNT_1 Switch Engine Port 1 Ingress Filtered Count Register,
Section 13.4.3.31
1852h SWE_FILTERED_CNT_2 Switch Engine Port 2 Ingress Filtered Count Register,
Section 13.4.3.32
1853h-1854h RESERVED Reserved for Future Use
1855h SWE_INGRESS_REGEN_TBL_0 Switch Engine Port 0 Ingress VLAN Priority Regeneration
Register, Section 13.4.3.33
1856h SWE_INGRESS_REGEN_TBL_1 Switch Engine Port 1 Ingress VLAN Priority Regeneration
Register, Section 13.4.3.34
1857h SWE_INGRESS_REGEN_TBL_2 Switch Engine Port 2 Ingress VLAN Priority Regeneration
Register, Section 13.4.3.35
1858h SWE_LRN_DISCRD_CNT_0 Switch Engine Port 0 Learn Discard Count Register,
Section 13.4.3.36
1859h SWE_LRN_DISCRD_CNT_1 Switch Engine Port 1 Learn Discard Count Register,
Section 13.4.3.37
185Ah SWE_LRN_DISCRD_CNT_2 Switch Engine Port 2 Learn Discard Count Register,
Section 13.4.3.38
185Bh-187Fh RESERVED Reserved for Future Use
1880h SWE_IMR Switch Engine Interrupt Mask Register, Section 13.4.3.39
Table 13.14 Indirectly Accessible Switch Control and Status Registers (continued)
REGISTER # SYMBOL REGISTER NAME
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 237 Revision 1.5 (07-08-11)
DATASHEET
1881h SWE_IPR Switch Engine Interrupt Pending Register, Section 13.4.3.40
1882h-1BFFh RESERVED Reserved for Future Use
Buffer Manager (BM) CSRs
1C00h BM_CFG Buffer Manager Configuration Register, Section 13.4.4.1
1C01h BM_DROP_LVL Buffer Manager Drop Level Register, Section 13.4.4.2
1C02h BM_FC_PAUSE_LVL Buffer Manager Flow Control Pause Level Register,
Section 13.4.4.3
1C03h BM_FC_RESUME_LVL Buffer Manager Flow Control Resume Level Register,
Section 13.4.4.4
1C04h BM_BCST_LVL Buffer Manager Broadcast Buffer Level Register,
Section 13.4.4.5
1C05h BM_DRP_CNT_SRC_0 Buffer Manager Port 0 Drop Count Register, Section 13.4.4.6
1C06h BM_DRP_CNT_SRC_1 Buffer Manager Port 1 Drop Count Register, Section 13.4.4.7
1C07h BM_DRP_CNT_SRC_2 Buffer Manager Port 2 Drop Count Register, Section 13.4.4.8
1C08h BM_RST_STS Buffer Manager Reset Status Register, Section 13.4.4.9
1C09h BM_RNDM_DSCRD_TBL_CMD Buffer Manager Random Discard Table Command Register,
Section 13.4.4.10
1C0Ah BM_RNDM_DSCRD_TBL_WDATA Buffer Manager Random Discard Table Write Data Register,
Section 13.4.4.11
1C0Bh BM_RNDM_DSCRD_TBL_RDATA Buffer Manager Random Discard Table Read Data Register,
Section 13.4.4.12
1C0Ch BM_EGRSS_PORT_TYPE Buffer Manager Egress Port Type Register, Section 13.4.4.13
1C0Dh BM_EGRSS_RATE_00_01 Buffer Manager Port 0 Egress Rate Priority Queue 0/1 Register,
Section 13.4.4.14
1C0Eh BM_EGRSS_RATE_02_03 Buffer Manager Port 0 Egress Rate Priority Queue 2/3 Register,
Section 13.4.4.15
1C0Fh BM_EGRSS_RATE_10_11 Buffer Manager Port 1 Egress Rate Priority Queue 0/1 Register,
Section 13.4.4.16
1C10h BM_EGRSS_RATE_12_13 Buffer Manager Port 1 Egress Rate Priority Queue 2/3 Register,
Section 13.4.4.17
1C11h BM_EGRSS_RATE_20_21 Buffer Manager Port 2 Egress Rate Priority Queue 0/1 Register,
Section 13.4.4.18
1C12h BM_EGRSS_RATE_22_23 Buffer Manager Port 2 Egress Rate Priority Queue 2/3 Register,
Section 13.4.4.19
1C13h BM_VLAN_0 Buffer Manager Port 0 Default VLAN ID and Priority Register,
Section 13.4.4.20
1C14h BM_VLAN_1 Buffer Manager Port 1 Default VLAN ID and Priority Register,
Section 13.4.4.21
1C15h BM_VLAN_2 Buffer Manager Port 2 Default VLAN ID and Priority Register,
Section 13.4.4.22
Table 13.14 Indirectly Accessible Switch Control and Status Registers (continued)
REGISTER # SYMBOL REGISTER NAME
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1C16h BM_RATE_DRP_CNT_SRC_0 Buffer Manager Port 0 Ingress Rate Drop Count Register,
Section 13.4.4.23
1C17h BM_RATE_DRP_CNT_SRC_1 Buffer Manager Port 1 Ingress Rate Drop Count Register,
Section 13.4.4.24
1C18h BM_RATE_DRP_CNT_SRC_2 Buffer Manager Port 2 Ingress Rate Drop Count Register,
Section 13.4.4.25
1C19h-1C1FhRESERVED Reserved for Future Use
1C20h BM_IMR Buffer Manager Interrupt Mask Register, Section 13.4.4.26
1C21h BM_IPR Buffer Manager Interrupt Pending Register, Section 13.4.4.27
1C22h-FFFFhRESERVED Reserved for Future Use
Table 13.14 Indirectly Accessible Switch Control and Status Registers (continued)
REGISTER # SYMBOL REGISTER NAME
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13.4.1 General Switch CSRs
This section details the general Switch Fabric CSRs. These registers control the main reset and
interrupt functions of the Switch Fabric. A list of the general switch CSRs and their corresponding
register numbers is included in Table 13.14.
13.4.1.1 Switch Device ID Register (SW_DEV_ID)
This read-only register contains switch device ID information, including the device type, chip version
and revision codes.
Register #: 0000h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:24 RESERVED RO -
23:16 Device Type Code (DEVICE_TYPE) RO 03h
15:8 Chip Version Code (CHIP_VERSION) RO 04h
7:0 Revision Code (REVISION) RO 07h
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13.4.1.2 Switch Reset Register (SW_RESET)
This register contains the Switch Fabric global reset. Refer to Section 4.2, "Resets," on page 48 for
more information.
Register #: 0001h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:1 RESERVED RO -
0Switch Fabric Reset (SW_RESET)
This bit is the global switch fabric reset. All switch fabric blocks are affected.
This bit must be manually cleared.
WO 0b
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13.4.1.3 Switch Global Interrupt Mask Register (SW_IMR)
This read/write register contains the global interrupt mask for the Switch Fabric interrupts. All switch
related interrupts in the Switch Global Interrupt Pending Register (SW_IPR) may be masked via this
register. An interrupt is masked by setting the corresponding bit of this register. Clearing a bit will
unmask the interrupt. When an unmasked Switch Fabric interrupt is generated in the Switch Global
Interrupt Pending Register (SW_IPR), the interrupt will trigger the Switch Fabric Interrupt Event
(SWITCH_INT) bit in the Interrupt Status Register (INT_STS). Refer to Chapter 5, "System Interrupts,"
on page 62 for more information.
Register #: 0004h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:9 RESERVED RO -
8:7 RESERVED
Note: These bits must be written as 11b
R/W 11b
6Buffer Manager Interrupt Mask (BM)
When set, prevents the generation of Switch Fabric interrupts due to the
Buffer Manager via the Buffer Manager Interrupt Pending Register
(BM_IPR). The status bits in the Switch Global Interrupt Pending Register
(SW_IPR) register are not affected.
R/W 1b
5Switch Engine Interrupt Mask (SWE)
When set, prevents the generation of Switch Fabric interrupts due to the
Switch Engine via the Switch Engine Interrupt Pending Register (SWE_IPR).
The status bits in the Switch Global Interrupt Pending Register (SW_IPR)
register are not affected.
R/W 1b
4:3 RESERVED
Note: These bits must be written as 11b
R/W 11b
2Port 2 MAC Interrupt Mask (MAC_2)
When set, prevents the generation of Switch Fabric interrupts due to the
Port 2 MAC via the MAC_IPR_2 register (see Section 13.4.2.44, on
page 286). The status bits in the Switch Global Interrupt Pending Register
(SW_IPR) register are not affected.
R/W 1b
1Port 1 MAC Interrupt Mask (MAC_1)
When set, prevents the generation of Switch Fabric interrupts due to the
Port 1 MAC via the MAC_IPR_1 register (see Section 13.4.2.44, on
page 286). The status bits in the Switch Global Interrupt Pending Register
(SW_IPR) register are not affected.
R/W 1b
0Port 0 MAC Interrupt Mask (MAC_0)
When set, prevents the generation of Switch Fabric interrupts due to the
Port 0 MAC via the MAC_IPR_0 register (see Section 13.4.2.44, on
page 286). The status bits in the Switch Global Interrupt Pending Register
(SW_IPR) register are not affected.
R/W 1b
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13.4.1.4 Switch Global Interrupt Pending Register (SW_IPR)
This read-only register contains the pending global interrupts for the Switch Fabric. A set bit indicates
an unmasked bit in the corresponding Switch Fabric sub-system has been triggered. All switch related
interrupts in this register may be masked via the Switch Global Interrupt Mask Register (SW_IMR)
register. When an unmasked Switch Fabric interrupt is generated in this register, the interrupt will
trigger the Switch Fabric Interrupt Event (SWITCH_INT) bit in the Interrupt Status Register (INT_STS).
Refer to Chapter 5, "System Interrupts," on page 62 for more information.
Register #: 0005h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:7 RESERVED RO -
6Buffer Manager Interrupt (BM)
Set when any unmasked bit in the Buffer Manager Interrupt Pending
Register (BM_IPR) is triggered. This bit is cleared upon a read.
RC 0b
5Switch Engine Interrupt (SWE)
Set when any unmasked bit in the Switch Engine Interrupt Pending Register
(SWE_IPR) is triggered. This bit is cleared upon a read.
RC 0b
4:3 RESERVED RO -
2Port 2 MAC Interrupt (MAC_2)
Set when any unmasked bit in the MAC_IPR_2 register (see Section
13.4.2.44, on page 286) is triggered. This bit is cleared upon a read.
RC 0b
1Port 1 MAC Interrupt (MAC_1)
Set when any unmasked bit in the MAC_IPR_1 register (see Section
13.4.2.44, on page 286) is triggered. This bit is cleared upon a read.
RC 0b
0Port 0 MAC Interrupt (MAC_0)
Set when any unmasked bit in the MAC_IPR_0 register (see Section
13.4.2.44, on page 286) is triggered. This bit is cleared upon a read.
RC 0b
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13.4.2 Switch Port 0, Port 1, and Port 2 CSRs
This section details the switch Port 0, Port 1, and Port 2 CSRs. Each port provides a functionally
identical set of registers which allow for the configuration of port settings, interrupts, and the monitoring
of the various packet counters.
Because the Port 0, Port 1, and Port 2 CSRs are functionally identical, their register descriptions have
been consolidated. A lowercase “x” has been appended to the end of each switch port register name
in this section, where “x” should be replaced with “0”, “1”, or “2” for the Port 0, Port 1, or Port 2 registers
respectively. A list of the Switch Port 0, Port 1, and Port 2 registers and their corresponding register
numbers is included in Table 13.14.
13.4.2.1 Port x MAC Version ID Register (MAC_VER_ID_x)
This read-only register contains switch device ID information, including the device type, chip version
and revision codes.
Register #: Port0: 0400h Size: 32 bits
Port1: 0800h
Port2: 0C00h
BITS DESCRIPTION TYPE DEFAULT
31:12 RESERVED RO -
11:8 Device Type Code (DEVICE_TYPE) RO 5h
7:4 Chip Version Code (CHIP_VERSION) RO 8h
3:0 Revision Code (REVISION) RO 3h
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13.4.2.2 Port x MAC Receive Configuration Register (MAC_RX_CFG_x)
This read/write register configures the packet type passing parameters of the port.
Register #: Port0: 0401h Size: 32 bits
Port1: 0801h
Port2: 0C01h
BITS DESCRIPTION TYPE DEFAULT
31:8 RESERVED RO -
7RESERVED
Note: This bit must always be written as 0.
R/W 0b
6RESERVED RO -
5Enable Receive Own Transmit
When set, the switch port will receive its own transmission if it is looped back
from the PHY. Normally, this function is only used in Half Duplex PHY
loopback.
R/W 0b
4RESERVED RO -
3Jumbo2K
When set, the maximum packet size accepted is 2048 bytes. Statistics
boundaries are also adjusted.
R/W 0b
2RESERVED RO -
1Reject MAC Types
When set, MAC control frames (packets with a type field of 8808h) are
filtered. When cleared, MAC Control frames, other than MAC Control Pause
frames, are sent to the forwarding process. MAC Control Pause frames are
always consumed by the switch.
R/W 1b
0RX Enable
When set, the receive port is enabled. When cleared, the receive port is
disabled.
R/W 1b
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13.4.2.3 Port x MAC Receive Undersize Count Register (MAC_RX_UNDSZE_CNT_x)
This register provides a counter of undersized packets received by the port. The counter is cleared
upon being read.
Register #: Port0: 0410h Size: 32 bits
Port1: 0810h
Port2: 0C10h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX Undersize
Count of packets that have less than 64 byte and a valid FCS.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 115 hours.
RC 00000000h
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13.4.2.4 Port x MAC Receive 64 Byte Count Register (MAC_RX_64_CNT_x)
This register provides a counter of 64 byte packets received by the port. The counter is cleared upon
being read.
Note: A bad packet is defined as a packet that has an FCS or Symbol error. For this counter, a packet
that is not an integral number of bytes is rounded down to the nearest byte.
Register #: Port0: 0411h Size: 32 bits
Port1: 0811h
Port2: 0C11h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX 64 Bytes
Count of packets (including bad packets) that have exactly 64 bytes.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.2.5 Port x MAC Receive 65 to 127 Byte Count Register (MAC_RX_65_TO_127_CNT_x)
This register provides a counter of received packets between the size of 65 to 127 bytes. The counter
is cleared upon being read.
Note: A bad packet is defined as a packet that has an FCS or Symbol error. For this counter, a packet
that is not an integral number of bytes is rounded down to the nearest byte.
Register #: Port0: 0412h Size: 32 bits
Port1: 0812h
Port2: 0C12h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX 65 to 127 Bytes
Count of packets (including bad packets) that have between 65 and 127
bytes.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 487 hours.
RC 00000000h
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13.4.2.6 Port x MAC Receive 128 to 255 Byte Count Register (MAC_RX_128_TO_255_CNT_x)
This register provides a counter of received packets between the size of 128 to 255 bytes. The counter
is cleared upon being read.
Note: A bad packet is defined as a packet that has an FCS or Symbol error. For this counter, a packet
that is not an integral number of bytes is rounded down to the nearest byte.
Register #: Port0: 0413h Size: 32 bits
Port1: 0813h
Port2: 0C13h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX 128 to 255 Bytes
Count of packets (including bad packets) that have between 128 and 255
bytes.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 848 hours.
RC 00000000h
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13.4.2.7 Port x MAC Receive 256 to 511 Byte Count Register (MAC_RX_256_TO_511_CNT_x)
This register provides a counter of received packets between the size of 256 to 511 bytes. The counter
is cleared upon being read.
Note: A bad packet is defined as a packet that has an FCS or Symbol error. For this counter, a packet
that is not an integral number of bytes is rounded down to the nearest byte.
Register #: Port0: 0414h Size: 32 bits
Port1: 0814h
Port2: 0C14h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX 256 to 511 Bytes
Count of packets (including bad packets) that have between 256 and 511
bytes.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 1581 hours.
RC 00000000h
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13.4.2.8 Port x MAC Receive 512 to 1023 Byte Count Register (MAC_RX_512_TO_1023_CNT_x)
This register provides a counter of received packets between the size of 512 to 1023 bytes. The
counter is cleared upon being read.
Note: A bad packet is defined as a packet that has an FCS or Symbol error. For this counter, a packet
that is not an integral number of bytes is rounded down to the nearest byte.
Register #: Port0: 0415h Size: 32 bits
Port1: 0815h
Port2: 0C15h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX 512 to 1023 Bytes
Count of packets (including bad packets) that have between 512 and 1023
bytes.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 3047 hours.
RC 00000000h
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13.4.2.9 Port x MAC Receive 1024 to Max Byte Count Register (MAC_RX_1024_TO_MAX_CNT_x)
This register provides a counter of received packets between the size of 1024 to the maximum
allowable number bytes. The counter is cleared upon being read.
Note: A bad packet is defined as a packet that has an FCS or Symbol error. For this counter, a packet
with the maximum number of bytes that is not an integral number of bytes (e.g. a 1518 1/2
byte packet) is counted.
Register #: Port0: 0416h Size: 32 bits
Port1: 0816h
Port2: 0C16h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX 1024 to Max Bytes
Count of packets (including bad packets) that have between 1024 and the
maximum allowable number of bytes. The max number of bytes is 1518 for
untagged packets and 1522 for tagged packets. If the Jumbo2K bit is set in
the Port x MAC Receive Configuration Register (MAC_RX_CFG_x), the max
number of bytes is 2048.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 5979 hours.
RC 00000000h
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13.4.2.10 Port x MAC Receive Oversize Count Register (MAC_RX_OVRSZE_CNT_x)
This register provides a counter of received packets with a size greater than the maximum byte size.
The counter is cleared upon being read.
Note: For this counter, a packet with the maximum number of bytes that is not an integral number of
bytes (e.g. a 1518 1/2 byte packet) is not considered oversize.
Register #: Port0: 0417h Size: 32 bits
Port1: 0817h
Port2: 0C17h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX Oversize
Count of packets that have more than the maximum allowable number of
bytes and a valid FCS. The max number of bytes is 1518 for untagged
packets and 1522 for tagged packets. If the Jumbo2K bit is set in the Port
x MAC Receive Configuration Register (MAC_RX_CFG_x), the max number
of bytes is 2048.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 8813 hours.
RC 00000000h
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13.4.2.11 Port x MAC Receive OK Count Register (MAC_RX_PKTOK_CNT_x)
This register provides a counter of received packets that are or proper length and are free of errors.
The counter is cleared upon being read.
Note: A bad packet is one that has a FCS or Symbol error.
Register #: Port0: 0418h Size: 32 bits
Port1: 0818h
Port2: 0C18h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX OK
Count of packets that are of proper length and are free of errors.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.2.12 Port x MAC Receive CRC Error Count Register (MAC_RX_CRCERR_CNT_x)
This register provides a counter of received packets that with CRC errors. The counter is cleared upon
being read.
Register #: Port0: 0419h Size: 32 bits
Port1: 0819h
Port2: 0C19h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX CRC
Count of packets that have between 64 and the maximum allowable number
of bytes and have a bad FCS, but do not have an extra nibble. The max
number of bytes is 1518 for untagged packets and 1522 for tagged packets.
If the Jumbo2K bit is set in the Port x MAC Receive Configuration Register
(MAC_RX_CFG_x), the max number of bytes is 2048.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 137 hours.
RC 00000000h
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13.4.2.13 Port x MAC Receive Multicast Count Register (MAC_RX_MULCST_CNT_x)
This register provides a counter of valid received packets with a multicast destination address. The
counter is cleared upon being read.
Note: A bad packet is one that has a FCS or Symbol error.
Register #: Port0: 041Ah Size: 32 bits
Port1: 081Ah
Port2: 0C1Ah
BITS DESCRIPTION TYPE DEFAULT
31:0 RX Multicast
Count of good packets (proper length and free of errors), including MAC
control frames, that have a multicast destination address (not including
broadcasts).
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.2.14 Port x MAC Receive Broadcast Count Register (MAC_RX_BRDCST_CNT_x)
This register provides a counter of valid received packets with a broadcast destination address. The
counter is cleared upon being read.
Note: A bad packet is one that has a FCS or Symbol error.
Register #: Port0: 041Bh Size: 32 bits
Port1: 081Bh
Port2: 0C1Bh
BITS DESCRIPTION TYPE DEFAULT
31:0 RX Broadcast
Count of valid packets (proper length and free of errors) that have a
broadcast destination address.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.2.15 Port x MAC Receive Pause Frame Count Register (MAC_RX_PAUSE_CNT_x)
This register provides a counter of valid received pause frame packets. The counter is cleared upon
being read.
Note: A bad packet is one that has a FCS or Symbol error.
Register #: Port0: 041Ch Size: 32 bits
Port1: 081Ch
Port2: 0C1Ch
BITS DESCRIPTION TYPE DEFAULT
31:0 RX Pause Frame
Count of valid packets (proper length and free of errors) that have a type
field of 8808h and an op-code of 0001(Pause).
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.2.16 Port x MAC Receive Fragment Error Count Register (MAC_RX_FRAG_CNT_x)
This register provides a counter of received packets of less than 64 bytes and a FCS error. The counter
is cleared upon being read.
Register #: Port0: 041Dh Size: 32 bits
Port1: 081Dh
Port2: 0C1Dh
BITS DESCRIPTION TYPE DEFAULT
31:0 RX Fragment
Count of packets that have less than 64 bytes and a FCS error.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 115 hours.
RC 00000000h
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13.4.2.17 Port x MAC Receive Jabber Error Count Register (MAC_RX_JABB_CNT_x)
This register provides a counter of received packets with greater than the maximum allowable number
of bytes and a FCS error. The counter is cleared upon being read.
Note: For this counter, a packet with the maximum number of bytes that is not an integral number of
bytes (e.g. a 1518 1/2 byte packet) and contains a FCS error is not considered jabber and is
not counted here.
Register #: Port0: 041Eh Size: 32 bits
Port1: 081Eh
Port2: 0C1Eh
BITS DESCRIPTION TYPE DEFAULT
31:0 RX Jabber
Count of packets that have more than the maximum allowable number of
bytes and a FCS error. The max number of bytes is 1518 for untagged
packets and 1522 for tagged packets. If the Jumbo2K bit is set in the Port
x MAC Receive Configuration Register (MAC_RX_CFG_x), the max number
of bytes is 2048.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 8813 hours.
RC 00000000h
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13.4.2.18 Port x MAC Receive Alignment Error Count Register (MAC_RX_ALIGN_CNT_x)
This register provides a counter of received packets with 64 bytes to the maximum allowable, and a
FCS error. The counter is cleared upon being read.
Note: For this counter, a packet with the maximum number of bytes that is not an integral number of
bytes (e.g. a 1518 1/2 byte packet) and a FCS error is considered an alignment error and is
counted.
Register #: Port0: 041Fh Size: 32 bits
Port1: 081Fh
Port2: 0C1Fh
BITS DESCRIPTION TYPE DEFAULT
31:0 RX Alignment
Count of packets that have between 64 bytes and the maximum allowable
number of bytes and are not byte aligned and have a bad FCS. The max
number of bytes is 1518 for untagged packets and 1522 for tagged packets.
If the Jumbo2K bit is set in the Port x MAC Receive Configuration Register
(MAC_RX_CFG_x), the max number of bytes is 2048.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.2.19 Port x MAC Receive Packet Length Count Register (MAC_RX_PKTLEN_CNT_x)
This register provides a counter of total bytes received. The counter is cleared upon being read.
Note: If necessary, for oversized packets, the packet is either truncated at 1518 bytes (untagged,
Jumbo2K=0), 1522 bytes (tagged, Jumbo2K=0), or 2048 bytes (Jumbo2K=1). If this occurs,
the byte count recorded is 1518, 1522, or 2048, respectively. The Jumbo2K bit is located in
the Port x MAC Receive Configuration Register (MAC_RX_CFG_x).
Note: A bad packet is one that has an FCS or Symbol error. For this counter, a packet that is not an
integral number of bytes (e.g. a 1518 1/2 byte packet) is rounded down to the nearest byte.
Register #: Port0: 0420h Size: 32 bits
Port1: 0820h
Port2: 0C20h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX Bytes
Count of total bytes received (including bad packets).
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 5.8 hours.
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13.4.2.20 Port x MAC Receive Good Packet Length Count Register (MAC_RX_GOODPKTLEN_CNT_x)
This register provides a counter of total bytes received in good packets. The counter is cleared upon
being read.
Note: A bad packet is one that has an FCS or Symbol error.
Register #: Port0: 0421h Size: 32 bits
Port1: 0821h
Port2: 0C21h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX Good Bytes
Count of total bytes received in good packets (proper length and free of
errors).
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 5.8 hours.
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13.4.2.21 Port x MAC Receive Symbol Error Count Register (MAC_RX_SYMBOL_CNT_x)
This register provides a counter of received packets with a symbol error. The counter is cleared upon
being read.
Register #: Port0: 0422h Size: 32 bits
Port1: 0822h
Port2: 0C22h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX Symbol
Count of packets that had a receive symbol error.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 115 hours.
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13.4.2.22 Port x MAC Receive Control Frame Count Register (MAC_RX_CTLFRM_CNT_x)
This register provides a counter of good packets with a type field of 8808h. The counter is cleared
upon being read.
Note: A bad packet is one that has an FCS or Symbol error.
Register #: Port0: 0423h Size: 32 bits
Port1: 0823h
Port2: 0C23h
BITS DESCRIPTION TYPE DEFAULT
31:0 RX Control Frame
Count of good packets (proper length and free of errors) that have a type
field of 8808h.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
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13.4.2.23 Port x MAC Transmit Configuration Register (MAC_TX_CFG_x)
This read/write register configures the transmit packet parameters of the port.
Register #: Port0: 0440h Size: 32 bits
Port1: 0840h
Port2: 0C40h
BITS DESCRIPTION TYPE DEFAULT
31:8 RESERVED RO -
7MAC Counter Test
When set, TX and RX counters that normally clear to 0 when read, will be
set to 7FFF_FFFCh when read with the exception of the Port x MAC
Receive Packet Length Count Register (MAC_RX_PKTLEN_CNT_x), Port x
MAC Transmit Packet Length Count Register (MAC_TX_PKTLEN_CNT_x),
and Port x MAC Receive Good Packet Length Count Register
(MAC_RX_GOODPKTLEN_CNT_x) counters which will be set to
7FFF_FF80h.
R/W 0b
6:2 IFG Config
These bits control the transmit inter-frame gap.
IFG bit times = (IFG Config *4) + 12
Note: IFG Config values less than 15 are unsupported.
R/W 10101b
1TX Pad Enable
When set, packets shorter than 64 bytes are padded with zeros if needed
and a FCS is appended. Packets that are 60 bytes or less will become 64
bytes. Packets that are 61, 62, and 63 bytes will become 65, 66, and 67
bytes respectively.
R/W 1b
0TX Enable
When set, the transmit port is enabled. When cleared, the transmit port is
disabled.
R/W 1b
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13.4.2.24 Port x MAC Transmit Flow Control Settings Register (MAC_TX_FC_SETTINGS_x)
This read/write register configures the flow control settings of the port.
Register #: Port0: 0441h Size: 32 bits
Port1: 0841h
Port2: 0C41h
BITS DESCRIPTION TYPE DEFAULT
31:18 RESERVED RO -
17:16 Backoff Reset RX/TX
Half duplex-only. Determines when the truncated binary exponential backoff
attempts counter is reset.
00 = Reset on successful transmission (IEEE standard)
01 = Reset on successful reception
1X = Reset on either successful transmission or reception
R/W 00b
15:0 Pause Time Value
The value that is inserted into the transmitted pause packet when the switch
wants to “XOFF” its link partner.
R/W FFFFh
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13.4.2.25 Port x MAC Transmit Deferred Count Register (MAC_TX_DEFER_CNT_x)
This register provides a counter deferred packets. The counter is cleared upon being read.
Register #: Port0: 0451h Size: 32 bits
Port1: 0851h
Port2: 0C51h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX Deferred
Count of packets that were available for transmission but were deferred on
the first transmit attempt due to network traffic (either on receive or prior
transmission). This counter is not incremented on collisions. This counter is
incremented only in half-duplex operation.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
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13.4.2.26 Port x MAC Transmit Pause Count Register (MAC_TX_PAUSE_CNT_x)
This register provides a counter of transmitted pause packets. The counter is cleared upon being read.
Register #: Port0: 0452h Size: 32 bits
Port1: 0852h
Port2: 0C52h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX Pause
Count of pause packets transmitted.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
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13.4.2.27 Port x MAC Transmit OK Count Register (MAC_TX_PKTOK_CNT_x)
This register provides a counter of successful transmissions. The counter is cleared upon being read.
Register #: Port0: 0453h Size: 32 bits
Port1: 0853h
Port2: 0C53h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX OK
Count of successful transmissions. Undersize packets are not included in
this count.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
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13.4.2.28 Port x MAC Transmit 64 Byte Count Register (MAC_TX_64_CNT_x)
This register provides a counter of 64 byte packets transmitted by the port. The counter is cleared
upon being read.
Register #: Port0: 0454h Size: 32 bits
Port1: 0854h
Port2: 0C54h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX 64 Bytes
Count of packets that have exactly 64 bytes.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
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13.4.2.29 Port x MAC Transmit 65 to 127 Byte Count Register (MAC_TX_65_TO_127_CNT_x)
This register provides a counter of transmitted packets between the size of 65 to 127 bytes. The
counter is cleared upon being read.
Register #: Port0: 0455h Size: 32 bits
Port1: 0855h
Port2: 0C55h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX 65 to 127 Bytes
Count of packets that have between 65 and 127 bytes.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 487 hours.
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13.4.2.30 Port x MAC Transmit 128 to 255 Byte Count Register (MAC_TX_128_TO_255_CNT_x)
This register provides a counter of transmitted packets between the size of 128 to 255 bytes. The
counter is cleared upon being read.
Register #: Port0: 0456h Size: 32 bits
Port1: 0856h
Port2: 0C56h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX 128 to 255 Bytes
Count of packets that have between 128 and 255 bytes.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 848 hours.
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13.4.2.31 Port x MAC Transmit 256 to 511 Byte Count Register (MAC_TX_256_TO_511_CNT_x)
This register provides a counter of transmitted packets between the size of 256 to 511 bytes. The
counter is cleared upon being read.
Register #: Port0: 0457h Size: 32 bits
Port1: 0857h
Port2: 0C57h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX 256 to 511 Bytes
Count of packets that have between 256 and 511 bytes.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 1581 hours.
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13.4.2.32 Port x MAC Transmit 512 to 1023 Byte Count Register (MAC_TX_512_TO_1023_CNT_x)
This register provides a counter of transmitted packets between the size of 512 to 1023 bytes. The
counter is cleared upon being read.
Register #: Port0: 0458h Size: 32 bits
Port1: 0858h
Port2: 0C58h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX 512 to 1023 Bytes
Count of packets that have between 512 and 1023 bytes.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 3047 hours.
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13.4.2.33 Port x MAC Transmit 1024 to Max Byte Count Register (MAC_TX_1024_TO_MAX_CNT_x)
This register provides a counter of transmitted packets between the size of 1024 to the maximum
allowable number bytes. The counter is cleared upon being read.
Register #: Port0: 0459h Size: 32 bits
Port1: 0859h
Port2: 0C59h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX 1024 to Max Bytes
Count of packets that have more than 1024 bytes.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 5979 hours.
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13.4.2.34 Port x MAC Transmit Undersize Count Register (MAC_TX_UNDSZE_CNT_x)
This register provides a counter of undersized packets transmitted by the port. The counter is cleared
upon being read.
Register #: Port0: 045Ah Size: 32 bits
Port1: 085Ah
Port2: 0C5Ah
BITS DESCRIPTION TYPE DEFAULT
31:0 TX Undersize
Count of packets that have less than 64 bytes.
Note: This condition could occur when TX padding is disabled and a tag
is removed.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 458 hours.
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13.4.2.35 Port x MAC Transmit Packet Length Count Register (MAC_TX_PKTLEN_CNT_x)
This register provides a counter of total bytes transmitted. The counter is cleared upon being read.
Register #: Port0: 045Ch Size: 32 bits
Port1: 085Ch
Port2: 0C5Ch
BITS DESCRIPTION TYPE DEFAULT
31:0 TX Bytes
Count of total bytes transmitted (does not include bytes from collisions, but
does include bytes from Pause packets).
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 5.8 hours.
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13.4.2.36 Port x MAC Transmit Broadcast Count Register (MAC_TX_BRDCST_CNT_x)
This register provides a counter of transmitted broadcast packets. The counter is cleared upon being
read.
Register #: Port0: 045Dh Size: 32 bits
Port1: 085Dh
Port2: 0C5Dh
BITS DESCRIPTION TYPE DEFAULT
31:0 TX Broadcast
Count of broadcast packets transmitted.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
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13.4.2.37 Port x MAC Transmit Multicast Count Register (MAC_TX_MULCST_CNT_x)
This register provides a counter of transmitted multicast packets. The counter is cleared upon being
read.
Register #: Port0: 045Eh Size: 32 bits
Port1: 085Eh
Port2: 0C5Eh
BITS DESCRIPTION TYPE DEFAULT
31:0 TX Multicast
Count of multicast packets transmitted including MAC Control Pause frames.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
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13.4.2.38 Port x MAC Transmit Late Collision Count Register (MAC_TX_LATECOL_CNT_x)
This register provides a counter of transmitted packets which experienced a late collision. The counter
is cleared upon being read.
Register #: Port0: 045Fh Size: 32 bits
Port1: 085Fh
Port2: 0C5Fh
BITS DESCRIPTION TYPE DEFAULT
31:0 TX Late Collision
Count of transmitted packets that experienced a late collision. This counter
is incremented only in half-duplex operation.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
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13.4.2.39 Port x MAC Transmit Excessive Collision Count Register (MAC_TX_EXCCOL_CNT_x)
This register provides a counter of transmitted packets which experienced 16 collisions. The counter
is cleared upon being read.
Register #: Port0: 0460h Size: 32 bits
Port1: 0860h
Port2: 0C60h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX Excessive Collision
Count of transmitted packets that experienced 16 collisions. This counter is
incremented only in half-duplex operation.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 1466 hours.
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13.4.2.40 Port x MAC Transmit Single Collision Count Register (MAC_TX_SNGLECOL_CNT_x)
This register provides a counter of transmitted packets which experienced exactly 1 collision. The
counter is cleared upon being read.
Register #: Port0: 0461h Size: 32 bits
Port1: 0861h
Port2: 0C61h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX Excessive Collision
Count of transmitted packets that experienced exactly 1 collision. This
counter is incremented only in half-duplex operation.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 573 hours.
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13.4.2.41 Port x MAC Transmit Multiple Collision Count Register (MAC_TX_MULTICOL_CNT_x)
This register provides a counter of transmitted packets which experienced between 2 and 15 collisions.
The counter is cleared upon being read.
Register #: Port0: 0462h Size: 32 bits
Port1: 0862h
Port2: 0C62h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX Excessive Collision
Count of transmitted packets that experienced between 2 and 15 collisions.
This counter is incremented only in half-duplex operation.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 664 hours.
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13.4.2.42 Port x MAC Transmit Total Collision Count Register (MAC_TX_TOTALCOL_CNT_x)
This register provides a counter of total collisions including late collisions. The counter is cleared upon
being read.
Register #: Port0: 0463h Size: 32 bits
Port1: 0863h
Port2: 0C63h
BITS DESCRIPTION TYPE DEFAULT
31:0 TX Total Collision
Total count of collisions including late collisions. This counter is incremented
only in half-duplex operation.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 92 hours.
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13.4.2.43 Port x MAC Interrupt Mask Register (MAC_IMR_x)
This register contains the Port x interrupt mask. Port x related interrupts in the Port x MAC Interrupt
Pending Register (MAC_IPR_x) may be masked via this register. An interrupt is masked by setting the
corresponding bit of this register. Clearing a bit will unmask the interrupt. Refer to Chapter 5, "System
Interrupts," on page 62 for more information.
Note: There are no possible Port x interrupt conditions available. This register exists for future use,
and should be configured as indicated for future compatibility.
Register #: Port0: 0480h Size: 32 bits
Port1: 0880h
Port2: 0C80h
BITS DESCRIPTION TYPE DEFAULT
31:8 RESERVED RO -
7:0 RESERVED
Note: These bits must be written as 11h
R/W 11h
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13.4.2.44 Port x MAC Interrupt Pending Register (MAC_IPR_x)
This read-only register contains the pending Port x interrupts. A set bit indicates an interrupt has been
triggered. All interrupts in this register may be masked via the Port x MAC Interrupt Pending Register
(MAC_IPR_x) register. Refer to Chapter 5, "System Interrupts," on page 62 for more information.
Note: There are no possible Port x interrupt conditions available. This register exists for future use.
Register #: Port0: 0481h Size: 32 bits
Port1: 0881h
Port2: 0C81h
BITS DESCRIPTION TYPE DEFAULT
31:0 RESERVED RO -
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13.4.3 Switch Engine CSRs
This section details the Switch Engine related CSRs. These registers allow configuration and
monitoring of the various Switch Engine components including the ALR, VLAN, Port VID, and
DIFFSERV tables. A list of the general switch CSRs and their corresponding register numbers is
included in Table 13.14.
13.4.3.1 Switch Engine ALR Command Register (SWE_ALR_CMD)
This register is used to manually read and write MAC addresses from/into the ALR table.
For a read access, the Switch Engine ALR Read Data 0 Register (SWE_ALR_RD_DAT_0) and Switch
Engine ALR Read Data 1 Register (SWE_ALR_RD_DAT_1) should be read following the setting of the
Get First Entry bit or Get Next Entry bit of this register.
For write access, the Switch Engine ALR Write Data 0 Register (SWE_ALR_WR_DAT_0) and Switch
Engine ALR Write Data 1 Register (SWE_ALR_WR_DAT_1) registers should first be written with the
MAC address, followed by the setting of the Make Entry bit of this register. The Make Pending bit in
the Switch Engine ALR Command Status Register (SWE_ALR_CMD_STS) register indicates when the
command is finished.
Refer to Chapter 6, "Switch Fabric," on page 67 for more information.
Register #: 1800h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:3 RESERVED RO -
2Make Entry
When set, the contents of SWE_ALR_WR_DAT_0 and
SWE_ALR_WR_DAT_1 are written into the ALR table. The ALR logic
determines the location where the entry is written. This command can also
be used to change or delete a previously written or automatically learned
entry. This bit has no affect when written low. This bit must be cleared once
the ALR Make command is completed, which can be determined by the
Make Pending bit in the Switch Engine ALR Command Status Register
(SWE_ALR_CMD_STS) register.
R/W 0b
1Get First Entry
When set, the ALR read pointer is reset to the beginning of the ALR table
and the ALR table is searched for the first valid entry, which is loaded into
the SWE_ALR_RD_DAT_0 and SWE_ALR_RD_DAT_1 registers. The bit
has no affect when written low. This bit must be cleared after it is set.
R/W 0b
0Get Next Entry
When set, the next valid entry in the ALR MAC address table is loaded into
the SWE_ALR_RD_DAT_0 and SWE_ALR_RD_DAT_1 registers. This bit
has no affect when written low. This bit must be cleared after it is set.
R/W 0b
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13.4.3.2 Switch Engine ALR Write Data 0 Register (SWE_ALR_WR_DAT_0)
This register is used in conjunction with the Switch Engine ALR Write Data 1 Register
(SWE_ALR_WR_DAT_1) and contains the first 32 bits of ALR data to be manually written via the Make
Entry command in the Switch Engine ALR Command Register (SWE_ALR_CMD).
Register #: 1801h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 MAC Address
This field contains the first 32 bits of the ALR entry that will be written into
the ALR table. These bits correspond to the first 32 bits of the MAC address.
Bit 0 holds the LSB of the first byte (the multicast bit).
R/W 00000000h
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13.4.3.3 Switch Engine ALR Write Data 1 Register (SWE_ALR_WR_DAT_1)
This register is used in conjunction with the Switch Engine ALR Write Data 0 Register
(SWE_ALR_WR_DAT_0) and contains the last 32 bits of ALR data to be manually written via the Make
Entry command in the Switch Engine ALR Command Register (SWE_ALR_CMD).
Register #: 1802h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:27 RESERVED RO -
26 Valid
When set, this bit makes the entry valid. It can be cleared to invalidate a
previous entry that contained the specified MAC address.
R/W 0b
25 Age/Override
This bit is used by the aging and forwarding processes.
If the Static bit of this register is cleared, this bit should be set so that the
entry will age in the normal amount of time.
If the Static bit is set, this bit is used as a port state override bit. When set,
packets received with a destination address that matches the MAC address
in the SWE_ALR_WR_DAT_1 and SWE_ALR_WR_DAT_0 registers will be
forwarded regardless of the port state (except the Disabled state) of the
ingress or egress port(s). This is typically used to allow the reception of
BPDU packets in the non-forwarding state.
R/W 0b
24 Static
When this bit is set, this entry will not be removed by the aging process
and/or be changed by the learning process. When this bit is cleared, this
entry will be automatically removed after 5 to 10 minutes of inactivity.
Inactivity is defined as no packets being received with a source address that
matches this MAC address.
Note: This bit is normally set when adding manual entries.
R/W 0b
23 Filter
When set, packets with a destination address that matches this MAC
address will be filtered.
R/W 0b
22 Priority Enable
When set, this bit enables usage of the Priority field for this MAC address
entry. When clear, the Priority field is not used.
R/W 0b
21:19 Priority
These bits specify the priority that is used for packets with a destination
address that matches this MAC address. This priority is only used if both the
Priority Enable bit of this register and the DA Highest Priority bit of the
Switch Engine Global Ingress Configuration Register
(SWE_GLOBAL_INGRSS_CFG) are set.
R/W 000b
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18:16 Port
These bits indicate the port(s) associated with this MAC address. When bit
18 is cleared, a single port is selected. When bit 18 is set, multiple ports are
selected.
R/W 000b
15:0 MAC Address
These field contains the last 16 bits of the ALR entry that will be written into
the ALR table. They correspond to the last 16 bits of the MAC address. Bit
15 holds the MSB of the last byte (the last bit on the wire). The first 32 bits
of the MAC address are located in the Switch Engine ALR Write Data 0
Register (SWE_ALR_WR_DAT_0).
R/W 0000h
BITS DESCRIPTION TYPE DEFAULT
VALUE ASSOCIATED PORT(S)
000 Port 0
001 Port 1
010 Port 2
011 RESERVED
100 Port 0 and Port 1
101 Port 0 and Port 2
110 Port 1 and Port 2
111 Port 0, Port 1, and Port 2
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13.4.3.4 Switch Engine ALR Read Data 0 Register (SWE_ALR_RD_DAT_0)
This register is used in conjunction with the Switch Engine ALR Read Data 1 Register
(SWE_ALR_RD_DAT_1) to read the ALR table. It contains the first 32 bits of the ALR entry and is
loaded via the Get First Entry or Get Next Entry commands in the Switch Engine ALR Command
Register (SWE_ALR_CMD). This register is only valid when either of the Valid or End of Table bits in
the Switch Engine ALR Read Data 1 Register (SWE_ALR_RD_DAT_1) are set.
Register #: 1805h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 MAC Address
This field contains the first 32 bits of the ALR entry. These bits correspond
to the first 32 bits of the MAC address. Bit 0 holds the LSB of the first byte
(the multicast bit).
RO 00000000h
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13.4.3.5 Switch Engine ALR Read Data 1 Register (SWE_ALR_RD_DAT_1)
This register is used in conjunction with the Switch Engine ALR Read Data 0 Register
(SWE_ALR_RD_DAT_0) to read the ALR table. It contains the last 32 bits of the ALR entry and is
loaded via the Get First Entry or Get Next Entry commands in the Switch Engine ALR Command
Register (SWE_ALR_CMD). This register is only valid when either of the Valid or End of Table bits are
set.
Register #: 1806h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:27 RESERVED RO -
26 Valid
This bit is cleared when the Get First Entry or Get Next Entry bits of the
Switch Engine ALR Command Register (SWE_ALR_CMD) are written. This
bit is set when a valid entry is found in the ALR table. This bit stays cleared
when the top of the ALR table is reached without finding an entry.
RO 0b
25 End of Table
This bit indicates that the end of the ALR table has been reached and further
Get Next Entry commands are not required.
Note: The Valid bit may or may not be set when the end of the table is
reached.
RO 0b
24 Static
Indicates that this entry will not be removed by the aging process. When this
bit is cleared, this entry will be automatically removed after 5 to 10 minutes
of inactivity. Inactivity is defined as no packets being received with a source
address that matches this MAC address.
RO 0b
23 Filter
When set, indicates that packets with a destination address that matches
this MAC address will be filtered.
RO 0b
22 Priority Enable
Indicates whether or not the usage of the Priority field is enabled for this
MAC address entry.
RO 0b
21:19 Priority
These bits specify the priority that is used for packets with a destination
address that matches this MAC address. This priority is only used if both the
Priority Enable bit of this register and the DA Highest Priority bit in the
Switch Engine Global Ingress Configuration Register
(SWE_GLOBAL_INGRSS_CFG) are set.
RO 000b
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18:16 Port
These bits indicate the port(s) associated with this MAC address. When bit
18 is cleared, a single port is selected. When bit 18 is set, multiple ports are
selected.
RO 000b
15:0 MAC Address
These field contains the last 16 bits of the ALR entry. They correspond to
the last 16 bits of the MAC address. Bit 15 holds the MSB of the last byte
(the last bit on the wire). The first 32 bits of the MAC address are located
in the Switch Engine ALR Read Data 0 Register (SWE_ALR_RD_DAT_0).
RO 0000h
BITS DESCRIPTION TYPE DEFAULT
VALUE ASSOCIATED PORT(S)
000 Port 0
001 Port 1
010 Port 2
011 RESERVED
100 Port 0 and Port 1
101 Port 0 and Port 2
110 Port 1 and Port 2
111 Port 0, Port 1, and Port 2
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13.4.3.6 Switch Engine ALR Command Status Register (SWE_ALR_CMD_STS)
This register indicates the current ALR command status.
Note 13.77 The default value of this bit is 0 immediately following any Switch Fabric reset and then
self-sets to 1 once the ALR table is initialized.
Register #: 1808h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:2 RESERVED RO -
1ALR Init Done
When set, indicates that the ALR table has finished being initialized by the
reset process. The initialization is performed upon any reset that resets the
Switch Fabric. The initialization takes approximately 20uS. During this time,
any received packet will be dropped. Software should monitor this bit before
writing any of the ALR tables or registers.
RO
SS
Note 13.77
0Make Pending
When set, indicates that the Make Entry command is taking place. This bit
is cleared once the Make Entry command has finished.
RO
SC
0b
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13.4.3.7 Switch Engine ALR Configuration Register (SWE_ALR_CFG)
This register controls the ALR aging timer duration.
Register #: 1809h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:1 RESERVED RO -
0ALR Age Test
When set, this bit decreases the aging timer from 5 minutes to 50mS.
R/W 0b
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13.4.3.8 Switch Engine VLAN Command Register (SWE_VLAN_CMD)
This register is used to read and write the VLAN or Port VID tables. A write to this address performs
the specified access.
For a read access, the Operation Pending bit in the Switch Engine VLAN Command Status Register
(SWE_VLAN_CMD_STS) indicates when the command is finished. The Switch Engine VLAN Read
Data Register (SWE_VLAN_RD_DATA) can then be read.
For a write access, the Switch Engine VLAN Write Data Register (SWE_VLAN_WR_DATA) register
should be written first. The Operation Pending bit in the Switch Engine VLAN Command Status
Register (SWE_VLAN_CMD_STS) indicates when the command is finished.
Register #: 180Bh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:6 RESERVED RO -
5VLAN RnW
This bit specifies a read(1) or a write(0) command.
R/W 0b
4PVIDnVLAN
When set, this bit selects the Port VID table. When cleared, this bit selects
the VLAN table.
R/W 0b
3:0 VLAN/Port
This field specifies the VLAN(0-15) or port(0-2) to be read or written.
Note: Values outside of the valid range may cause unexpected results.
R/W 0h
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13.4.3.9 Switch Engine VLAN Write Data Register (SWE_VLAN_WR_DATA)
This register is used write the VLAN or Port VID tables.
Register #: 180Ch Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:18 RESERVED RO -
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17:0 Port Default VID and Priority
When the port VID table is selected (PVIDnVLAN=1 of the Switch Engine
VLAN Command Register (SWE_VLAN_CMD)), bits 11:0 of this field specify
the default VID for the port and bits 14:12 specify the default priority. All
other bits of this field are reserved. These bits are used when a packet is
received without a VLAN tag or with a NULL VLAN ID. The default VID is
also used when the 802.1Q VLAN Disable bit is set. The default priority is
also used when no other priority choice is selected. By default, the VID for
all three ports is 1 and the priority for all three ports is 0.
Note: Values of 0 and FFFh should not be used since they are special
VLAN IDs per the IEEE 802.3Q specification.
VLAN Data
When the VLAN table is selected (PVIDnVLAN=0 of the Switch Engine
VLAN Command Register (SWE_VLAN_CMD)), the bits form the VLAN
table entry as follows:
R/W 0b
BITS DESCRIPTION TYPE DEFAULT
BITS DESCRIPTION DEFAULT
17 Member Port 2
Indicates the configuration of Port 2 for this VLAN entry.
1 = Member - Packets with a VID that matches this entry
are allowed on ingress. The port is a member of the
broadcast domain on egress.
0 = Not a Member - Packets with a VID that matches this
entry are filtered on ingress unless the Admit Non Member
bit in the Switch Engine Admit Non Member Register
(SWE_ADMT_N_MEMBER) is set for this port. The port is
not a member of the broadcast domain on egress.
0b
16 Un-Tag Port 2
When this bit is set, packets with a VID that matches this
entry will have their tag removed when re-transmitted on
Port 2 when it is designated as a Hybrid port via the Buffer
Manager Egress Port Type Register
(BM_EGRSS_PORT_TYPE).
0b
15 Member Port 1
See description for Member Port 2.
0b
14 Un-Tag Port 1
See description for Un-Tag Port 2.
0b
13 Member Port 0
See description for Member Port 2.
0b
12 Un-Tag Port 0
See description for Un-Tag Port 2.
0b
11:0 VID
These bits specify the VLAN ID associated with this VLAN
entry.
To disable a VLAN entry, a value of 0 should be used.
Note: A value of 0 is considered a NULL VLAN and
should not normally be used other than to
disable a VLAN entry.
Note: A value of 3FFh is considered reserved by IEEE
802.1Q and should not be used.
000h
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13.4.3.10 Switch Engine VLAN Read Data Register (SWE_VLAN_RD_DATA)
This register is used to read the VLAN or Port VID tables.
Register #: 180Eh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:18 RESERVED RO -
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17:0 Port Default VID and Priority
When the port VID table is selected (PVIDnVLAN=1 of the Switch Engine
VLAN Command Register (SWE_VLAN_CMD)), bits 11:0 of this field specify
the default VID for the port and bits 14:12 specify the default priority. All
other bits of this field are reserved. These bits are used when a packet is
received without a VLAN tag or with a NULL VLAN ID. The default VID is
also used when the 802.1Q VLAN Disable bit is set. The default priority is
also used when no other priority choice is selected. By default, the VID for
all three ports is 1 and the priority for all three ports is 0.
Note: Values of 0 and FFFh should not be used since they are special
VLAN IDs per the IEEE 802.3Q specification.
VLAN Data
When the VLAN table is selected (PVIDnVLAN=0 of the Switch Engine
VLAN Command Register (SWE_VLAN_CMD)), the bits form the VLAN
table entry as follows:
RO 00000h
BITS DESCRIPTION TYPE DEFAULT
BITS DESCRIPTION DEFAULT
17 Member Port 2
Indicates the configuration of Port 2 for this VLAN entry.
1 = Member - Packets with a VID that matches this entry
are allowed on ingress. The port is a member of the
broadcast domain on egress.
0 = Not a Member - Packets with a VID that matches this
entry are filtered on ingress unless the Admit Non Member
bit in the Switch Engine Admit Non Member Register
(SWE_ADMT_N_MEMBER) is set for this port. The port is
not a member of the broadcast domain on egress.
0b
16 Un-Tag Port 2
When this bit is set, packets with a VID that matches this
entry will have their tag removed when re-transmitted on
Port 2 when it is designated as a Hybrid port via the Buffer
Manager Egress Port Type Register
(BM_EGRSS_PORT_TYPE)
0b
15 Member Port 1
See description for Member Port 2.
0b
14 Un-Tag Port 1
See description for Un-Tag Port 2.
0b
13 Member Port 0
See description for Member Port 2.
0b
12 Un-Tag Port 0
See description for Un-Tag Port 2.
0b
11:0 VID
These bits specify the VLAN ID associated with this VLAN
entry.
To disable a VLAN entry, a value of 0 should be used.
Note: A value of 0 is considered a NULL VLAN and
should not normally be used other than to
disable a VLAN entry.
Note: A value of 3FFh is considered reserved by IEEE
802.1Q and should not be used.
000h
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13.4.3.11 Switch Engine VLAN Command Status Register (SWE_VLAN_CMD_STS)
This register indicates the current VLAN command status.
Register #: 1810h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:1 RESERVED RO -
0Operation Pending
When set, this bit indicates that the read or write command is taking place.
This bit is cleared once the command has finished.
RO
SC
0b
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13.4.3.12 Switch Engine DIFFSERV Table Command Register (SWE_DIFFSERV_TBL_CFG)
This register is used to read and write the DIFFSERV table. A write to this address performs the
specified access. This table is used to map the received IP ToS/CS to a priority.
For a read access, the Operation Pending bit in the Switch Engine DIFFSERV Table Command Status
Register (SWE_DIFFSERV_TBL_CMD_STS) indicates when the command is finished. The Switch
Engine DIFFSERV Table Read Data Register (SWE_DIFFSERV_TBL_RD_DATA) can then be read.
For a write access, the Switch Engine DIFFSERV Table Write Data Register
(SWE_DIFFSERV_TBL_WR_DATA) register should be written first. The Operation Pending bit in the
Switch Engine DIFFSERV Table Command Status Register (SWE_DIFFSERV_TBL_CMD_STS)
indicates when the command is finished.
Register #: 1811h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:8 RESERVED RO -
7DIFFSERV Table RnW
This bit specifies a read(1) or a write(0) command.
R/W 0b
6RESERVED RO -
5:0 DIFFSERV Table Index
This field specifies the ToS/CS entry that is accessed.
R/W 0h
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13.4.3.13 Switch Engine DIFFSERV Table Write Data Register (SWE_DIFFSERV_TBL_WR_DATA)
This register is used to write the DIFFSERV table. The DIFFSERV table is not initialized upon reset
on power-up. If DIFFSERV is enabled, the full table should be initialized by the host.
Register #: 1812h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:3 RESERVED RO -
2:0 DIFFSERV Priority
These bits specify the assigned receive priority for IP packets with a ToS/CS
field that matches this index.
R/W 000b
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13.4.3.14 Switch Engine DIFFSERV Table Read Data Register (SWE_DIFFSERV_TBL_RD_DATA)
This register is used to read the DIFFSERV table.
Register #: 1813h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:3 RESERVED RO -
2:0 DIFFSERV Priority
These bits specify the assigned receive priority for IP packets with a ToS/CS
field that matches this index.
RO 000b
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13.4.3.15 Switch Engine DIFFSERV Table Command Status Register (SWE_DIFFSERV_TBL_CMD_STS)
This register indicates the current DIFFSERV command status.
Register #: 1814h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:1 RESERVED RO -
0Operation Pending
When set, this bit indicates that the read or write command is taking place.
This bit is cleared once the command has finished.
RO
SC
0b
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13.4.3.16 Switch Engine Global Ingress Configuration Register (SWE_GLOBAL_INGRSS_CFG)
This register is used to configure the global ingress rules.
Register #: 1840h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED RO -
15 802.1Q VLAN Disable
When set, the VID from the VLAN tag is ignored and the per port default
VID (PVID) is used for purposes of VLAN rules. This does not affect the
packet tag on egress.
R/W 0b
14 Use Tag
When set, the priority from the VLAN tag is enabled as a transmit priority
queue choice.
R/W 0b
13 Allow Monitor Echo
When set, monitoring packets are allowed to be echoed back to the source
port. When cleared, monitoring packets, like other packets, are never sent
back to the source port.
This bit is useful when the monitor port wishes to receive it’s own IGMP
packets.
R/W 0b
12:10 IGMP Monitor Port
This field is the port bit map where IPv4 IGMP packets are sent.
R/W 0b
9Use IP
When set, the IPv4 TOS or IPv6 SC field is enabled as a transmit priority
queue choice.
R/W 0b
8RESERVED R/W -
7Enable IGMP Monitoring
When set, IPv4 IGMP packets are monitored and sent to the IGMP monitor
port.
R/W 0b
6SWE Counter Test
When this bit is set the Switch Engine counters that normally clear to 0 when
read will be set to 7FFF_FFFCh when read.
R/W 0b
5DA Highest Priority
When this bit is set and the priority enable bit in the ALR table for the
destination MAC address is set, the transmit priority queue that is selected
is taken from the ALR Priority bits (see the Switch Engine ALR Read Data
1 Register (SWE_ALR_RD_DAT_1)).
R/W 0b
4Filter Multicast
When this bit is set, packets with a multicast destination address are filtered
if the address is not found in the ALR table. Broadcasts are not included in
this filter.
R/W 0b
3Drop Unknown
When this bit is set, packets with a unicast destination address are filtered
if the address is not found in the ALR table.
R/W 0b
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2Use Precedence
When the priority is taken from an IPV4 packet (enabled via the Use IP bit),
this bit selects between precedence bits in the TOS octet or the DIFFSERV
table.
When set, IPv4 packets will use the precedence bits in the TOS octet to
select the transmit priority queue. When cleared, IPv4 packets will use the
DIFFSERV table to select the transmit priority queue.
R/W 1b
1VL Higher Priority
When this bit is set and VLAN priority is enabled (via the Use Tag bit), the
priority from the VLAN tag has higher priority than the IP TOS/SC field.
R/W 1b
0VLAN Enable
When set, VLAN ingress rules are enabled.
R/W 0b
BITS DESCRIPTION TYPE DEFAULT
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13.4.3.17 Switch Engine Port Ingress Configuration Register (SWE_PORT_INGRSS_CFG)
This register is used to configure the per port ingress rules.
Register #: 1841h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:6 RESERVED RO -
5:3 Enable Learning on Ingress
When set, source addresses are learned when a packet is received on the
corresponding port and the corresponding Port State in the Switch Engine
Port State Register (SWE_PORT_STATE) is set to forwarding or learning.
There is one enable bit per ingress port. Bits 5,4,3 correspond to switch
ports 2,1,0 respectively.
R/W 111b
2:0 Enable Membership Checking
When set, VLAN membership is checked when a packet is received on the
corresponding port.
The packet will be filtered if the ingress port is not a member of the VLAN
(unless the Admit Non Member bit is set for the port in the Switch Engine
Admit Non Member Register (SWE_ADMT_N_MEMBER))
For destination addresses that are found in the ALR table, the packet will be
filtered if the egress port is not a member of the VLAN (for destination
addresses that are not found in the ALR table only the ingress port is
checked for membership).
The VLAN Enable bit in the Switch Engine Global Ingress Configuration
Register (SWE_GLOBAL_INGRSS_CFG) needs to be set for these bits to
have an affect.
There is one enable bit per ingress port. Bits 2,1,0 correspond to switch
ports 2,1,0 respectively.
R/W 000b
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13.4.3.18 Switch Engine Admit Only VLAN Register (SWE_ADMT_ONLY_VLAN)
This register is used to configure the per port ingress rule for allowing only VLAN tagged packets.
Register #: 1842h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:3 RESERVED RO -
2:0 Admit Only VLAN
When set, untagged and priority tagged packets are filtered.
The VLAN Enable bit in the Switch Engine Global Ingress Configuration
Register (SWE_GLOBAL_INGRSS_CFG) needs to be set for these bits to
have an affect.
There is one enable bit per ingress port. Bits 2,1,0 correspond to switch
ports 2,1,0 respectively.
R/W 000b
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13.4.3.19 Switch Engine Port State Register (SWE_PORT_STATE)
This register is used to configure the per port spanning tree state.
Register #: 1843h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:6 RESERVED RO -
5:4 Port State Port 2
These bits specify the spanning tree port states for Port 2.
00 = Forwarding
01 = Listening/Blocking
10 = Learning
11 = Disabled
R/W 00b
3:2 Port State Port 1
These bits specify the spanning tree port states for Port 1.
00 = Forwarding
01 = Listening/Blocking
10 = Learning
11 = Disabled
R/W 00b
1:0 Port State Port 0
These bits specify the spanning tree port states for Port 0.
00 = Forwarding
01 = Listening/Blocking
10 = Learning
11 = Disabled
R/W 00b
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13.4.3.20 Switch Engine Priority to Queue Register (SWE_PRI_TO_QUE)
This register specifies the Traffic Class table that maps the packet priority into the egress queues.
Register #: 1845h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED RO -
15:14 Priority 7 traffic Class
These bits specify the egress queue that is used for packets with a priority
of 7.
R/W 11b
13:12 Priority 6 traffic Class
These bits specify the egress queue that is used for packets with a priority
of 6.
R/W 11b
11:10 Priority 5 traffic Class
These bits specify the egress queue that is used for packets with a priority
of 5.
R/W 10b
9:8 Priority 4 traffic Class
These bits specify the egress queue that is used for packets with a priority
of 4.
R/W 10b
7:6 Priority 3 traffic Class
These bits specify the egress queue that is used for packets with a priority
of 3.
R/W 01b
5:4 Priority 2 traffic Class
These bits specify the egress queue that is used for packets with a priority
of 2.
R/W 00b
3:2 Priority 1 traffic Class
These bits specify the egress queue that is used for packets with a priority
of 1.
R/W 00b
1:0 Priority 0 traffic Class
These bits specify the egress queue that is used for packets with a priority
of 0.
R/W 01b
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13.4.3.21 Switch Engine Port Mirroring Register (SWE_PORT_MIRROR)
This register is used to configure port mirroring.
Register #: 1846h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:9 RESERVED RO -
8Enable RX Mirroring Filtered
When set, packets that would normally have been filtered are included in the
receive mirroring function and are sent only to the sniffer port. When
cleared, filtered packets are not mirrored.
Note: The Ingress Filtered Count Registers will still count these packets
as filtered and the Switch Engine Interrupt Pending Register
(SWE_IPR) will still register a drop interrupt.
R/W 0b
7:5 Sniffer Port
These bits specify the sniffer port that transmits packets that are monitored.
Bits 7,6,5 correspond to switch ports 2,1,0 respectively.
Note: Only one port should be set as the sniffer.
R/W 00b
4:2 Mirrored Port
These bits specify if a port is to be mirrored. Bits 4,3,2 correspond to switch
ports 2,1,0 respectively.
Note: Multiple ports can be set as mirrored.
R/W 00b
1Enable RX Mirroring
This bit enables packets received on the mirrored ports to be also sent to
the sniffer port.
R/W 0b
0Enable TX Mirroring
This bit enables packets transmitted on the mirrored ports to be also sent to
the sniffer port.
R/W 0b
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13.4.3.22 Switch Engine Ingress Port Type Register (SWE_INGRSS_PORT_TYP)
This register is used to enable the special tagging mode used to determine the destination port based
on the VLAN tag contents.
Register #: 1847h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:6 RESERVED RO -
5:4 Ingress Port Type Port 2
A setting of 11b enables the usage of the VLAN tag to specify the packet
destination. All other values disable this feature.
R/W 00b
3:2 Ingress Port Type Port 1
A setting of 11b enables the usage of the VLAN tag to specify the packet
destination. All other values disable this feature.
R/W 00b
1:0 Ingress Port Type Port 0
A setting of 11b enables the usage of the VLAN tag to specify the packet
destination. All other values disable this feature.
R/W 00b
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13.4.3.23 Switch Engine Broadcast Throttling Register (SWE_BCST_THROT)
This register configures the broadcast input rate throttling.
Register #: 1848h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:27 RESERVED RO -
26 Broadcast Throttle Enable Port 2
This bit enables broadcast input rate throttling on Port 2.
R/W 0b
25:18 Broadcast Throttle Level Port 2
These bits specify the number of bytes x 64 allowed to be received per
every 1.72mS interval.
R/W 02h
17 Broadcast Throttle Enable Port 1
This bit enables broadcast input rate throttling on Port 1.
R/W 0b
16:9 Broadcast Throttle Level Port 1
These bits specify the number of bytes x 64 allowed to be received per
every 1.72mS interval.
R/W 02h
8Broadcast Throttle Enable Port 0
This bit enables broadcast input rate throttling on Port 0.
R/W 0b
7:0 Broadcast Throttle Level Port 0
These bits specify the number of bytes x 64 allowed to be received per
every 1.72mS interval.
R/W 02h
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13.4.3.24 Switch Engine Admit Non Member Register (SWE_ADMT_N_MEMBER)
This register is used to allow access to a VLAN even if the ingress port is not a member.
Register #: 1849h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:3 RESERVED RO -
2:0 Admit Non Member
When set, a received packet is accepted even if the ingress port is not a
member of the destination VLAN. The VLAN still must be active in the
switch.
There is one bit per ingress port. Bits 2,1,0 correspond to switch ports 2,1,0
respectively.
R/W 000b
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13.4.3.25 Switch Engine Ingress Rate Configuration Register (SWE_INGRSS_RATE_CFG)
This register, along with the settings accessible via the Switch Engine Ingress Rate Command Register
(SWE_INGRSS_RATE_CMD), is used to configure the ingress rate metering/coloring.
Register #: 184Ah Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:3 RESERVED RO -
2:1 Rate Mode
These bits configure the rate metering/coloring mode.
00 = Source Port & Priority
01 = Source Port Only
10 = Priority Only
11 = RESERVED
R/W 00b
0Ingress Rate Enable
When set, ingress rates are metered and packets are colored and dropped
if necessary.
R/W 0b
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13.4.3.26 Switch Engine Ingress Rate Command Register (SWE_INGRSS_RATE_CMD)
This register is used to indirectly read and write the ingress rate metering/color table registers. A write
to this address performs the specified access.
For a read access, the Operation Pending bit in the Switch Engine Ingress Rate Command Status
Register (SWE_INGRSS_RATE_CMD_STS) indicates when the command is finished. The Switch
Engine Ingress Rate Read Data Register (SWE_INGRSS_RATE_RD_DATA) can then be read.
For a write access, the Switch Engine Ingress Rate Write Data Register
(SWE_INGRSS_RATE_WR_DATA) should be written first. The Operation Pending bit in the Switch
Engine Ingress Rate Command Status Register (SWE_INGRSS_RATE_CMD_STS) indicates when the
command is finished.
For details on 16-bit wide Ingress Rate Table registers indirectly accessible by this register, see
Section 13.4.3.26.1 below.
Register #: 184Bh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:8 RESERVED RO -
7Ingress Rate RnW
These bits specify a read(1) or write(0) command.
R/W 0b
6:5 Type
These bits select between the ingress rate metering/color table registers as
follows:
00 = RESERVED
01 = Committed Information Rate Registers (uses CIS Address field)
10 = Committed Burst Register
11 = Excess Burst Register
R/W 00b
4:0 CIR Address
These bits select one of the 24 Committed Information Rate registers.
When Rate Mode is set to Source Port & Priority in the Switch Engine
Ingress Rate Configuration Register (SWE_INGRSS_RATE_CFG), the first
set of 8 registers (CIR addresses 0-7) are for to Port 0, the second set of 8
registers (CIR addresses 8-15) are for Port 1, and the third set of registers
(CIR addresses 16-23) are for Port 2. Priority 0 is the lower register of each
set (e.g. 0, 8, and 16).
When Rate Mode is set to Source Port Only, the first register (CIR address
0) is for Port 0, the second register (CIR address 1) is for Port 1, and the
third register (CIR address 2) is for Port 2.
When Rate Mode is set to Priority Only, the first register (CIR address 0) is
for priority 0, the second register (CIR address 1) is for priority 1, and so
forth up to priority 23.
Note: Values outside of the valid range may cause unexpected results.
R/W 0h
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13.4.3.26.1 INGRESS RATE TABLE REGISTERS
The ingress rate metering/color table consists of 24 Committed Information Rate (CIR) registers (one
per port/priority), a Committed Burst Size register, and an Excess Burst Size register. All metering/color
table registers are 16-bits in size and are accessed indirectly via the Switch Engine Ingress Rate
Command Register (SWE_INGRSS_RATE_CMD). Descriptions of these registers are detailed in
Table 13.15 below.
Table 13.15 Metering/Color Table Register Descriptions
DESCRIPTION TYPE DEFAULT
Excess Burst Size
This register specifies the maximum excess burst size in bytes. Bursts larger than
this value that exceed the excess data rate are dropped.
Note: Either this value or the Committed Burst Size should be set larger than or
equal to the largest possible packet expected.
Note: All of the Excess Burst token buckets are initialized to this default value.
If a lower value is programmed into this register, the token buckets will
need to be normally depleted below this value before this value has any
affect on limiting the token bucket maximum values.
This register is 16-bits wide.
R/W 0600h
Committed Burst Size
This register specifies the maximum committed burst size in bytes. Bursts larger
than this value that exceed the committed data rate are subjected to random
dropping.
Note: Either this value or the Excess Burst Size should be set larger than or
equal to the largest possible packet expected.
Note: All of the Committed Burst token buckets are initialized to this default
value. If a lower value is programmed into this register, the token buckets
will need to be normally depleted below this value before this value has
any affect on limiting the token bucket maximum values.
This register is 16-bits wide.
R/W 0600h
Committed Information Rate (CIR)
These registers specify the committed data rate for the port/priority pair. The rate
is specified in time per byte. The time is this value plus 1 times 20nS.
There are 24 of these registers each 16-bits wide.
R/W 0014h
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13.4.3.27 Switch Engine Ingress Rate Command Status Register (SWE_INGRSS_RATE_CMD_STS)
This register indicates the current ingress rate command status.
Register #: 184Ch Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:1 RESERVED RO -
0Operation Pending
When set, indicates that the read or write command is taking place. This bit
is cleared once the command has finished.
RO
SC
0b
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13.4.3.28 Switch Engine Ingress Rate Write Data Register (SWE_INGRSS_RATE_WR_DATA)
This register is used to write the ingress rate table registers.
Register #: 184Dh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED RO -
15:0 Data
This is the data to be written to the ingress rate table registers as specified
in the Switch Engine Ingress Rate Command Register
(SWE_INGRSS_RATE_CMD). Refer to Section 13.4.3.26.1, "Ingress Rate
Table Registers," on page 318 for details on these registers.
R/W 0000h
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13.4.3.29 Switch Engine Ingress Rate Read Data Register (SWE_INGRSS_RATE_RD_DATA)
This register is used to read the ingress rate table registers.
Register #: 184Eh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED RO -
15:0 Data
This is the read data from the ingress rate table registers as specified in the
Switch Engine Ingress Rate Command Register
(SWE_INGRSS_RATE_CMD). Refer to Section 13.4.3.26.1, "Ingress Rate
Table Registers," on page 318 for details on these registers.
RO 0000h
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13.4.3.30 Switch Engine Port 0 Ingress Filtered Count Register (SWE_FILTERED_CNT_0)
This register counts the number of packets filtered at ingress on Port 0. This count includes packets
filtered due to broadcast throttling but does not include packets dropped due to ingress rate limiting
(which are counted separately).
Register #: 1850h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Filtered
This field is a count of packets filtered at ingress and is cleared when read.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.3.31 Switch Engine Port 1 Ingress Filtered Count Register (SWE_FILTERED_CNT_1)
This register counts the number of packets filtered at ingress on Port 1. This count includes packets
filtered due to broadcast throttling but does not include packets dropped due to ingress rate limiting
(which are counted separately).
Register #: 1851h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Filtered
This field is a count of packets filtered at ingress and is cleared when read.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.3.32 Switch Engine Port 2 Ingress Filtered Count Register (SWE_FILTERED_CNT_2)
This register counts the number of packets filtered at ingress on Port 2. This count includes packets
filtered due to broadcast throttling but does not include packets dropped due to ingress rate limiting
(which are counted separately).
Register #: 1852h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Filtered
This field is a count of packets filtered at ingress and is cleared when read.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.3.33 Switch Engine Port 0 Ingress VLAN Priority Regeneration Table Register
(SWE_INGRSS_REGEN_TBL_0)
This register provides the ability to map the received VLAN priority to a regenerated priority. The
regenerated priority is used in determining the output priority queue. By default, the regenerated priority
is identical to the received priority.
Register #: 1855h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:24 RESERVED RO -
23:21 Regen7
These bits specify the regenerated priority for received priority 7.
R/W 7h
20:18 Regen6
These bits specify the regenerated priority for received priority 6.
R/W 6h
17:15 Regen5
These bits specify the regenerated priority for received priority 5.
R/W 5h
14:12 Regen4
These bits specify the regenerated priority for received priority 4.
R/W 4h
11:9 Regen3
These bits specify the regenerated priority for received priority 3.
R/W 3h
8:6 Regen2
These bits specify the regenerated priority for received priority 2.
R/W 2h
5:3 Regen1
These bits specify the regenerated priority for received priority 1.
R/W 1h
2:0 Regen0
These bits specify the regenerated priority for received priority 0.
R/W 0h
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13.4.3.34 Switch Engine Port 1 Ingress VLAN Priority Regeneration Table Register
(SWE_INGRSS_REGEN_TBL_1)
This register provides the ability to map the received VLAN priority to a regenerated priority. The
regenerated priority is used in determining the output priority queue. By default, the regenerated priority
is identical to the received priority.
Register #: 1856h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:24 RESERVED RO -
23:21 Regen7
These bits specify the regenerated priority for received priority 7.
R/W 7h
20:18 Regen6
These bits specify the regenerated priority for received priority 6.
R/W 6h
17:15 Regen5
These bits specify the regenerated priority for received priority 5.
R/W 5h
14:12 Regen4
These bits specify the regenerated priority for received priority 4.
R/W 4h
11:9 Regen3
These bits specify the regenerated priority for received priority 3.
R/W 3h
8:6 Regen2
These bits specify the regenerated priority for received priority 2.
R/W 2h
5:3 Regen1
These bits specify the regenerated priority for received priority 1.
R/W 1h
2:0 Regen0
These bits specify the regenerated priority for received priority 0.
R/W 0h
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13.4.3.35 Switch Engine Port 2 Ingress VLAN Priority Regeneration Table Register
(SWE_INGRSS_REGEN_TBL_2)
This register provides the ability to map the received VLAN priority to a regenerated priority. The
regenerated priority is used in determining the output priority queue. By default, the regenerated priority
is identical to the received priority.
Register #: 1857h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:24 RESERVED RO -
23:21 Regen7
These bits specify the regenerated priority for received priority 7.
R/W 7h
20:18 Regen6
These bits specify the regenerated priority for received priority 6.
R/W 6h
17:15 Regen5
These bits specify the regenerated priority for received priority 5.
R/W 5h
14:12 Regen4
These bits specify the regenerated priority for received priority 4.
R/W 4h
11:9 Regen3
These bits specify the regenerated priority for received priority 3.
R/W 3h
8:6 Regen2
These bits specify the regenerated priority for received priority 2.
R/W 2h
5:3 Regen1
These bits specify the regenerated priority for received priority 1.
R/W 1h
2:0 Regen0
These bits specify the regenerated priority for received priority 0.
R/W 0h
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13.4.3.36 Switch Engine Port 0 Learn Discard Count Register (SWE_LRN_DISCRD_CNT_0)
This register counts the number of MAC addresses on Port 0 that were not learned or were overwritten
by a different address due to address table space limitations.
Register #: 1858h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Learn Discard
This field is a count of MAC addresses not learned or overwritten and is
cleared when read.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.3.37 Switch Engine Port 1 Learn Discard Count Register (SWE_LRN_DISCRD_CNT_1)
This register counts the number of MAC addresses on Port 1 that were not learned or were overwritten
by a different address due to address table space limitations.
Register #: 1859h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Learn Discard
This field is a count of MAC addresses not learned or overwritten and is
cleared when read.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.3.38 Switch Engine Port 2 Learn Discard Count Register (SWE_LRN_DISCRD_CNT_2)
This register counts the number of MAC addresses on Port 2 that were not learned or were overwritten
by a different address due to address table space limitations.
Register #: 185Ah Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Learn Discard
This field is a count of MAC addresses not learned or overwritten and is
cleared when read.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.3.39 Switch Engine Interrupt Mask Register (SWE_IMR)
This register contains the Switch Engine interrupt mask, which masks the interrupts in the Switch
Engine Interrupt Pending Register (SWE_IPR). All Switch Engine interrupts are masked by setting the
Interrupt Mask bit. Clearing this bit will unmask the interrupts. Refer to Chapter 5, "System Interrupts,"
on page 62 for more information.
Register #: 1880h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:1 RESERVED RO -
0Interrupt Mask
When set, this bit masks interrupts from the Switch Engine. The status bits
in the Switch Engine Interrupt Pending Register (SWE_IPR) are not
affected.
R/W 1b
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13.4.3.40 Switch Engine Interrupt Pending Register (SWE_IPR)
This register contains the Switch Engine interrupt status. The status is double buffered. All interrupts
in this register may be masked via the Switch Engine Interrupt Mask Register (SWE_IMR) register.
Refer to Chapter 5, "System Interrupts," on page 62 for more information.
Register #: 1881h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:15 RESERVED RO -
14:11 Drop Reason B
When the Set B Valid bit is set, these bits indicate the reason a packet was
dropped per the table below:
RC 0h
BIT
VALUES DESCRIPTION
0000 Admit Only VLAN was set and the packet was untagged or priority tagged.
0001 The destination address was not in the ALR table (unknown or broadcast),
Enable Membership Checking on ingress was set, Admit Non Member was
cleared and the source port was not a member of the incoming VLAN.
0010 The destination address was found in the ALR table but the source port was
not in the forwarding state.
0011 The destination address was found in the ALR table but the destination port
was not in the forwarding state.
0100 The destination address was found in the ALR table but Enable Membership
Checking on ingress was set and the destination port was not a member of the
incoming VLAN.
0101 The destination address was found in the ALR table but the Enable
Membership Checking on ingress was set, Admit Non Member was cleared and
the source port was not a member of the incoming VLAN.
0110 Drop Unknown was set and the destination address was a unicast but not in
the ALR table.
0111 Filter Multicast was set and the destination address was a multicast and not in
the ALR table.
1000 The packet was a broadcast but exceeded the Broadcast Throttling limit.
1001 The destination address was not in the ALR table (unknown or broadcast) and
the source port was not in the forwarding state.
1010 The destination address was found in the ALR table but the source and
destination ports were the same.
1011 The destination address was found in the ALR table and the Filter bit was set
for that address.
1100 RESERVED.
1101 RESERVED
1110 A packet was received with a VLAN ID of FFFh.
1111 RESERVED
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10:9 Source Port B
When the Set B Valid bit is set, these bits indicate the source port on which
the packet was dropped.
00 = Port 0
01 = Port 1
10 = Port 2
11 = RESERVED
RC 00b
8Set B Valid
When set, bits 14:9 are valid.
RC 0b
7:4 Drop Reason A
When the Set A Valid bit is set, these bits indicate the reason a packet was
dropped. See the Drop Reason B description above for definitions of each
value of this field.
RC 0h
3:2 Source port A
When the Set A Valid bit is set, these bits indicate the source port on which
the packet was dropped.
00 = Port 0
01 = Port 1
10 = Port 2
11 = RESERVED
RC 00b
1Set A Valid
When set, bits 7:2 are valid.
RC 0b
0Interrupt Pending
When set, a packet dropped event(s) is indicated.
RC 0b
BITS DESCRIPTION TYPE DEFAULT
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13.4.4 Buffer Manager CSRs
This section details the Buffer Manager (BM) registers. These registers allow configuration and
monitoring of the switch buffer levels and usage. A list of the general switch CSRs and their
corresponding register numbers is included in Table 13.14.
13.4.4.1 Buffer Manager Configuration Register (BM_CFG)
This register enables egress rate pacing and ingress rate discarding.
Register #: 1C00h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:7 RESERVED RO -
6BM Counter Test
When this bit is set, Buffer Manager (BM) counters that normally clear to 0
when read, will be set to 7FFF_FFFC when read.
R/W 0b
5Fixed Priority Queue Servicing
When set, output queues are serviced with a fixed priority ordering. When
cleared, output queues are serviced with a weighted round robin ordering.
R/W 0b
4:2 Egress Rate Enable
When set, egress rate pacing is enabled. Bits 4,3,2 correspond to switch
ports 2,1,0 respectively.
R/W 0b
1Drop on Yellow
When this bit is set, packets that exceed the Ingress Committed Burst Size
(colored Yellow) are subjected to random discard.
Note: See Section 13.4.3.26, "Switch Engine Ingress Rate Command
Register (SWE_INGRSS_RATE_CMD)," on page 317 for
information on configuring the Ingress Committed Burst Size.
R/W 0b
0Drop on Red
When this bit is set, packets that exceed the Ingress Excess Burst Size
(colored Red) are discarded.
Note: See Section 13.4.3.26, "Switch Engine Ingress Rate Command
Register (SWE_INGRSS_RATE_CMD)," on page 317 for
information on configuring the Ingress Excess Burst Size.
R/W 0b
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13.4.4.2 Buffer Manager Drop Level Register (BM_DROP_LVL)
This register configures the overall buffer usage limits.
Register #: 1C01h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED RO -
15:8 Drop Level Low
These bits specify the buffer limit that can be used per ingress port during
times when 2 or 3 ports are active.
Each buffer is 128 bytes.
Note: A port is “active” when 36 buffers are in use for that port.
R/W 49h
7:0 Drop Level High
These bits specify the buffer limit that can be used per ingress port during
times when 1 port is active.
Each buffer is 128 bytes.
Note: A port is “active” when 36 buffers are in use for that port.
R/W 64h
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13.4.4.3 Buffer Manager Flow Control Pause Level Register (BM_FC_PAUSE_LVL)
This register configures the buffer usage level when a Pause frame or backpressure is sent.
Register #: 1C02h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED RO -
15:8 Pause Level Low
These bits specify the buffer usage level during times when 2 or 3 ports are
active.
Each buffer is 128 bytes.
Note: A port is “active” when 36 buffers are in use for that port.
R/W 21h
7:0 Pause Level High
These bits specify the buffer usage level during times when 1 port is active.
Each buffer is 128 bytes.
Note: A port is “active” when 36 buffers are in use for that port.
R/W 3Ch
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13.4.4.4 Buffer Manager Flow Control Resume Level Register (BM_FC_RESUME_LVL)
This register configures the buffer usage level when a Pause frame with a pause value of 1 is sent.
Register #: 1C03h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:16 RESERVED RO -
15:8 Resume Level Low
These bits specify the buffer usage level during times when 2 or 3 ports are
active.
Each buffer is 128 bytes.
Note: A port is “active” when 36 buffers are in use for that port.
R/W 03h
7:0 Resume Level High
These bits specify the buffer usage level during times when 0 or 1 ports are
active.
Each buffer is 128 bytes.
Note: A port is “active” when 36 buffers are in use for that port.
R/W 07h
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13.4.4.5 Buffer Manager Broadcast Buffer Level Register (BM_BCST_LVL)
This register configures the buffer usage limits for broadcasts, multicasts, and unknown unicasts.
Register #: 1C04h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:8 RESERVED RO -
7:0 Broadcast Drop Level
These bits specify the maximum number of buffers that can be used by
broadcasts, multicasts, and unknown unicasts.
Each buffer is 128 bytes.
R/W 31h
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13.4.4.6 Buffer Manager Port 0 Drop Count Register (BM_DRP_CNT_SRC_0)
This register counts the number of packets dropped by the Buffer Manager that were received on Port
0. This count includes packets dropped due to buffer space limits and ingress rate limit discarding (Red
and random Yellow dropping).
Register #: 1C05h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Dropped Count
These bits count the number of dropped packets received on Port 0 and is
cleared when read.
Note: The counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.4.7 Buffer Manager Port 1 Drop Count Register (BM_DRP_CNT_SRC_1)
This register counts the number of packets dropped by the Buffer Manager that were received on Port
1. This count includes packets dropped due to buffer space limits and ingress rate limit discarding (Red
and random Yellow dropping).
Register #: 1C06h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Dropped Count
These bits count the number of dropped packets received on Port 1 and is
cleared when read.
Note: The counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.4.8 Buffer Manager Port 2 Drop Count Register (BM_DRP_CNT_SRC_2)
This register counts the number of packets dropped by the Buffer Manager that were received on Port
2. This count includes packets dropped due to buffer space limits and ingress rate limit discarding (Red
and random Yellow dropping).
Register #: 1C07h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Dropped Count
These bits count the number of dropped packets received on Port 2 and is
cleared when read.
Note: The counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.4.9 Buffer Manager Reset Status Register (BM_RST_STS)
This register indicates when the Buffer Manager has been initialized by the reset process.
Note 13.78 The default value of this bit is 0 immediately following any Switch Fabric reset and then
self-sets to 1 once the ALR table is initialized.
Register #: 1C08h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:1 RESERVED RO -
0BM Ready
When set, indicates the Buffer Manager tables have finished being initialized
by the reset process. The initialization is performed upon any reset that
resets the Switch Fabric.
RO
SS
Note 13.78
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13.4.4.10 Buffer Manager Random Discard Table Command Register (BM_RNDM_DSCRD_TBL_CMD)
This register is used to read and write the Random Discard Weight table. A write to this address
performs the specified access. This table is used to set the packet drop probability verses the buffer
usage.
For a read access, the Buffer Manager Random Discard Table Read Data Register
(BM_RNDM_DSCRD_TBL_RDATA) can be read following a write to this register.
For a write access, the Buffer Manager Random Discard Table Write Data Register
(BM_RNDM_DSCRD_TBL_WDATA) should be written before writing this register.
Register #: 1C09h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:5 RESERVED RO -
4Random Discard Weight Table RnW
Specifies a read (1) or a write (0) command.
R/W 0b
3:0 Random Discard Weight Table Index
Specifies the buffer usage range that is accessed.
There are a total of 16 probability entries. Each entry corresponds to a range
of the number of buffers used by the ingress port. The ranges are structured
to give more resolution towards the lower buffer usage end.
R/W 0h
BIT
VALUES BUFFER USAGE LEVEL
0000 0 to 7
0001 8 to 15
0010 16 to 23
0011 24 to 31
0100 32 to 39
0101 40 to 47
0110 48 to 55
0111 56 to 63
1000 64 to 79
1001 80 to 95
1010 96 to 111
1011 112 to 127
1100 128 to 159
1101 160 to 191
1110 192 to 223
1111 224 to 255
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13.4.4.11 Buffer Manager Random Discard Table Write Data Register (BM_RNDM_DSCRD_TBL_WDATA)
This register is used to write the Random Discard Weight table.
Note: The Random Discard Weight table is not initialized upon reset or power-up. If a random discard
is enabled, the full table should be initialized by the host.
Register #: 1C0Ah Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:10 RESERVED RO -
9:0 Drop Probability
These bits specify the discard probability of a packet that has been colored
Yellow by the ingress metering. The probability is given in 1/1024’s. For
example, a setting of 1 is one in 1024, or approximately 0.1%. A setting of
all ones (1023) is 1023 in 1024, or approximately 99.9%.
There are a total of 16 probability entries. Each entry corresponds to a range
of the number of buffers used by the ingress port, as specified in Section
13.4.4.10, "Buffer Manager Random Discard Table Command Register
(BM_RNDM_DSCRD_TBL_CMD)".
R/W 000h
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13.4.4.12 Buffer Manager Random Discard Table Read Data Register (BM_RNDM_DSCRD_TBL_RDATA)
This register is used to read the Random Discard Weight table.
Register #: 1C0Bh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:10 RESERVED RO -
9:0 Drop Probability
These bits specify the discard probability of a packet that has been colored
Yellow by the ingress metering. The probability is given in 1/1024’s. For
example, a setting of 1 is one in 1024, or approximately 0.1%. A setting of
all ones (1023) is 1023 in 1024, or approximately 99.9%.
There are a total of 16 probability entries. Each entry corresponds to a range
of the number of buffers used by the ingress port, as specified in Section
13.4.4.10, "Buffer Manager Random Discard Table Command Register
(BM_RNDM_DSCRD_TBL_CMD)".
RO 000h
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13.4.4.13 Buffer Manager Egress Port Type Register (BM_EGRSS_PORT_TYPE)
This register is used to configure the egress VLAN tagging rules. See Section 6.5.6, "Adding,
Removing, and Changing VLAN Tags," on page 92 for additional details.
Register #: 1C0Ch Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:23 RESERVED RO -
22 VID/Priority Select Port 2
This bit determines the VID and priority in inserted or changed tags.
0: The default VID of the ingress port / priority calculated on ingress.
1: The default VID / priority of the egress port.
This is only used when the Egress Port Type is set as Hybrid.
R/W 0b
21 Insert Tag Port 2
When set, untagged packets will have a tag added.The VID and priority is
determined by the VID/Priority Select Port 2 bit.
The un-tag bit in the VLAN table for the default VLAN ID also needs to be
cleared in order for the tag to be inserted.
This is only used when the Egress Port Type is set as Hybrid.
R/W 0b
20 Change VLAN ID Port 2
When set, regular tagged packets will have their VLAN ID overwritten with
the Default VLAN ID of either the ingress or egress port, as determined by
the VID/Priority Select Port 2 bit.
The Change Tag bit also needs to be set.
The un-tag bit in the VLAN table for the incoming VLAN ID also needs to be
cleared, otherwise the tag will be removed instead.
Priority tagged packets will have their VLAN ID overwritten with the Default
VLAN ID of either the ingress or egress port independent of this bit.
This is only used when the Egress Port Type is set as Hybrid.
R/W 0b
19 Change Priority Port 2
When set, regular tagged and priority tagged packets will have their Priority
overwritten with the priority determined by the VID/Priority Select Port 2 bit.
For regular tagged packets, the Change Tag bit also needs to be set.
The un-tag bit in the VLAN table for the incoming VLAN ID also needs to be
cleared, otherwise the tag would be removed instead.
This is only used when the Egress Port Type is set as Hybrid.
R/W 0b
18 Change Tag Port 2
When set, allows the Change Tag and Change Priority bits to affect regular
tagged packets.
This bit has no affect on priority tagged packets.
This is only used when the Egress Port Type is set as Hybrid.
R/W 0b
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17:16 Egress Port Type Port 2
These bits set the egress port type which determines the tagging/un-tagging
rules.
R/W 0b
15 RESERVED RO -
14 VID/Priority Select Port 1
Identical to VID/Priority Select Port 2 definition above.
R/W 0b
13 Insert Tag Port 1
Identical to Insert Tag Port 2 definition above.
R/W 0b
12 Change VLAN ID Port 1
Identical to Change VLAN ID Port 2 definition above.
R/W 0b
11 Change Priority Port 1
Identical to Change Priority Port 2 definition above.
R/W 0b
10 Change Tag Port 1
Identical to Change Tag Port 2 definition above.
R/W 0b
9:8 Egress Port Type Port 1
Identical to Egress Port Type Port 2 definition above.
R/W 0b
7RESERVED RO -
6VID/Priority Select Port 0
Identical to VID/Priority Select Port 2 definition above.
R/W 0b
5Insert Tag Port 0
Identical to Insert Tag Port 2 definition above.
R/W 0b
4Change VLAN ID Port 0
Identical to Change VLAN ID Port 2 definition above.
R/W 0b
3Change Priority Port 0
Identical to Change Priority Port 2 definition above.
R/W 0b
2Change Tag Port 0
Identical to Change Tag Port 2 definition above.
R/W 0b
1:0 Egress Port Type Port 0
Identical to Egress Port Type Port 2 definition above.
R/W 0b
BITS DESCRIPTION TYPE DEFAULT
BIT
VALUES EGRESS PORT TYPE
00 Dumb
Packets from regular ports pass untouched. Special tagged packets from the
External MII port have their tagged stripped.
01 Access
Tagged packets (including special tagged packets from the External MII port)
have their tagged stripped.
10 Hybrid
Supports a mix of tagging, un-tagging and changing tags. See Section 6.5.6,
"Adding, Removing, and Changing VLAN Tags," on page 92 for additional
details.
11 CPU
A special tag is added to indicate the source of the packet. See Section 6.5.6,
"Adding, Removing, and Changing VLAN Tags," on page 92 for additional
details.
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13.4.4.14 Buffer Manager Port 0 Egress Rate Priority Queue 0/1 Register (BM_EGRSS_RATE_00_01)
This register, along with the Buffer Manager Configuration Register (BM_CFG), is used to configure
the egress rate pacing.
Register #: 1C0Dh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:26 RESERVED RO -
25:13 Egress Rate Port 0 Priority Queue 1
These bits specify the egress data rate for the Port 0 priority queue 1. The
rate is specified in time per byte. The time is this value plus 1 times 20nS.
R/W 0000h
12:0 Egress Rate Port 0 Priority Queue 0
These bits specify the egress data rate for the Port 0 priority queue 0. The
rate is specified in time per byte. The time is this value plus 1 times 20nS.
R/W 0000h
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13.4.4.15 Buffer Manager Port 0 Egress Rate Priority Queue 2/3 Register (BM_EGRSS_RATE_02_03)
This register, along with the Buffer Manager Configuration Register (BM_CFG), is used to configure
the egress rate pacing.
Register #: 1C0Eh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:26 RESERVED RO -
25:13 Egress Rate Port 0 Priority Queue 3
These bits specify the egress data rate for the Port 0 priority queue 3. The
rate is specified in time per byte. The time is this value plus 1 times 20nS.
R/W 0000h
12:0 Egress Rate Port 0 Priority Queue 2
These bits specify the egress data rate for the Port 0 priority queue 2. The
rate is specified in time per byte. The time is this value plus 1 times 20nS.
R/W 0000h
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13.4.4.16 Buffer Manager Port 1 Egress Rate Priority Queue 0/1 Register (BM_EGRSS_RATE_10_11)
This register, along with the Buffer Manager Configuration Register (BM_CFG), is used to configure
the egress rate pacing.
Register #: 1C0Fh Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:26 RESERVED RO -
25:13 Egress Rate Port 1 Priority Queue 1
These bits specify the egress data rate for the Port 1 priority queue 1. The
rate is specified in time per byte. The time is this value plus 1 times 20nS.
R/W 0000h
12:0 Egress Rate Port 1 Priority Queue 0
These bits specify the egress data rate for the Port 1 priority queue 0. The
rate is specified in time per byte. The time is this value plus 1 times 20nS.
R/W 0000h
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13.4.4.17 Buffer Manager Port 1 Egress Rate Priority Queue 2/3 Register (BM_EGRSS_RATE_12_13)
This register, along with the Buffer Manager Configuration Register (BM_CFG), is used to configure
the egress rate pacing.
Register #: 1C10h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:26 RESERVED RO -
25:13 Egress Rate Port 1 Priority Queue 3
These bits specify the egress data rate for the Port 1 priority queue 3. The
rate is specified in time per byte. The time is this value plus 1 times 20nS.
R/W 0000h
12:0 Egress Rate Port 1 Priority Queue 2
These bits specify the egress data rate for the Port 1 priority queue 2. The
rate is specified in time per byte. The time is this value plus 1 times 20nS.
R/W 0000h
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13.4.4.18 Buffer Manager Port 2 Egress Rate Priority Queue 0/1 Register (BM_EGRSS_RATE_20_21)
This register, along with the Buffer Manager Configuration Register (BM_CFG), is used to configure
the egress rate pacing.
Register #: 1C11h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:26 RESERVED RO -
25:13 Egress Rate Port 2 Priority Queue 1
These bits specify the egress data rate for the Port 2 priority queue 1. The
rate is specified in time per byte. The time is this value plus 1 times 20nS.
R/W 0000h
12:0 Egress Rate Port 2 Priority Queue 0
These bits specify the egress data rate for the Port 2 priority queue 0. The
rate is specified in time per byte. The time is this value plus 1 times 20nS.
R/W 0000h
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13.4.4.19 Buffer Manager Port 2 Egress Rate Priority Queue 2/3 Register (BM_EGRSS_RATE_22_23)
This register, along with the Buffer Manager Configuration Register (BM_CFG), is used to configure
the egress rate pacing.
Register #: 1C12h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:26 RESERVED RO -
25:13 Egress Rate Port 2 Priority Queue 3
These bits specify the egress data rate for the Port 2 priority queue 3. The
rate is specified in time per byte. The time is this value plus 1 times 20nS.
R/W 0000h
12:0 Egress Rate Port 2 Priority Queue 2
These bits specify the egress data rate for the Port 2 priority queue 2. The
rate is specified in time per byte. The time is this value plus 1 times 20nS.
R/W 0000h
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13.4.4.20 Buffer Manager Port 0 Default VLAN ID and Priority Register (BM_VLAN_0)
This register is used to specify the default VLAN ID and priority of Port 0.
Register #: 1C13h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:15 RESERVED RO -
14:12 Default Priority
These bits specify the default priority that is used when a tag is inserted or
changed on egress.
R/W 000b
11:0 Default VLAN ID
These bits specify the default that is used when a tag is inserted or changed
on egress.
R/W 001h
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13.4.4.21 Buffer Manager Port 1 Default VLAN ID and Priority Register (BM_VLAN_1)
This register is used to specify the default VLAN ID and priority of Port 1.
Register #: 1C14h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:15 RESERVED RO -
14:12 Default Priority
These bits specify the default priority that is used when a tag is inserted or
changed on egress.
R/W 000b
11:0 Default VLAN ID
These bits specify the default that is used when a tag is inserted or changed
on egress.
R/W 001h
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13.4.4.22 Buffer Manager Port 2 Default VLAN ID and Priority Register (BM_VLAN_2)
This register is used to specify the default VLAN ID and priority of Port 2.
Register #: 1C15h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:15 RESERVED RO -
14:12 Default Priority
These bits specify the default priority that is used when a tag is inserted or
changed on egress.
R/W 000b
11:0 Default VLAN ID
These bits specify the default that is used when a tag is inserted or changed
on egress.
R/W 001h
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13.4.4.23 Buffer Manager Port 0 Ingress Rate Drop Count Register (BM_RATE_DRP_CNT_SRC_0)
This register counts the number of packets received on Port 0 that were dropped by the Buffer
Manager due to ingress rate limit discarding (Red and random Yellow dropping).
Register #: 1C16h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Dropped Count
These bits count the number of dropped packets received on Port 0 and is
cleared when read.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.4.24 Buffer Manager Port 1 Ingress Rate Drop Count Register (BM_RATE_DRP_CNT_SRC_1)
This register counts the number of packets received on Port 1 that were dropped by the Buffer
Manager due to ingress rate limit discarding (Red and random Yellow dropping).
Register #: 1C17h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Dropped Count
These bits count the number of dropped packets received on Port 1 and is
cleared when read.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.4.25 Buffer Manager Port 2 Ingress Rate Drop Count Register (BM_RATE_DRP_CNT_SRC_2)
This register counts the number of packets received on Port 2 that were dropped by the Buffer
Manager due to ingress rate limit discarding (Red and random Yellow dropping).
Register #: 1C18h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:0 Dropped Count
These bits count the number of dropped packets received on Port 2 and is
cleared when read.
Note: This counter will stop at its maximum value of FFFF_FFFFh.
Minimum rollover time at 100Mbps is approximately 481 hours.
RC 00000000h
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13.4.4.26 Buffer Manager Interrupt Mask Register (BM_IMR)
This register contains the Buffer Manager interrupt mask, which masks the interrupts in the Buffer
Manager Interrupt Pending Register (BM_IPR). All Buffer Manager interrupts are masked by setting
the Interrupt Mask bit. Clearing this bit will unmask the interrupts. Refer to Chapter 5, "System
Interrupts," on page 62 for more information.
Register #: 1C20h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:1 RESERVED RO -
0Interrupt Mask
When set, this bit masks interrupts from the Buffer Manager. The status bits
in the Buffer Manager Interrupt Pending Register (BM_IPR) are not affected.
R/W 1b
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13.4.4.27 Buffer Manager Interrupt Pending Register (BM_IPR)
This register contains the Buffer Manager interrupt status. The status is double buffered. All interrupts
in this register may be masked via the Buffer Manager Interrupt Mask Register (BM_IMR) register.
Refer to Chapter 5, "System Interrupts," on page 62 for more information.
Register #: 1C21h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:14 RESERVED RO -
13:10 Drop Reason B
When the Status B Pending bit is set, these bits indicate the reason a packet
was dropped per the table below:
RC 0h
9:8 Source Port B
When the Status B Pending bit is set, these bits indicate the source port on
which the packet was dropped.
00 = Port 0
01 = Port 1
10 = Port 2
11 = RESERVED
RC 00b
7Status B Pending
When set, bits 13:8 are valid.
RC 0b
BIT
VALUES DESCRIPTION
0000 The destination address was not in the ALR table (unknown or broadcast), and
the Broadcast Buffer Level was exceeded.
0001 Drop on Red was set and the packet was colored Red.
0010 There were no buffers available.
0011 There were no memory descriptors available.
0100 The destination address was not in the ALR table (unknown or broadcast) and
there were no valid destination ports.
0101 The packet had a receive error and was >64 bytes.
0110 The Buffer Drop Level was exceeded.
0111 RESERVED
1000 RESERVED
1001 Drop on Yellow was set, the packet was colored Yellow and was randomly
selected to be dropped.
1010 RESERVED
1011 RESERVED
1100 RESERVED
1101 RESERVED
1110 RESERVED
1111 RESERVED
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6:3 Drop Reason A
When the Set A Valid bit is set, these bits indicate the reason a packet was
dropped. See the Drop Reason B description above for definitions of each
value of this field.
RC 0h
2:1 Source port A
When the Set A Valid bit is set, these bits indicate the source port on which
the packet was dropped.
00 = Port 0
01 = Port 1
10 = Port 2
11 = RESERVED
RC 00b
0Set A Valid
When set, bits 6:1 are valid.
RC 0b
BITS DESCRIPTION TYPE DEFAULT
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Chapter 14 Operational Characteristics
14.1 Absolute Maximum Ratings*
Supply Voltage (VDD33A1, VDD33A2, VDD33BIAS, VDD33IO) (Note 14.1) . . . . . . . . . . . 0V to +3.6V
Positive voltage on signal pins, with respect to ground (Note 14.2) . . . . . . . . . . . . . . . . . . . . . . . . . +6V
Negative voltage on signal pins, with respect to ground (Note 14.3) . . . . . . . . . . . . . . . . . . . . . . . -0.5V
Positive voltage on XI, with respect to ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +4.6V
Positive voltage on XO, with respect to ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +2.5V
Ambient Operating Temperature in Still Air (TA). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Note 14.4
Storage Temperature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-55oC to +150oC
Lead Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Refer to JEDEC Spec. J-STD-020
HBM ESD Performance per JESD 22-A114-E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..+/- 8kV
Contact Discharge ESD Performance per IEC61000-4-2 (Note 14.5). . . . . . . . . . . . . . . . . . . . ..+/- 8kV
Air-Gap Discharge ESD Performance per IEC61000-4-2 (Note 14.5). . . . . . . . . . . . . . . . . . . ..+/- 15kV
Latch-up Performance per EIA/JESD 78 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .+/- 200mA
Note 14.1 When powering this device from laboratory or system power supplies, it is important that
the absolute maximum ratings not be exceeded or device failure can result. Some power
supplies exhibit voltage spikes on their outputs when AC power is switched on or off. In
addition, voltage transients on the AC power line may appear on the DC output. If this
possibility exists, it is suggested that a clamp circuit be used.
Note 14.2 This rating does not apply to the following pins: XI, XO, EXRES.
Note 14.3 This rating does not apply to the following pins: EXRES.
Note 14.4 0oC to +70oC for commercial version, -40oC to +85oC for industrial version.
Note 14.5 Performed by independant 3rd party test facility.
*Stresses exceeding those listed in this section could cause permanent damage to the device. This is
a stress rating only. Exposure to absolute maximum rating conditions for extended periods may affect
device reliability. Functional operation of the device at any condition exceeding those indicated in
Section 14.2, "Operating Conditions**", Section 14.4, "DC Specifications", or any other applicable
section of this specification is not implied. Note, device signals are NOT 5 volt tolerant.
14.2 Operating Conditions**
Supply Voltage (VDD33A1, VDD33A2, VDD33BIAS, VDD33IO). . . . . . . . . . . . . . . . . +3.3V +/- 300mV
Ambient Operating Temperature in Still Air (TA). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Note 14.4
**Proper operation of the device is guaranteed only within the ranges specified in this section.
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14.3 Power Consumption
This section details the device’s typical supply current for 10BASE-T, 100BASE-TX and power
management modes of operation.
Note: The typical supply current value was measured with 100% network loading.
Each port's transformer uses an additional 104ma @ 3.3V
Note: The typical supply current value was measured with 100% network loading.
Each port's transformer uses an additional 42ma @ 3.3V
Note: Power dissipation is determined by operating frequency, temperature, and supply voltage, as
well as external source/sink current requirements. All power dissipation values were measured
with both internal PHYs operating.
Table 14.1 Supply and Current (10BASE-T Full-Duplex)
PARAMETER TYPICAL UNIT
Supply current @ 3.3V
(VDD33A1, VDD33A2, VDD33BIAS, VDD33IO)
111 mA
Ambient Operating Temperature in Still Air (TA)24
oC
Table 14.2 Supply and Current (100BASE-TX Full-Duplex)
PARAMETER TYPICAL UNIT
Supply current @ 3.3V
(VDD33A1, VDD33A2, VDD33BIAS, VDD33IO)
190 mA
Ambient Operating Temperature in Still Air (TA)24
oC
Table 14.3 Supply and Current (Power Management)
PARAMETER TYPICAL UNIT
Both internal PHYs in Energy Detect Power Down @ 3.3V 74 mA
Both Internal PHYs in General Power Down @ 3.3V 44 mA
Ambient Operating Temperature in Still Air (TA)24
oC
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14.4 DC Specifications
Note 14.6 This specification applies to all IS type inputs and tri-stated bi-directional pins. Internal pull-
down and pull-up resistors add +/- 50uA per-pin (typical).
Note 14.7 XI can optionally be driven from a 25MHz single-ended clock oscillator.
Table 14.4 I/O Buffer Characteristics
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
IS Type Input Buffer
Low Input Level
High Input Level
Negative-Going Threshold
Positive-Going Threshold
SchmittTrigger Hysteresis
(VIHT - VILT)
Input Leakage
Input Capacitance
VILI
VIHI
VILT
VIHT
VHYS
IIN
CIN
-0.3
1.01
1.39
345
-10
1.18
1.6
420
3.6
1.35
1.8
485
10
3
V
V
V
V
mV
uA
pF
Schmitt trigger
Schmitt trigger
Note 14.6
O8 Type Buffers
Low Output Level
High Output Level
VOL
VOH VDD33IO - 0.4
0.4 V
V
IOL = 8mA
IOH = -8mA
OD8 Type Buffer
Low Output Level VOL 0.4 V IOL = 8mA
O12 Type Buffer
Low Output Level
High Output Level
VOL
VOH VDD33IO - 0.4
0.4 V
V
IOL = 12mA
IOH = -12mA
OD12 Type Buffer
Low Output Level VOL 0.4 V IOL = 12mA
OS12
High Output Level VOH VDD33IO - 0.4 VI
OH = -12mA
O16 Type Buffer
Low Output Level
High Output Level
VOL
VOH VDD33IO - 0.6
0.4 V
V
IOL = 16mA
IOH = -16mA
ICLK Type Buffer (XI Input)
Low Input Level
High Input Level
VILI
VIHI
-0.3
1.4
0.5
3.6
V
V
Note 14.7
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Note 14.8 Measured at line side of transformer, line replaced by 100Ω (+/- 1%) resistor.
Note 14.9 Offset from 16nS pulse width at 50% of pulse peak.
Note 14.10 Measured differentially.
Note 14.11 Min/max voltages guaranteed as measured with 100Ω resistive load.
Table 14.5 100BASE-TX Transceiver Characteristics
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Peak Differential Output Voltage High VPPH 950 - 1050 mVpk Note 14.8
Peak Differential Output Voltage Low VPPL -950 - -1050 mVpk Note 14.8
Signal Amplitude Symmetry VSS 98 - 102 % Note 14.8
Signal Rise and Fall Time TRF 3.0 - 5.0 nS Note 14.8
Rise and Fall Symmetry TRFS --0.5nSNote 14.8
Duty Cycle Distortion DCD 35 50 65 % Note 14.9
Overshoot and Undershoot VOS --5%
Jitter 1.4 nS Note 14.10
Table 14.6 10BASE-T Transceiver Characteristics
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Transmitter Peak Differential Output Voltage VOUT 2.2 2.5 2.8 V Note 14.11
Receiver Differential Squelch Threshold VDS 300 420 585 mV
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14.5 AC Specifications
This section details the various AC timing specifications of the device.
Note: The I2C timing adheres to the NXP I2C-Bus Specification. Refer to the NXP I2C-Bus
Specification for detailed I2C timing information.
Note: The MII/SMI timing adheres to the IEEE 802.3 specification.
Note: The RMII timing adheres to the RMII Consortium RMII Specification R1.2.
14.5.1 Equivalent Test Load
Output timing specifications assume the 25pF equivalent test load, unless otherwise noted, as
illustrated in Figure 14.1 below.
Figure 14.1 Output Equivalent Test Load
25 pF
OUTPUT
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14.5.2 Reset and Configuration Strap Timing
This diagram illustrates the nRST pin timing requirements and its relation to the configuration strap
pins and output drive. Assertion of nRST is not a requirement. However, if used, it must be asserted
for the minimum period specified. Please refer to Section 4.2, "Resets," on page 48 for additional
information.
Note: Device configuration straps are latched as a result of nRST assertion. Refer to Section 4.2.4,
"Configuration Straps," on page 52 for details.
Figure 14.2 nRST Reset Pin Timing
Table 14.7 nRST Reset Pin Timing Values
SYMBOL DESCRIPTION MIN TYP MAX UNITS
trstia nRST input assertion time 200 μS
tcss Configuration strap pins setup to nRST deassertion 200 nS
tcsh Configuration strap pins hold after nRST deassertion 10 nS
todad Output drive after deassertion 30 nS
tcss
nRST
Configuration
Strap Pins
trstia
tcsh
Output Drive
todad
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14.5.3 Power-On Configuration Strap Valid Timing
This diagram illustrates the configuration strap valid timing requirements in relation to power-on. In
order for valid configuration strap values to be read at power-on, the following timing requirements
must be met.
Note: Configuration straps must only be pulled high or low. Configuration straps must not be driven
as inputs.
Note: Device configuration straps are also latched as a result of nRST assertion. Refer to Section
14.5.2, "Reset and Configuration Strap Timing," on page 368 and Section 4.2.4, "Configuration
Straps," on page 52 for additional details.
Figure 14.3 Power-On Configuration Strap Latching Timing
Table 14.8 Power-On Configuration Strap Latching Timing Values
SYMBOL DESCRIPTION MIN TYP MAX UNITS
tcfg Configuration strap valid time 15 mS
VDD33IO
Configuration Straps
tcfg
2.0V
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14.5.4 MII Interface Timing (MAC Mode)
This section specifies the MII interface input and output timing when in MAC mode. Please refer to
Chapter 9, "MII Data Interfaces," on page 129 for additional details.
Note 14.12 Timing was designed for system load between 10pf and 25 pf.
Figure 14.4 MII Output Timing (MAC Mode)
Table 14.9 MII Output Timing Values (MAC Mode)
SYMBOL DESCRIPTION MIN MAX UNITS NOTES
tclkp Px_OUTCLK period 40 ns
tclkh Px_OUTCLK high time tclkp*0.4 tclkp*0.6 ns
tclkl Px_OUTCLK low time tclkp*0.4 tclkp*0.6 ns
tval Px_OUTD[3:0], Px_OUTDV output valid from
rising edge of Px_OUTCLK
22.0 ns Note 14.12
thold Px_OUTD[3:0], Px_OUTDV output hold from
rising edge of Px_OUTCLK
0nsNote 14.12
Px_OUTCLK
Px_OUTD[3:0]
Px_OUTDV
tclkh tclkl
tclkp
tval thold
(input) tval
tval
thold
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Note 14.13 Timing was designed for system load between 10pf and 25 pf.
Figure 14.5 MII Input Timing (MAC Mode)
Table 14.10 MII Input Timing Values (MAC Mode)
SYMBOL DESCRIPTION MIN MAX UNITS NOTES
tclkp Px_INCLK period 40 ns
tclkh Px_INCLK high time tclkp*0.4 tclkp*0.6 ns
tclkl Px_INCLK low time tclkp*0.4 tclkp*0.6 ns
tsu Px_IND[3:0], Px_INDV setup time to rising edge
of Px_INCLK
8.0 ns Note 14.13
thold Px_IND[3:0], Px_INDV hold time after rising
edge of Px_INCLK
9.0 ns Note 14.13
Px_INCLK
tsu
Px_IND[3:0]
Px_INDV
tclkh tclkl
tclkp
thold tsu thold thold
tsu
(input)
thold
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14.5.5 MII Interface Timing (PHY Mode)
This section specifies the MII interface input and output timing when in PHY mode. Please refer to
Chapter 9, "MII Data Interfaces," on page 129 for additional details.
Note 14.14 Timing was designed for system load between 10 pf and 25 pf.
Figure 14.6 MII Output Timing (PHY Mode)
Table 14.11 MII Output Timing Values (PHY Mode)
SYMBOL DESCRIPTION MIN MAX UNITS NOTES
tclkp Px_OUTCLK period 40 ns
tclkh Px_OUTCLK high time tclkp*0.4 tclkp*0.6 ns
tclkl Px_OUTCLK low time tclkp*0.4 tclkp*0.6 ns
tval Px_OUTD[3:0], Px_OUTDV output valid from
rising edge of Px_OUTCLK
28.0 ns Note 14.14
thold Px_OUTD[3:0], Px_OUTDV output hold from
rising edge of Px_OUTCLK
10.0 ns Note 14.14
Px_OUTCLK
Px_OUTD[3:0]
Px_OUTDV
tclkh tclkl
tclkp
tval thold
(output) tval
tval
thold
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Note 14.15 Timing was designed for system load between 10 pf and 25 pf.
Figure 14.7 MII Input Timing (PHY Mode)
Table 14.12 MII Input Timing Values (PHY Mode)
SYMBOL DESCRIPTION MIN MAX UNITS NOTES
tclkp Px_INCLK period 40 ns
tclkh Px_INCLK high time tclkp*0.4 tclkp*0.6 ns
tclkl Px_INCLK low time tclkp*0.4 tclkp*0.6 ns
tsu Px_IND[3:0], Px_INDV setup time to rising edge
of Px_INCLK
9.0 ns Note 14.15
thold Px_IND[3:0], Px_INDV hold time after rising
edge of Px_INCLK
0nsNote 14.15
Px_INCLK
tsu
Px_IND[3:0]
Px_INDV
tclkh tclkl
tclkp
thold tsu thold thold
tsu
(output)
thold
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14.5.6 Turbo MII Interface Timing (MAC Mode)
This section specifies the Turbo MII interface input and output timing when in MAC mode. Please refer
to Chapter 9, "MII Data Interfaces," on page 129 for additional details.
Note 14.16 Timing was designed for system load between 10pf and 15 pf.
Figure 14.8 Turbo MII Output Timing (MAC Mode)
Table 14.13 Turbo MII Output Timing Values (MAC Mode)
SYMBOL DESCRIPTION MIN MAX UNITS NOTES
tclkp Px_OUTCLK period 20 ns
tclkh Px_OUTCLK high time tclkp*0.4 tclkp*0.6 ns
tclkl Px_OUTCLK low time tclkp*0.4 tclkp*0.6 ns
tval Px_OUTD[3:0], Px_OUTDV output valid from
rising edge of Px_OUTCLK
11.0 ns Note 14.16
thold Px_OUTD[3:0], Px_OUTDV output hold from
rising edge of Px_OUTCLK
2.0 ns Note 14.16
Px_OUTCLK
Px_OUTD[3:0]
Px_OUTDV
tclkh tclkl
tclkp
tval thold
(input) tval
tval
thold
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Note 14.17 Timing was designed for system load between 10pf and 15 pf.
Figure 14.9 Turbo MII Input Timing (MAC Mode)
Table 14.14 Turbo MII Input Timing Values (MAC Mode)
SYMBOL DESCRIPTION MIN MAX UNITS NOTES
tclkp Px_INCLK period 20 ns
tclkh Px_INCLK high time tclkp*0.4 tclkp*0.6 ns
tclkl Px_INCLK low time tclkp*0.4 tclkp*0.6 ns
tsu Px_IND[3:0], Px_INDV setup time to rising edge
of Px_INCLK
4.0 ns Note 14.17
thold Px_IND[3:0], Px_INDV hold time after rising
edge of Px_INCLK
0nsNote 14.17
Px_INCLK
tsu
Px_IND[3:0]
Px_INDV
tclkh tclkl
tclkp
thold tsu thold thold
tsu
(input)
thold
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14.5.7 Turbo MII Interface Timing (PHY Mode)
This section specifies the Turbo MII interface input and output timing when in PHY mode. Please refer
to Chapter 9, "MII Data Interfaces," on page 129 for additional details.
Note 14.18 Timing was designed for system load between 10 pf and 15 pf.
Figure 14.10 Turbo MII Output Timing (PHY Mode)
Table 14.15 Turbo MII Output Timing Values (PHY Mode)
SYMBOL DESCRIPTION MIN MAX UNITS NOTES
tclkp Px_OUTCLK period 20 ns
tclkh Px_OUTCLK high time tclkp*0.4 tclkp*0.6 ns
tclkl Px_OUTCLK low time tclkp*0.4 tclkp*0.6 ns
tval Px_OUTD[3:0], Px_OUTDV output valid from
rising edge of Px_OUTCLK
14.0 ns Note 14.18
thold Px_OUTD[3:0], Px_OUTDV output hold from
rising edge of Px_OUTCLK
2.0 ns Note 14.18
Px_OUTCLK
Px_OUTD[3:0]
Px_OUTDV
tclkh tclkl
tclkp
tval thold
(output) tval
tval
thold
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Note 14.19 Timing was designed for system load between 10 pf and 15 pf.
Figure 14.11 Turbo MII Input Timing (PHY Mode)
Table 14.16 Turbo MII Input Timing Values (PHY Mode)
SYMBOL DESCRIPTION MIN MAX UNITS NOTES
tclkp Px_INCLK period 20 ns
tclkh Px_INCLK high time tclkp*0.4 tclkp*0.6 ns
tclkl Px_INCLK low time tclkp*0.4 tclkp*0.6 ns
tsu Px_IND[3:0], Px_INDV setup time to rising edge
of Px_INCLK
7.0 ns Note 14.19
thold Px_IND[3:0], Px_INDV hold time after rising
edge of Px_INCLK
0nsNote 14.19
Px_INCLK
tsu
Px_IND[3:0]
Px_INDV
tclkh tclkl
tclkp
thold tsu thold thold
tsu
(output)
thold
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14.5.8 RMII Interface Timing
This section specifies the RMII interface timing for Px_OUTCLK input and output modes. Please refer
to Chapter 9, "MII Data Interfaces," on page 129 for additional details.
Figure 14.12 RMII Px_OUTCLK Output Mode Timing
Table 14.17 RMII Px_OUTCLK Output Mode Timing Values
SYMBOL DESCRIPTION MIN MAX UNITS NOTES
tclkp Px_OUTCLK period 20 ns
tclkh Px_OUTCLK high time tclkp*0.4 tclkp*0.6 ns
tclkl Px_OUTCLK low time tclkp*0.4 tclkp*0.6 ns
tval Px_OUTD[1:0], Px_OUTDV output valid from
rising edge of Px_OUTCLK
14.0 ns Note 14.20
tohold Px_OUTD[1:0], Px_OUTDV output hold from
rising edge of Px_OUTCLK
2.0 ns Note 14.20
tsu Px_IND[1:0], Px_INDV setup time to rising edge
of Px_INCLK
4.0 ns Note 14.20
tihold Px_IND[1:0], Px_INDV input hold time after
rising edge of Px_INCLK
1.5 ns Note 14.20
Px_OUTCLK
Px_OUTD[1:0]
Px_OUTDV
tclkh tclkl
tclkp
tval tohold
(output) tval
tval
tohold
tsu
Px_IND[1:0]
Px_INDV
tihold tsu tihold tihold
tsu
tihold
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Note 14.20 Timing was designed for system load between 10 pf and 25 pf.
Note 14.21 Timing was designed for system load between 10 pf and 25 pf.
Figure 14.13 RMII Px_OUTCLK Input Mode Timing
Table 14.18 RMII Px_OUTCLK Input Mode Timing Values
SYMBOL DESCRIPTION MIN MAX UNITS NOTES
tclkp Px_OUTCLK period 20 ns
tclkh Px_OUTCLK high time tclkp*0.35 tclkp*0.65 ns
tclkl Px_OUTCLK low time tclkp*0.35 tclkp*0.65 ns
toval Px_OUTD[1:0], Px_OUTDV output valid from
rising edge of Px_OUTCLK
14.0 ns Note 14.21
tohold Px_OUTD[1:0], Px_OUTDV output hold from
rising edge of Px_OUTCLK
3.0 ns Note 14.21
tsu Px_IND[1:0], Px_INDV setup time to rising edge
of Px_INCLK
4.0 ns Note 14.21
tihold Px_IND[1:0], Px_INDV input hold time after
rising edge of Px_INCLK
1.5 ns Note 14.21
Px_OUTCLK
Px_OUTD[1:0]
Px_OUTDV
tclkh tclkl
tclkp
tval tohold
(input) tval
tval
tohold
tsu
Px_IND[1:0]
Px_INDV
tihold tsu tihold tihold
tsu
tihold
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14.5.9 SMI Timing
This section specifies the SMI timing of the device in both master and slave modes. Please refer to
Chapter 9, "MII Data Interfaces," on page 129 for additional details.
Figure 14.14 SMI Timing
Table 14.19 SMI Timing Values
SYMBOL DESCRIPTION MIN MAX UNITS NOTES
tclkp MDC period 400 ns
tclkh
MDC high time (slave mode - clock is input) 160 (80%) ns
MDC high time (master mode - clock is output) 180 (90%) ns
tclkl
MDC low time (slave mode - clock is input) 160 (80%) ns
MDC low time (master mode - clock is output) 180 (90%) ns
tval
MDIO (slave mode - read from PHY) output
valid from rising edge of MDC
300 ns
MDIO (master mode - write to PHY) output valid
from rising edge of MDC
250 ns
tohold
MDIO (slave mode - read from PHY) output hold
from rising edge of MDC
10 ns
MDIO (master mode - write to PHY) output hold
from rising edge of MDC
50 ns
tsu
MDIO (slave mode - write to PHY) setup time to
rising edge of MDC
10 ns
MDIO (master mode - read from PHY) setup
time to rising edge of MDC
70 ns
MDC
MDIO
tclkh tclkl
tclkp
tohold
MDIO
tsu tihold
(Data-Out)
(Data-In)
tohold
tval
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tihold
MDIO (slave mode - write to PHY) input hold
time after rising edge of MDC
5ns
MDIO (master mode - read from PHY) input
hold time after rising edge of MDC
0ns
Table 14.19 SMI Timing Values
SYMBOL DESCRIPTION MIN MAX UNITS NOTES
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14.6 Clock Circuit
The device can accept either a 25MHz crystal (preferred) or a 25MHz single-ended clock oscillator (+/-
50ppm) input. If the single-ended clock oscillator method is implemented, XO should be left
unconnected and XI should be driven with a nominal 0-3.3V clock signal. The input clock duty cycle
is 40% minimum, 50% typical and 60% maximum.
It is recommended that a crystal utilizing matching parallel load capacitors be used for the crystal
input/output signals (XI/XO). See Table 14.20 for crystal specifications.
Note 14.22 The maximum allowable values for Frequency Tolerance and Frequency Stability are
application dependant. Since any particular application must meet the IEEE +/-50 PPM
Total PPM Budget, the combination of these two values must be approximately +/-45 PPM
(allowing for aging).
Note 14.23 Frequency Deviation Over Time is also referred to as Aging.
Note 14.24 The total deviation for the Transmitter Clock Frequency is specified by IEEE 802.3 as
+/- 50 PPM.
Note 14.25 0oC for commercial version, -40oC for industrial version.
Note 14.26 +70oC for commercial version, +85oC for industrial version.
Note 14.27 This number includes the pad, the bond wire and the lead frame. PCB capacitance is not
included in this value. The XO/XI pin and PCB capacitance values are required to
accurately calculate the value of the two external load capacitors. These two external load
capacitors determine the accuracy of the 25.000 MHz frequency.
Table 14.20 Crystal Specifications
PARAMETER SYMBOL MIN NOM MAX UNITS NOTES
Crystal Cut AT, typ
Crystal Oscillation Mode Fundamental Mode
Crystal Calibration Mode Parallel Resonant Mode
Frequency Ffund - 25.000 - MHz
Frequency Tolerance @ 25oCF
tol --+/-50PPMNote 14.22
Frequency Stability Over Temp Ftemp --+/-50PPMNote 14.22
Frequency Deviation Over Time Fage - +/-3 to 5 - PPM Note 14.23
Total Allowable PPM Budget - - +/-50 PPM Note 14.24
Shunt Capacitance CO-7 typ-pF
Load Capacitance CL- 20 typ - pF
Drive Level PW300 - - uW
Equivalent Series Resistance R1--30Ohm
Operating Temperature Range Note 14.25 -Note 14.26 oC
XI Pin Capacitance - 3 typ - pF Note 14.27
XO Pin Capacitance - 3 typ - pF Note 14.27
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 383 Revision 1.5 (07-08-11)
DATASHEET
Chapter 15 Package Outline
15.1 72-QFN Package Outline
Notes:
1. All dimensions are in millimeters unless otherwise noted.
2. Dimension “b” applies to plated terminals and is measured between 0.15 and 0.30mm from the terminal tip.
3. The pin 1 identifier may vary, but is always located within the zone indicated
Figure 15.1 72-QFN Package Definition
Table 15.1 72-QFN Dimensions
MIN NOMINAL MAX REMARKS
A 0.80 0.85 1.00 Overall Package Height
A1 0 0.02 0.05 Standoff
A2 - 0.65 0.80 Mold Cap Thickness
D/E 9.90 10.00 10.10 X/Y Body Size
D1/E1 9.65 9.75 9.85 X/Y Mold Cap Size
D2/E2 5.90 6.00 6.10 X/Y Exposed Pad Size
L 0.30 0.40 0.50 Terminal Length
b 0.18 0.25 0.30 Terminal Width
e 0.50 BSC Terminal Pitch
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 384 SMSC LAN9303M/LAN9303Mi
DATASHEET
.
Figure 15.2 72-QFN Recommended PCB Land Pattern
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
SMSC LAN9303M/LAN9303Mi 385 Revision 1.5 (07-08-11)
DATASHEET
Chapter 16 Datasheet Revision History
Table 16.1 Customer Revision History
REVISION LEVEL & DATE SECTION/FIGURE/ENTRY CORRECTION
Rev. 1.5 (07-08-11) Table 14.19, “SMI Timing
Values,” on page 380
Changed tval to 300 from 200 for slave mode.
Table 4.3, “Hard-Strap
Configuration Strap
Definitions,” on page 59
Added notes to the P0_rmii_clock_dir_strap and
P1_rmii_clock_dir_strap: “The value of this strap is
the inverse of the Px_MODE1 pin.” (where x is the
appropriate port)
Rev. 1.4 (07-07-10) Table 3.7, “Serial
Management/EEPROM
Pins,” on page 44
Added note to EE_SDA/SDA and EE_SCL/SCL
pin descriptions stating “This pin must be pulled-up
by an external resistor at all times.”
Section 13.4.2.23, "Port x
MAC Transmit Configuration
Register
(MAC_TX_CFG_x)," on
page 265
Added note to IFG Config bit: “IFG Config values
less than 15 are unsupported.”
Section 13.4.3.10, "Switch
Engine VLAN Read Data
Register
(SWE_VLAN_RD_DATA),"
on page 299
Updated field descriptions for Port Default VID and
Prioroty, bits 16 and 11:0 to match those of the
SWE_VLAN_WR_DATA register.
Table 7.2, “4B/5B Code
Table,” on page 99
Corrected typo in 10001 code group receiver
interpretation. “J” changed to “/J/”.
Section 1.1, "General
Terms," on page 13
Added 10BASE-T and 100BASE-TX definitions to
general terms list, replacing “100BT”.
Table 6.1, “Switch Fabric
Flow Control Enable Logic,”
on page 71
Corrected typo in last column title. “RX FLOW
CONTROL ENABLE” changed to “TX FLOW
CONTROL ENABLE”
Section 13.2.6.4, "Virtual
PHY Identification LSB
Register (VPHY_ID_LSB),"
on page 187, Section
13.3.2.4, "Port x PHY
Identification LSB Register
(PHY_ID_LSB_x)," on
page 213
Clarified default values using binary.
Figure 14.2 nRST Reset Pin
Timing on page 368
Updated diagram with correct shading.
Rev. 1.3 (08-27-09) Section 14.5, "AC
Specifications," on page 367
Added MII, RMII, and SMI timing diagrams and
specifications.
Section 14.1, "Absolute
Maximum Ratings*," on
page 363 and Cover
Added ESD rating information
Section 14.3, "Power
Consumption," on page 364
Added power consumption information
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII
Datasheet
Revision 1.5 (07-08-11) 386 SMSC LAN9303M/LAN9303Mi
DATASHEET
All Updated part number information throughout
document: “LAN9303DM/LAN9303DMi” changed
to “LAN9303M/LAN9303iM”
Rev. 1.2 (12-19-08) Initial Release
Table 16.1 Customer Revision History (continued)
REVISION LEVEL & DATE SECTION/FIGURE/ENTRY CORRECTION
Mouser Electronics
Authorized Distributor
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