LAN9303M-AKZE - Standard Microsystems

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

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

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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

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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

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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

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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

Access

MUX

SMI (slave)

Controller

System

Registers

(CSRs)

MII

Mode

MUX

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

Engine

Frame

Buffers

MII

MDIO

Mode Configuration

Straps

MDIO

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

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

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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.

Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII

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DATASHEET

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.

Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII

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DATASHEET

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.

Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII

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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

Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII

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SMSC LAN9303M/LAN9303Mi 21 Revision 1.5 (07-08-11)

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

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

Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII

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Revision 1.5 (07-08-11) 22 SMSC LAN9303M/LAN9303Mi

DATASHEET

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

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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DATASHEET

Chapter 3 Pin Description and Configuration

3.1 Pin Diagram

3.1.1 72-QFN Pin Diagram

Figure 3.1 Pin Assignments (TOP VIEW)

VSS

NOTE: Exposed pad (VSS) on bottom of package must be connected to ground

NOTE: When HP Auto-MDIX is activated, the TXN/TXP pins can function as RXN/RXP and vice-versa

SMSC

LAN9303M/LAN9303Mi

72 PIN QFN

(TOP VIEW)

TXP1

IRQ

LED0/GPIO0/AMDIX1_LED0P

P1_IND0

P1_IND1

P1_IND2

P1_IND3

P0_OUTD0/P0_MODE0

P0_OUTD1/P0_MODE1

P0_OUTD2/P0_MODE2

P0_OUTD3/DUPLEX_POL_0

VDD18CORE

VDD33IO

P0_INCLK

P0_INER

P0_INDV

P0_IND0

nRST

EE_SCL/SCL

EE_SDA/SDA

TEST2

TEST1

VDD33IO

P1_OUTD0/P1_MODE0

P1_OUTD1/P1_MODE1

P1_OUTCLK

P1_OUTDV

VDD18CORE

VDD33IO

P1_OUTD2/P1_MODE2

VDD33A1

RXN1

RXP1

VDD33A1

VDD18TX1

EXRES

VDD33BIAS

VDD18TX2

VDD33A2

RXP2

RXN2

VDD33A2

LED1/GPIO1/AMDIX2_LED1P

LED2/GPIO2/E2PSIZE_LED2P

LED3/GPIO3/MNGT0_LED3P

LED4/GPIO4/MNGT1_LED4P

LED5/GPIO5/PHYADDR_LED5P

VDD33IO

MDC

MDIO

P0_DUPLEX

P0_CRS

P0_COL

P0_OUTCLK

P0_OUTDV

VDD18PLL

TXN1

TXP2

TXN2

P0_IND3

P1_OUTD3/DUPLEX_POL_1

P1_CRS

P0_IND1

P0_IND2

P1_INDV

VDD33IO

20 P1_INCLK

P1_INER

36 P1_COL

P1_DUPLEX

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Revision 1.5 (07-08-11) 24 SMSC LAN9303M/LAN9303Mi

DATASHEET

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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DATASHEET

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.

+3.3V Port 1

Analog Power

Supply

VDD33A1 P See Note 3.3.

+3.3V Port 2

Analog Power

Supply

VDD33A2 P See Note 3.3.

+3.3V Master

Bias Power

Supply

VDD33BIAS P See Note 3.3.

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.

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

Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII

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Revision 1.5 (07-08-11) 26 SMSC LAN9303M/LAN9303Mi

DATASHEET

Table 3.4 Port 1 MII/RMII Pins

NUM

PINS NAME SYMBOL

BUFFER

TYPE DESCRIPTION

1Port 1 MII Input

Data 3 P1_IND3

(PD)

MII MAC Mode: This pin is the receive data 3 bit

from the external PHY to the switch.

(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

(PD)

MII MAC Mode: This pin is the receive data 2 bit

from the external PHY to the switch.

(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

(PD)

MII MAC Mode: This pin is the receive data 1 bit

from the external PHY to the switch.

(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).

(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

(PD)

MII MAC Mode: This pin is the receive data 0 bit

from the external PHY to the switch.

(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).

(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.

Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII

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DATASHEET

1Port 1 MII Input

Data Valid P1_INDV

(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.

(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).

(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

(PD)

MII MAC Mode: This pin is the RX_ER signal from

the external PHY and indicates a receive error in

the packet.

(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.

Port 1 MII Input

Reference

Clock

P1_INCLK

(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

Datasheet

Revision 1.5 (07-08-11) 28 SMSC LAN9303M/LAN9303Mi

DATASHEET

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.

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.

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

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

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

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

Port 1 MII

Output

Reference

Clock

P1_OUTCLK

(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

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

(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

(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

(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.

(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

(PD)

MII MAC Mode: This pin is the receive data 3 bit

from the external PHY to the switch.

(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

(PD)

MII MAC Mode: This pin is the receive data 2 bit

from the external PHY to the switch.

(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

(PD)

MII MAC Mode: This pin is the receive data 1 bit

from the external PHY to the switch.

(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).

(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

(PD)

MII MAC Mode: This pin is the receive data 0 bit

from the external PHY to the switch.

(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).

(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

(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.

(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).

(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

(PD)

MII MAC Mode: This pin is the RX_ER signal from

the external PHY and indicates a receive error in

the packet.

(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.

Port 0 MII Input

Reference

Clock

P0_INCLK

(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.

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

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.

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

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

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

Port 0 MII

Output

Reference

Clock

P0_OUTCLK

(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

(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

(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

(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.

(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.

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.

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

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

depends on the setting of the LED Function 1-0

(LED_FUN[1:0]) field in the LED Configuration

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

programmable as either a push-pull output, an

open-drain output, or a Schmitt-triggered input by

writing the General Purpose I/O Configuration

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.

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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

depends on the setting of the LED Function 1-0

(LED_FUN[1:0]) field in the LED Configuration

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

programmable as either a push-pull output, an

open-drain output, or a Schmitt-triggered input by

writing the General Purpose I/O Configuration

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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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

depends on the setting of the LED Function 1-0

(LED_FUN[1:0]) field in the LED Configuration

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

programmable as either a push-pull output, an

open-drain output, or a Schmitt-triggered input by

writing the General Purpose I/O Configuration

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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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

depends on the setting of the LED Function 1-0

(LED_FUN[1:0]) field in the LED Configuration

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

programmable as either a push-pull output, an

open-drain output, or a Schmitt-triggered input by

writing the General Purpose I/O Configuration

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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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

depends on the setting of the LED Function 1-0

(LED_FUN[1:0]) field in the LED Configuration

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

programmable as either a push-pull output, an

open-drain output, or a Schmitt-triggered input by

writing the General Purpose I/O Configuration

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.

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

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

programmable as either a push-pull output, an

open-drain output, or a Schmitt-triggered input by

writing the General Purpose I/O Configuration

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

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.

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

Interrupt Output IRQ O8/OD8 The polarity, source and buffer type of this signal is

programmable via the Interrupt Configuration

"System Interrupts," on page 62 for further details.

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.

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

PLL +1.8V

Power Supply

VDD18PLL P This pin must be connected to VDD18CORE for

proper operation.

See Note 3.9.

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

+3.3V I/O

Power

VDD33IO P +3.3V Power Supply for I/O Pins and Internal

Regulator.

See Note 3.10.

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.

PAD

Common

Ground

VSS P Ground

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Table 3.11 LAN9303M/LAN9303Mi 72-QFN Package Pin Assignments

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

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

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

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

(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

(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).

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

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.

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

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

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.

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).

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

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

This strap may affect the default value of the following

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.

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.

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.

Table 4.2 Soft-Strap Configuration Strap Definitions (continued)

STRAP NAME DESCRIPTION PIN / DEFAULT

VALUE

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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

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.

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

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.

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.

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).

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

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

This strap may affect the default value of the following

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.

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).

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

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.

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

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)

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

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.

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.

Table 4.2 Soft-Strap Configuration Strap Definitions (continued)

STRAP NAME DESCRIPTION PIN / DEFAULT

VALUE

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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

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

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

Interrupt Mask Register (SWE_IMR) for the Switch Engine, and/or Port x MAC Interrupt Mask

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

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

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

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

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

Write

Command

Read

Command

CSR_BUSY = 0

CSR Write

CSR_BUSY = 1

Idle

Write Data

Write

Command

Read

Command

CSR_BUSY = 0

CSR Write Auto

Increment /

Decrement

CSR_BUSY = 1

Idle

Write

Direct

Data

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

Read

Command

Read Data

CSR_BUSY = 0

CSR Read

CSR_BUSY = 1

Idle

Write

Command

Read

Command

CSR_BUSY = 0

CSR Read Auto

Increment /

Decrement

CSR_BUSY = 1

Write

Command

Read Data

last

data?

Yes

No Read Data

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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

(Note 6.2)

AN ASYM PAUSE

(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

Age /

Override

Valid

Static

Filter

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

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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

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

6b 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

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

Resolved Priority =

Priority Regen[VLAN

Priority]

Packet is IPv4/v6

& Use IP

Resolved Priority =

IP Precedence

Use Precedence

Y N

Resolved Priority =

DIFFSERV[TC]

Use Tag &

Packet is

Tagged

Resolved Priority =

Default Priority[Source

Port]

wait for ALR result

Queue =

Traffic Class[Resolved Priority]

Packet is IPv4

Resolved Priority =

DIFFSERV[TOS]

Get Queue Done

VL Higher

Priority

Use Tag &

Packet is

Tagged

Get Queue

Packet fr om Host

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

(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

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

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

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

Flow Priority =

Priority Regen[VLAN

Priority]

Packet is IPv4/v6

& Use IP

Flow Priority =

IP Precedence

Use Precedence

Y N

Flow Priority =

DIFFSERV[TC]

Use Tag &

Packet is

Tagged

Flow Priority =

Default Priority[Source

Port]

wait for ALR result

Packet is IPv4

Flow Priority =

DIFFSERV[TOS]

Get Flow Priority Done

VL Higher

Priority

Use Tag &

Packet is

Tagged

Get Flow Priority

Packet

from Host & queue

calc ulation not

requested

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

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

Non-tagged

Add Tag

VID = Default VID

[ingress_port or egress port*]

Priority = ingress priority or

Default Priority

[egress_port]*

Send Packet Untouched

Priority Tagged

Default VID

[ingress_port]

Un-tag Bit

Strip Tag

Normal Tagged

Received VID

Un-tag Bit

Strip Tag

Change Tag

[egress_port]

Send Packet Untouched

Change Priority

[egress_port]

Modify Tag

VID = Default VID

[ingress_port or egress port*]

Priority = ingress priority or

Default Priority [egress_port]*

Change VLAN ID

[egress_port]

Change Priority

[egress_port]

Change Priority

[egress_port]

Y N

Modify Tag

VID = Default VID [ingress

port or egress_port*]

Priority = ingress priority or

Default Priority

[egress_port]*

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

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

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

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

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

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

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

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

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

TXPx

TXNx

RXPx

Not Used

RXNx

Not Used

TXPx

TXNx

RXPx

Not Used

RXNx

Not Used

Direct Connect Cable

RJ-45 8-pin straight-through

for 10BASE-T/100BASE-TX

signaling

TXPx

TXNx

RXPx

Not Used

RXNx

Not Used

TXPx

TXNx

RXPx

Not Used

RXNx

Not Used

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

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

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

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

Start Condition

Stop Condition

Data Valid

or Ack

Data Valid

or Ack

data

stable

data

can

change

data

stable

data

can

change

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

R/~W

Control Byte

Chip / Block

Select Bits

S 1 0 1 0 0

Control Byte

Single Byte Addressing Double Byte Addressing

Address Byte

Address Low

Byte

Address High

Byte

0 0 0

R/~W

Chip / Block

Select Bits

S 1 0 1 0

Control Byte

S 1 0 1 0

Control Byte

Single Byte Addressing Read Double Byte Addressing Read

0 0 01

Data Byte

P 1

Data Byte

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

Control Byte

S1010

Control Byte

Single Byte Addressing Sequential Reads

000

Data Byte

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

Data Byte

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

...

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

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

(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

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

Write

E2P_CMD

Read

E2P_CMD

EPC_BUSY = 0

EEPROM Read

Idle

Write

E2P_CMD

Read

E2P_CMD

Read

E2P_DATA

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

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

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

Load PHY registers with

current straps

Load PHY registers with

current straps

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

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

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

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

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

(little endian).

Figure 8.8 I2C Slave Addressing

R/~W

Control Byte

Address Byte

Start or

Stop or

Data [31]

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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

Control Byte

Single Register Read

Data Byte...

Data Byte

Data 1 Byte

Address Byte

Control Byte

Address Byte

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

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

Data Byte

Address Byte

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

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

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

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

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.

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

CODE

PHY

ADDRESS

Note 10.1

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

WRITE 32 1’s 01 01 1AAAA

9876

AAAAA

54321

10 DDDDDDDDDDDDDDDD

1111110000000000

5432109876543210

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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

CODE

PHY

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

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

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

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

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)

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)

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)

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

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

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

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

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

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

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

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

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

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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

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

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

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

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

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

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

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

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

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

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

(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

(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

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

WO 00000000h

Table 13.4 Switch Fabric CSR to SWITCH_CSR_DIRECT_DATA Address Range Map

SWITCH FABRIC CSR

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)

SWITCH FABRIC CSR

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)

SWITCH FABRIC CSR

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

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.

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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

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

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

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

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

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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

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

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

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

Note 13.27 IEEE allows a value of zero in each of the 32-bits of the PHY Identifier.

Offset:

Index (decimal):

1C8h

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

Note 13.29 IEEE allows a value of zero in each of the 32-bits of the PHY Identifier.

Offset:

Index (decimal):

1CCh

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

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

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

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

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

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

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

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

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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DATASHEET

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

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

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

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

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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

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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

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

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

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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DATASHEET

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

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

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

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

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

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

(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

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

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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)

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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)

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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)

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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)

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)

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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)

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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)

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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

1856h SWE_INGRESS_REGEN_TBL_1 Switch Engine Port 1 Ingress VLAN Priority Regeneration

1857h SWE_INGRESS_REGEN_TBL_2 Switch Engine Port 2 Ingress VLAN Priority Regeneration

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)

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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)

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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)

Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII

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DATASHEET

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

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.

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.

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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DATASHEET

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

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.

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)

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

Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII

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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)

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.

BITS DESCRIPTION TYPE DEFAULT

31:7 RESERVED RO -

6Buffer Manager Interrupt (BM)

Set when any unmasked bit in the Buffer Manager Interrupt Pending

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

Small Form Factor Three Port 10/100 Managed Ethernet Switch with Dual MII/RMII/Turbo MII

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DATASHEET

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.

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.

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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DATASHEET

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.

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.

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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DATASHEET

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.

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.

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DATASHEET

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.

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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DATASHEET

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.

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.

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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.

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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DATASHEET

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.

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.

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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DATASHEET

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.

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.

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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DATASHEET

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.

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.

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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DATASHEET

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.

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.

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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DATASHEET

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.

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.

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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DATASHEET

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.

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.

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.

RC 00000000h

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DATASHEET

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.

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.

RC 00000000h

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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.

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.

RC 00000000h

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DATASHEET

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.

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.

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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DATASHEET

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.

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.

RC 00000000h

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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.

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.

RC 00000000h

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DATASHEET

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.

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.

RC 00000000h

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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.

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.

RC 00000000h

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DATASHEET

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.

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.

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.

RC 00000000h

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DATASHEET

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.

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.

RC 00000000h

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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.

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.

RC 00000000h

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DATASHEET

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.

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.

RC 00000000h

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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.

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.

RC 00000000h

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DATASHEET

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.

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.

RC 00000000h

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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.

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.

RC 00000000h

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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.

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.

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.

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.

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.

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.

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.

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.

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.

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).

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).

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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).

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

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

the Switch Engine ALR Read Data 1 Register (SWE_ALR_RD_DAT_1) are set.

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).

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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

set.

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.

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.

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.

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13.4.3.7 Switch Engine ALR Configuration Register (SWE_ALR_CFG)

This register controls the ALR aging timer duration.

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

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.

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.

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).

15 Member Port 1

See description for Member Port 2.

14 Un-Tag Port 1

See description for Un-Tag Port 2.

13 Member Port 0

See description for Member Port 2.

12 Un-Tag Port 0

See description for Un-Tag Port 2.

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.

BITS DESCRIPTION TYPE DEFAULT

31:18 RESERVED RO -

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