LAN9221I-ABZJ - MICROCHIP - Datasheet.Directory

SMSC LAN9221/LAN9221i DATASHEET Revision 2.9 (03-01-12)

Datasheet

PRODUCT FEATURES

LAN9221/LAN9221i

High-Performance 16-bit Non-PCI

10/100 Ethernet Controller with

Variable Voltage I/O

Highlights

Optimized for high performance applications

Efficient architecture with low CPU overhead

Easily interfaces to most 16-bit embedded CPU’s

1.8V to 3.3V variable voltage I/O accommodates wide

range of I/O signalling without voltage level shifters

Integrated PHY with HP Auto-MDIX support

Integrated checksum offload engine helps reduce

CPU load

Low pin count and small body size package for small

form factor system designs

Target Applications

Cable, satellite, and IP set-top boxes

Digital video recorders and DVD recorder/players

Digital TV

Digital media clients/servers and home gateways

Video-over IP solutions, IP PBX & video phones

Wireless routers & access points

High-end audio distribution systems

Key Benefits

Non-PCI Ethernet controller for high performance

applications

— 16-bit interface with fast bus cycle times

— Burst-mode read support

Minimizes dropped packets

— Internal buffer memory can store over 200 packets

— Automatic PAUSE and back-pressure flow control

Minimizes CPU overhead

— Supports Slave-DMA

— Interrupt Pin with Programmable Hold-off timer

Reduces system cost and increases design flexibility

SRAM-like interface easily interfaces to most

embedded CPU’s or SoC’s

Reduced Power Modes

— Numerous power management modes

— Wake on LAN

— Magic packet wakeup

— Wakeup indicator event signal

— Link Status Change

Single chip Ethernet controller

— Fully compliant with IEEE 802.3/802.3u standards

— Integrated Ethernet MAC and PHY

— 10BASE-T and 100BASE-TX support

— Full- and Half-duplex support

— Full-duplex flow control

— Backpressure for half-duplex flow control

— Preamble generation and removal

— Automatic 32-bit CRC generation and checking

— Automatic payload padding and pad removal

— Loop-back modes

Flexible address filtering modes

— One 48-bit perfect address

— 64 hash-filtered multicast addresses

— Pass all multicast

— Promiscuous mode

— Inverse filtering

— Pass all incoming with status report

— Disable reception of broadcast packets

Integrated 10/100 Ethernet PHY

— Supports HP Auto-MDIX

— Auto-negotiation

— Supports energy-detect power down

Host bus interface

— Simple, SRAM-like interface

— 16-bit data bus

— 16Kbyte FIFO with flexible TX/RX allocation

— One configurable host interrupt

Miscellaneous features

— Small form factor, 56-pin QFN lead-free RoHS

Compliant package

— Integrated 1.8V regulator

— Integrated checksum offload engine

— Mixed endian support

— General Purpose Timer

— Optional EEPROM interface

— Support for 3 status LEDs multiplexed with

Programmable GPIO signals

Single 3.3V Power Supply with Variable Voltage I/O

Commercial and Industrial Temperature Support

Order Number(s):

LAN9221-ABZJ for 56-pin, QFN Lead-free RoHS Compliant package (0 to +70°C Temp Range)

LAN9221i-ABZJ for 56-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

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O

Datasheet

Revision 2.9 (03-01-12) 2SMSC LAN9221/LAN9221i

DATASHEET

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.

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O

Datasheet

SMSC LAN9221/LAN9221i 3Revision 2.9 (03-01-12)

DATASHEET

Table of Contents

Chapter 1 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

1.1 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

1.2 Internal Block Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

1.3 10/100 Ethernet PHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

1.4 10/100 Ethernet MAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

1.5 Receive and Transmit FIFOs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

1.6 Interrupt Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

1.7 GPIO Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

1.8 Serial EEPROM Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

1.9 Power Management Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

1.10 General Purpose Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

1.11 Host Bus Interface (SRAM Interface) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Chapter 2 Pin Description and Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2.1 Pin List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

2.2 External Pull-Up/Pull-Down Resistors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.3 Buffer Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Chapter 3 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

3.1 10/100 Ethernet MAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

3.2 Flow Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

3.2.1 Full-Duplex Flow Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

3.2.2 Half-Duplex Flow Control (Backpressure) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

3.2.3 Virtual Local Area Network (VLAN) Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

3.3 Address Filtering Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

3.4 Filtering Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

3.4.1 Perfect Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

3.4.2 Hash Only Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

3.5 Wake-up Frame Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

3.5.1 Magic Packet Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

3.6 Checksum Offload Engines (COE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

3.6.1 Receive Checksum Offload Engine (RXCOE). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

3.6.2 Transmit Checksum Offload Engine (TXCOE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

3.7 Host Bus Operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

3.7.1 Bus Writes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

3.7.2 Bus Reads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

3.7.3 Mixed Endian Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

3.7.4 Word Swap Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

3.8 General Purpose Timer (GP Timer) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

3.9 EEPROM Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

3.9.1 MAC Address Auto-Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

3.9.2 EEPROM Host Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

3.10 Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

3.10.1 System Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

3.10.2 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

3.10.3 Internal PHY Power-Down Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

3.11 Detailed Reset Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

3.11.1 Hardware Reset Input (nRESET) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

3.11.2 Resume Reset Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

3.11.3 Soft Reset (SRST) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

3.11.4 PHY Reset Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O

Datasheet

Revision 2.9 (03-01-12) 4SMSC LAN9221/LAN9221i

DATASHEET

3.12 TX Data Path Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

3.12.1 TX Buffer Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

3.12.2 TX Command Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

3.12.3 TX Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

3.12.4 TX Status Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

3.12.5 Calculating Actual TX Data FIFO Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

3.12.6 Transmit Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

3.12.7 Transmitter Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

3.12.8 Stopping and Starting the Transmitter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

3.13 RX Data Path Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

3.13.1 RX Slave PIO Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

3.13.2 RX Packet Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

3.13.3 RX Status Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

3.13.4 Stopping and Starting the Receiver. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

3.13.5 Receiver Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Chapter 4 Internal Ethernet PHY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

4.1 Top Level Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

4.2 100Base-TX Transmit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

4.2.1 4B/5B Encoding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

4.2.2 Scrambling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

4.2.3 NRZI and MLT3 Encoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

4.2.4 100M Transmit Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

4.2.5 100M Phase Lock Loop (PLL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

4.3 100Base-TX Receive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

4.3.1 100M Receive Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

4.3.2 Equalizer, Baseline Wander Correction and Clock and Data Recovery . . . . . . . . . . . . . 70

4.3.3 NRZI and MLT-3 Decoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

4.3.4 Descrambling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

4.3.5 Alignment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

4.3.6 5B/4B Decoding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

4.4 10Base-T Transmit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

4.4.1 10M Transmit Data across the internal MII bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

4.4.2 Manchester Encoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

4.4.3 10M Transmit Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

4.5 10Base-T Receive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

4.5.1 10M Receive Input and Squelch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

4.5.2 Manchester Decoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

4.5.3 Jabber Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

4.6 Auto-negotiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

4.7 Parallel Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

4.7.1 Re-starting Auto-negotiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

4.7.2 Disabling Auto-negotiation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

4.7.3 Half vs. Full-Duplex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

4.8 HP Auto-MDIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Chapter 5 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

5.1 Register Nomenclature and Access Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

5.2 RX and TX FIFO Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

5.2.1 RX FIFO Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

5.2.2 TX FIFO Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

5.3 System Control and Status Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

5.3.1 ID_REV—Chip ID and Revision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

5.3.2 IRQ_CFG—Interrupt Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O

Datasheet

SMSC LAN9221/LAN9221i 5Revision 2.9 (03-01-12)

DATASHEET

5.3.3 INT_STS—Interrupt Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

5.3.4 INT_EN—Interrupt Enable Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

5.3.5 BYTE_TEST—Byte Order Test Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

5.3.6 FIFO_INT—FIFO Level Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

5.3.7 RX_CFG—Receive Configuration Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

5.3.8 TX_CFG—Transmit Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

5.3.9 HW_CFG—Hardware Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

5.3.10 RX_DP_CTRL—Receive Datapath Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

5.3.11 RX_FIFO_INF—Receive FIFO Information Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

5.3.12 TX_FIFO_INF—Transmit FIFO Information Register . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

5.3.13 PMT_CTRL— Power Management Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

5.3.14 GPIO_CFG—General Purpose IO Configuration Register . . . . . . . . . . . . . . . . . . . . . . . 95

5.3.15 GPT_CFG-General Purpose Timer Configuration Register . . . . . . . . . . . . . . . . . . . . . . 96

5.3.16 GPT_CNT-General Purpose Timer Current Count Register . . . . . . . . . . . . . . . . . . . . . . 97

5.3.17 WORD_SWAP—Word Swap Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

5.3.18 FREE_RUN—Free-Run 25MHz Counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

5.3.19 RX_DROP– Receiver Dropped Frames Counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

5.3.20 MAC_CSR_CMD – MAC CSR Synchronizer Command Register . . . . . . . . . . . . . . . . . 99

5.3.21 MAC_CSR_DATA – MAC CSR Synchronizer Data Register . . . . . . . . . . . . . . . . . . . . . 99

5.3.22 AFC_CFG – Automatic Flow Control Configuration Register . . . . . . . . . . . . . . . . . . . . 100

5.3.23 E2P_CMD – EEPROM Command Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

5.3.24 E2P_DATA – EEPROM Data Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

5.4 MAC Control and Status Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

5.4.1 MAC_CR—MAC Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

5.4.2 ADDRH—MAC Address High Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

5.4.3 ADDRL—MAC Address Low Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

5.4.4 HASHH—Multicast Hash Table High Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

5.4.5 HASHL—Multicast Hash Table Low Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

5.4.6 MII_ACC—MII Access Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

5.4.7 MII_DATA—MII Data Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

5.4.8 FLOW—Flow Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

5.4.9 VLAN1—VLAN1 Tag Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

5.4.10 VLAN2—VLAN2 Tag Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

5.4.11 WUFF—Wake-up Frame Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

5.4.12 WUCSR—Wake-up Control and Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

5.4.13 COE_CR—Checksum Offload Engine Control Register . . . . . . . . . . . . . . . . . . . . . . . . 116

5.5 PHY Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

5.5.1 Basic Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

5.5.2 Basic Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

5.5.3 PHY Identifier 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

5.5.4 PHY Identifier 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

5.5.5 Auto-negotiation Advertisement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

5.5.6 Auto-negotiation Link Partner Ability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

5.5.7 Auto-negotiation Expansion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

5.5.8 Mode Control/Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

5.5.9 Special Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

5.5.10 Special Control/Status Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124

5.5.11 Interrupt Source Flag. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125

5.5.12 Interrupt Mask . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125

5.5.13 PHY Special Control/Status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126

Chapter 6 Timing Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

6.1 Equivalent Test Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

6.2 Host Interface Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O

Datasheet

Revision 2.9 (03-01-12) 6SMSC LAN9221/LAN9221i

DATASHEET

6.2.1 Special Restrictions on Back-to-Back Write/Read Cycles . . . . . . . . . . . . . . . . . . . . . . . 128

6.2.2 Special Restrictions on Back-to-Back Read Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

6.3 PIO Reads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

6.4 PIO Burst Reads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

6.5 RX Data FIFO Direct PIO Reads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

6.6 RX Data FIFO Direct PIO Burst Reads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

6.7 PIO Writes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

6.8 TX Data FIFO Direct PIO Writes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

6.9 Power Sequence Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

6.10 Reset Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

6.11 EEPROM Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

Chapter 7 Operational Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

7.1 Absolute Maximum Ratings*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

7.2 Operating Conditions** . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

7.3 Power Consumption (Device Only). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140

7.4 Power Consumption (Device and System Components) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

7.5 Worst Case Current Consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

7.6 DC Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

7.7 Clock Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

Chapter 8 Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

8.1 56-QFN Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

Chapter 9 Datasheet Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O

Datasheet

SMSC LAN9221/LAN9221i 7Revision 2.9 (03-01-12)

DATASHEET

List of Figures

Figure 1.1 System Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Figure 1.2 Internal Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 2.1 56-QFN Pin Configuration (Top View) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 3.1 VLAN Frame . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Figure 3.2 RXCOE Checksum Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Figure 3.3 Type II Ethernet Frame . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Figure 3.4 Ethernet Frame with VLAN Tag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Figure 3.5 Ethernet Frame with Length Field and SNAP Header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Figure 3.6 Ethernet Frame with VLAN Tag and SNAP Header. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 3.7 Ethernet Frame with Multiple VLAN Tags and SNAP Header . . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 3.8 LAN9221/LAN9221i Host Data Path Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Figure 3.9 FIFO Access Byte Ordering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Figure 3.10 EEPROM Access Flow Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Figure 3.11 EEPROM ERASE Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Figure 3.12 EEPROM ERAL Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Figure 3.13 EEPROM EWDS Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Figure 3.14 EEPROM EWEN Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Figure 3.15 EEPROM READ Cycle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Figure 3.16 EEPROM WRITE Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Figure 3.17 EEPROM WRAL Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Figure 3.18 PME and PME_INT Signal Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Figure 3.19 Simplified Host TX Flow Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Figure 3.20 TX Buffer Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Figure 3.21 TX Example 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Figure 3.22 TX Example 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

Figure 3.23 TX Example 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Figure 3.24 Host Receive Routine Using Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Figure 3.25 Host Receive Routine with Polling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Figure 3.26 RX Packet Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Figure 3.27 RX Packet Format with RX Checksum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Figure 4.1 100Base-TX Data Path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Figure 4.2 Receive Data Path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Figure 4.3 Direct Cable Connection vs. Cross-over Cable Connection . . . . . . . . . . . . . . . . . . . . . . . . . 76

Figure 5.1 Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Figure 5.2 Example ADDRL, ADDRH and EEPROM Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

Figure 6.1 Equivalent Test Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

Figure 6.2 PIO Read Cycle Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

Figure 6.3 PIO Burst Read Cycle Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

Figure 6.4 RX Data FIFO Direct PIO Read Cycle Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

Figure 6.5 RX Data FIFO Direct PIO Burst Read Cycle Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

Figure 6.6 PIO Write Cycle Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

Figure 6.7 TX Data FIFO Direct PIO Write Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Figure 6.8 Power Sequence Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

Figure 6.9 Reset Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Figure 6.10 EEPROM Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

Figure 8.1 56 Pin QFN Package Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

Figure 8.2 56 Pin QFN Recommended PCB Land Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O

Datasheet

Revision 2.9 (03-01-12) 8SMSC LAN9221/LAN9221i

DATASHEET

List of Tables

Table 2.1 Host Bus Interface Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Table 2.2 LAN Interface Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Table 2.3 Serial EEPROM Interface Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Table 2.4 System and Power Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Table 2.5 56-QFN Package Pin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Table 2.6 External Pull-Up/Pull-Down Resistor Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Table 2.7 Buffer Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Table 3.1 Address Filtering Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Table 3.2 Wake-Up Frame Filter Register Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Table 3.3 Filter i Byte Mask Bit Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Table 3.4 Filter i Command Bit Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Table 3.5 Filter i Offset Bit Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Table 3.6 Filter i CRC-16 Bit Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Table 3.7 TX Checksum Preamble . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Table 3.8 Endian Ordering Logic Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Table 3.9 Required EECLK Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Table 3.10 Power Management States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Table 3.11 Reset Sources and Affected Circuitry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Table 3.12 TX Command 'A' Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Table 3.13 TX Command 'B' Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Table 3.14 TX DATA Start Offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Table 4.1 4B/5B Code Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Table 4.2 CRS Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Table 5.1 Direct Address Register Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Table 5.2 RX Alignment Bit Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Table 5.3 Valid TX/RX FIFO Allocations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

Table 5.4 EEPROM Enable Bit Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

Table 5.5 Backpressure Duration Bit Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

Table 5.6 MAC CSR Register Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

Table 5.7 ADDRL, ADDRH and EEPROM Byte Ordering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

Table 5.8 LAN9221/LAN9221i PHY Control and Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

Table 5.9 MODE Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

Table 6.1 Read After Write Timing Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

Table 6.2 Read After Read Timing Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

Table 6.3 PIO Read Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

Table 6.4 PIO Burst Read Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

Table 6.5 RX Data FIFO Direct PIO Read Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

Table 6.6 RX Data FIFO Direct PIO Burst Read Cycle Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

Table 6.7 PIO Write Cycle Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

Table 6.8 TX Data FIFO Direct PIO Write Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Table 6.9 Power Sequence Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

Table 6.10 Reset Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Table 6.11 EEPROM Timing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

Table 7.1 Power Consumption Device Only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140

Table 7.2 Power Consumption Device and System Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

Table 7.3 Maximum Supply Current Characteristics VDDVARIO=3.3V + 300mV. . . . . . . . . . . . . . . . . 142

Table 7.4 Maximum Supply Current Characteristics VDDVARIO=2.5V + 10%. . . . . . . . . . . . . . . . . . . 142

Table 7.5 Maximum Supply Current Characteristics VDDVARIO=1.8V + 10%. . . . . . . . . . . . . . . . . . . 142

Table 7.6 I/O Buffer Characteristics VDDVARIO=3.3V +/- 300mV . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Table 7.7 I/O Buffer Characteristics VDDVARIO=2.5V +/- 10% . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Table 7.8 I/O Buffer Characteristics VDDVARIO=1.8V +/- 10% . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

Table 7.9 100BASE-TX Transceiver Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

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Table 7.10 10BASE-T Transceiver Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

Table 7.11 LAN9221/LAN9221i Crystal Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

Table 8.1 56 Pin QFN Package Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

Table 9.1 Customer Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

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Chapter 1 General Description

The LAN9221/LAN9221i is a full-featured, single-chip 10/100 Ethernet controller designed for

embedded applications where performance, flexibility, ease of integration and system cost control are

required. The LAN9221/LAN9221i has been specifically designed to provide high performance and

throughput for 16-bit applications. The LAN9221/LAN9221i is fully IEEE 802.3 10BASE-T and 802.3u

100BASE-TX compliant, and supports HP Auto-MDIX. The variable voltage I/O signals of the

LAN9221/LAN9221i accommodate lower voltage I/O signalling without the need for voltage level

shifters.

The LAN9221/LAN9221i includes an integrated Ethernet MAC and PHY with a high-performance

SRAM-like slave interface. The simple, yet highly functional host bus interface provides a glue-less

connection to most common 16-bit microprocessors and microcontrollers as well as 32-bit

microprocessors with a 16-bit external bus. The integrated checksum offload engines enable the

automatic generation of the 16-bit checksum for received and transmitted Ethernet frames, offloading

the task from the CPU. The LAN9221/LAN9221i also includes large transmit and receive data FIFOs

to accommodate high latency applications. In addition, the LAN9221/LAN9221i memory buffer

architecture allows highly efficient use of memory resources by optimizing packet granularity.

Applications

The LAN9221/LAN9221i is well suited for many high-performance embedded applications, including:

Cable, satellite and IP set-top boxes

High-end audio distribution systems

Digital video recorders

DVD Recorders/Players

Digital TV

Digital media clients/servers

Home gateways

Industrial and embedded systems with extended temperature support

The LAN9221/LAN9221i also supports features which reduce or eliminate packet loss. Its internal 16-

KByte SRAM can hold over 200 received packets. If the receive FIFO gets too full, the

LAN9221/LAN9221i can automatically generate flow control packets to the remote node, or assert

back-pressure on the remote node by generating network collisions.

The LAN9221/LAN9221i supports numerous power management and wakeup features. The

LAN9221/LAN9221i can be placed in a reduced power mode and can be programmed to issue an

external wake signal via several methods, including “Magic Packet”, “Wake on LAN” and “Link Status

Change”. This signal is ideal for triggering system power-up using remote Ethernet wakeup events.

The device can be removed from the low power state via a host processor command.

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1.1 Block Diagram

The SMSC LAN9221/LAN9221i integrated 10/100 MAC/PHY controller is a peripheral chip that

performs the function of translating parallel data from a host controller into Ethernet packets. The

LAN9221/LAN9221i Ethernet MAC/PHY controller is designed and optimized to function in an

embedded environment. All communication is performed with programmed I/O transactions using the

simple SRAM-like host interface bus.

The diagram shown above, describes a typical system configuration of the LAN9221/LAN9221i in a

typical embedded environment.

The LAN9221/LAN9221i is a general purpose, platform independent, Ethernet controller. The

LAN9221/LAN9221i consists of four major functional blocks. The four blocks are:

10/100 Ethernet PHY

10/100 Ethernet MAC

RX/TX FIFOs

Host Bus Interface (HBI)

Figure 1.1 System Block Diagram

Microprocessor/

Microcontroller

LAN9221/

LAN9221i

Magnetics Ethernet

System

Peripherals

System Memory

EEPROM

(Optional)

LEDS/

GPIO

25MHz

XTAL

System Bus

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1.2 Internal Block Overview

This section provides an overview of each of these functional blocks as shown in Figure 1.2, "Internal

Block Diagram".

Figure 1.2 Internal Block Diagram

1.3 10/100 Ethernet PHY

The LAN9221/LAN9221i integrates an IEEE 802.3 physical layer for twisted pair Ethernet applications.

The PHY can be configured for either 100 Mbps (100BASE-TX) or 10 Mbps (10BASE-T) Ethernet

operation in either full or half duplex configurations. The PHY block supports HP Auto-MDIX and auto-

negotiation.

Minimal external components are required for the utilization of the Integrated PHY.

1.4 10/100 Ethernet MAC

The transmit and receive data paths are separate within the MAC allowing the highest performance

especially in full duplex mode. The data paths connect to the PIO interface Function via separate

busses to increase performance. Payload data as well as transmit and receive status is passed on

these busses.

A third internal bus is used to access the MAC’s Control and Status Registers (CSR’s). This bus is

accessible from the host through the PIO interface function.

On the backend, the MAC interfaces with the internal 10/100 PHY through a MII (Media Independent

Interface) port internal to the LAN9221/LAN9221i. The MAC CSR's also provide a mechanism for

accessing the PHY’s internal registers through the internal SMI (Serial Management Interface) bus.

The MAC Interface Layer (MIL), within the MAC, contains a 2K Byte transmit and a 128 Byte receive

FIFO which is separate from the TX and RX FIFOs. The FIFOs within the MAC are not directly

accessible from the host interface. The differentiation between the TX/RX FIFO memory buffers and

the MAC buffers is that when the transmit or receive packets are in the MAC buffers, the host no longer

10/100

Ethernet

PHY

10/100

Ethernet

MAC

2kB to 14kB

Configurable TX FIFO

2kB to 14kB

Configurable RX FIFO

Interrupt

Controller

GP Timer

PIO Controller

3.3V to 1.8V

Core Regulator PLL

25MHz

+3.3V

EEPROM

Controller

EEPROM

(Optional)

RX Status FIFO

TX Status FIFO

MIL - TX Elastic

Buffer - 2K bytes

MIL - RX Elastic

Buffer - 128 bytes

Power

Management

IRQ

FIFO_SEL

PME

Wakup Indicator

Host Bus Interface

(HBI)

16-bit SRAM I/F

RX Checksum

Offload Engine

TX Checksum

Offload Engine

LAN

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can control or access the TX or RX data. The MAC buffers (both TX and RX) are in effect the working

buffers of the Ethernet MAC logic. In the case of reception, the data must be moved first to the RX

FIFOs for the host to access the data. For TX operations, the MIL operates in store-and-forward mode

and will queue an entire frame before beginning transmission.

1.5 Receive and Transmit FIFOs

The Receive and Transmit FIFOs allow increased packet buffer storage to the MAC. The FIFOs are a

conduit between the host interface and the MAC through which all transmitted and received data and

status information is passed. Deep FIFOs allow a high degree of latency tolerance relative to the

various transport and OS software stacks thus reducing or minimizing overrun conditions. Like the

MAC, the FIFOs have separate receive and transmit data paths. In addition, the RX and TX FIFOs are

configurable in size, allowing increased flexibility.

1.6 Interrupt Controller

The LAN9221/LAN9221i supports a single programmable interrupt. The programmable nature of this

interrupt allows the user the ability to optimize performance dependent upon the application

requirement. Both the polarity and buffer type of the interrupt pin are configurable for the external

interrupt processing. The interrupt line can be configured as an open-drain output to facilitate the

sharing of interrupts with other devices. In addition, a programmable interrupt de-assertion interval is

provided.

1.7 GPIO Interface

A 3-bit GPIO and 2-bit GPO (Multiplexed on the EEPROM and LED Pins) interface is included in the

LAN9221/LAN9221i. It is accessible through the host bus interface via the CSRs. The GPIO signals

can function as inputs, push-pull outputs and open drain outputs. The GPIO’s (GPO’s are not

configurable) can also be configured to trigger interrupts with programmable polarity.

1.8 Serial EEPROM Interface

A serial EEPROM interface is included in the LAN9221/LAN9221i. The serial EEPROM is optional and

can be programmed with the LAN9221/LAN9221i MAC address. The LAN9221/LAN9221i can

optionally load the MAC address automatically after hardware reset, or soft reset.

1.9 Power Management Controls

The LAN9221/LAN9221i supports comprehensive array of power management modes to allow use in

power sensitive applications. Wake on LAN, Link Status Change and Magic Packet detection are

supported by the LAN9221/LAN9221i. An external PME (Power Management Event) interrupt is

provided to indicate detection of a wakeup event.

1.10 General Purpose Timer

The general-purpose timer has no dedicated function within the LAN9221/LAN9221i and may be

programmed to issue a timed interrupt.

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1.11 Host Bus Interface (SRAM Interface)

The host bus interface provides a FIFO interface for the transmit and receive data paths, as well as

an interface for the LAN9221/LAN9221i Control and Status Registers (CSR’s).

The host bus interface is the primary bus for connection to the embedded host system. This interface

models an asynchronous SRAM. TX FIFO, RX FIFO, and CSR’s are accessed through this interface.

Programmed I/O transactions are supported.

The LAN9221/LAN9221i host bus interface supports 16-bit bus transfers. Internally, all data paths are

32-bits wide. The LAN9221/LAN9221i can be interfaced to either Big-Endian or Little-Endian

processors and includes mixed endian support for FIFO accesses.

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Chapter 2 Pin Description and Configuration

Figure 2.1 56-QFN Pin Configuration (Top View)

VSS

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

**DENOTES A MULTIFUNCTION PIN

NOTE: When HP Auto-MDIX is activated, the TPO+/- pins can function as TPI+/- and vice-versa

SMSC

LAN9221/LAN9221i

56-QFN

(TOP VIEW)

IRQ

nRESET

TEST

FIFO_SEL

GPIO2/nLED3**

GPIO1/nLED2**

GPIO0/nLED1**

VDD18CORE

VDD33REG

PME

EECLK/GPO4**

EECS

EEDIO/GPO3**

VDD18CORE

VDDVARIO

TPO-

TPO+

VDD33A

TPI-

TPI+

VDD33A

EXRES

VDD33A

AMDIX_EN

VDD18A

XTAL2

XTAL1/CLKIN**

VDDVARIO

D10

VDDVARIO

D11

D12

D13

D14

D15

VDDVARIO

nCS

nWR

nRD

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2.1 Pin List

Note: The pin names for the twisted pair pins shown above apply to a normal connection. If HP Auto-

MDIX is enabled and a reverse connection is detected, or a reverse connection is manually

selected, the input pins become outputs, and vice-versa, as indicated in the descriptions.

Table 2.1 Host Bus Interface Signals

NAME SYMBOL

BUFFER

TYPE

PINS DESCRIPTION

Host Data D[15:0] VIS/VO8 16 Bi-directional data port.

Host Address A[7:1] VIS 7 7-bit Address Port. Used to select Internal CSR’s and

TX and RX FIFOs.

Read Strobe nRD VIS 1 Active low strobe to indicate a read cycle.

Write Strobe nWR VIS 1 Active low strobe to indicate a write cycle. This signal,

qualified with nCS, is also used to wakeup the

LAN9221/LAN9221i when it is in a reduced power

state.

Chip Select nCS VIS 1 Active low signal used to qualify read and write

operations. This signal qualified with nWR is also used

to wakeup the LAN9221/LAN9221i when it is in a

reduced power state.

Interrupt

Request

IRQ VO8/

VOD8

1 Programmable Interrupt request. Programmable

polarity, source and buffer types.

FIFO Select FIFO_SEL VIS 1 When driven high all accesses to the

LAN9221/LAN9221i are to the RX or TX Data FIFOs.

In this mode, the A[7:3] upper address inputs are

ignored.

Table 2.2 LAN Interface Signals

NAME SYMBOL

BUFFER

TYPE

NUM

PINS DESCRIPTION

TPO+ TPO+ AO 1 Transmit Positive Output (normal)

Receive Positive Input (reversed)

TPO- TPO- AO 1 Transmit Negative Output (normal)

Receive Negative Input (reversed)

TPI+ TPI+ AI 1 Receive Positive Input (normal)

Transmit Positive Input (reversed)

TPI- TPI- AI 1 Receive Negative Input (normal)

Transmit Negative Output (reversed)

PHY External Bias

Resistor

EXRES AI 1 Must be connected to ground through a 12.4K

ohm 1% resistor.

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Table 2.3 Serial EEPROM Interface Signals

NAME SYMBOL

BUFFER

TYPE

NUM

PINS DESCRIPTION

EEPROM Data,

GPO3, TX_EN,

TX_CLK

EEDIO/GPO3/

TX_EN/TX_CLK

VIS/VO8 1 EEPROM Data: This bi-directional pin can be

connected to a serial EEPROM DIO. This is

optional.

General Purpose Output 3: This pin can also

function as a general purpose output, or it can

be configured to monitor the TX_EN or

TX_CLK signals on the internal MII port. When

configured as a GPO signal, or as a

TX_EN/TX_CLK monitor, the EECS pin is

deasserted so as to never unintentionally

access the serial EEPROM. This signal cannot

function as a general-purpose input.

EEPROM Chip

Select

EECS VO8 1 Serial EEPROM chip select.

EEPROM Clock,

GPO4 RX_DV,

RX_CLK

EECLK/GPO4/

RX_DV/RX_CLK

VO8

(PU)

1EEPROM Clock: Serial EEPROM Clock pin.

General Purpose Output 4: This pin can also

function as a general-purpose output, or it can

be configured to monitor the RX_DV or

RX_CLK signals on the internal MII port. When

configured as a GPO signal, or as an

RX_DV/RX_CLK monitor, the EECS pin is

deasserted so as to never unintentionally

access the serial EEPROM. This signal cannot

function as a general-purpose input.

Note: When the EEPROM interface is not

used, the EECLK pin must be left

unconnected.

Note: When operating at reduced

VDDVARIO voltage levels (less than

3.0V), this pin must be pulled-up with

an external resistor. Refer to Section

2.2, "External Pull-Up/Pull-Down

Resistors" for more information.

Note: This pin must not be pulled low by an

external resistor or driven low

externally under any conditions.

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Table 2.4 System and Power Signals

NAME SYMBOL

BUFFER

TYPE

NUM

PINS DESCRIPTION

Crystal 1, Clock In XTAL1/CLKIN lCLK 1 External 25MHz Crystal Input. This pin can also

be connected to single-ended TTL oscillator

(CLKIN). If this method is implemented, XTAL2

should be left unconnected.

Crystal 2 XTAL2 OCLK 1 External 25MHz Crystal output.

Reset nRESET VIS

(PU)

1 Active-low reset input. Resets all logic and

registers within the LAN9221/LAN9221i. This

signal is pulled high with a weak internal pull-up

resistor.

Note: The LAN9221/LAN9221i must be reset

on power-up via nRESET or following

power-up via a soft reset (SRST). The

LAN9221/LAN9221i must always be

read at least once after reset, or upon

return from a power-saving state or

write operations will not function. See

Section 3.11, "Detailed Reset

Description," on page 47 for additional

information

Note: When operating at reduced

VDDVARIO voltage levels (less than

3.0V), this pin must be pulled-high to

a valid level with an external resistor

or must be driven as an input. Refer to

Section 2.2, "External Pull-Up/Pull-

Down Resistors" for more information.

Wakeup Indicator PME VO8/

VOD8

1 When programmed to do so, is asserted when

the LAN9221/LAN9221i detects a wake event

and is requesting the system to wake up from

the associated sleep state. The polarity and

buffer type of this signal is programmable.

Note: Detection of a Power Management

Event, and assertion of the PME

signal will not wakeup the

LAN9221/LAN9221i. The

LAN9221/LAN9221iwill only wake up

when it detects a host write cycle

(assertion of nCS and nWR). Although

any write to the LAN9221/LAN9221i,

regardless of the data written, will

wake-up the device when it is in a

power-saving mode, it is required that

the BYTE_TEST register be used for

this purpose.

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Auto-MDIX Enable AMDIX_EN VIS

(PU)

1 Enables Auto-MDIX. Pull high or leave

unconnected to enable Auto-MDIX, pull low to

disable Auto-MDIX.

Note: When operating at reduced

VDDVARIO voltage levels (less than

3.0V), this pin must be pulled to a valid

level with an external resistor. Refer to

Section 2.2, "External Pull-Up/Pull-

Down Resistors" for more information.

Test TEST VIS

(PD)

1 Reserved for internal test purposes only.

Note: When operating at a reduced

VDDVARIO voltage (less than 3.0V),

this pin must be connected to ground

or pulled-low with an external resistor.

When VDDVARIO = 3.3V, this pin may

be left unconnected. Refer to Section

2.2, "External Pull-Up/Pull-Down

Resistors" for more information.

General Purpose

I/O data,

nLED1 (Speed

Indicator),

nLED2 (Link &

Activity Indicator),

nLED3 (Full-

Duplex

Indicator).

GPIO[2:0]/

nLED[3:1]

VIS/

VO12/

VOD12

3General Purpose I/O data: These three

general-purpose signals are fully programmable

as either push-pull output, open-drain output or

input by writing the GPIO_CFG configuration

as GP LED connections.

GPIO signals are Schmitt-triggered inputs.

When configured as LED outputs these signals

are open-drain.

nLED1 (Speed Indicator). This signal is driven

low when the operating speed is 100Mb. During

auto-negotiation, when the cable is

disconnected, and during 10Mbs operation, this

signal is driven high.

nLED2 (Link & Activity Indicator). This signal

is driven low (LED on) when the

LAN9221/LAN9221i detects a valid link. This

signal is pulsed high (LED off) for 80mS

whenever transmit or receive activity is

detected. This signal is then driven low again

for a minimum of 80mS, after which time it will

repeat the process if TX or RX activity is

detected. Effectively, LED2 is activated solid for

a link. When transmit or receive activity is

sensed LED2 will flash as an activity indicator.

nLED3 (Full-Duplex Indicator). This signal is

driven low when the link is operating in full-

duplex mode.

Variable Voltage

I/O Power

VDDVARIO P 4 Variable Voltage I/O logic power supply pins.

Refer to Section 7.2, "Operating Conditions**,"

on page 139 for additional details.

Common Ground VSS P 1 pad Common Ground

+3.3V Regulator

Power Supply

VDD33REG P 1 +3.3V power supply for internal +1.8V regulator.

Table 2.4 System and Power Signals (continued)

NAME SYMBOL

BUFFER

TYPE

NUM

PINS DESCRIPTION

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+3.3V Analog

Power

VDD33A P 3 +3.3V analog power supply pins.

+1.8V Analog

Power

VDD18A P 1 +1.8V analog power supply pin. This pin must

be connected externally to VDD18CORE.

Core Voltage

Decoupling

VDD18CORE P 2 +1.8 V from internal core regulator. Both pins

must be connected together externally. Each

pin requires a 0.01uF decoupling capacitor. In

addition, pin 2 requires a bulk 4.7uF capacitor

(<2 Ohm ESR) in parallel. These pins must not

be used to supply power to other external

devices.

Table 2.5 56-QFN Package Pin Assignments

NUM PIN NAME

1 VDD33REG 15 nRD 29 D6 43 IRQ

2 VDD18CORE 16 nWR 30 VDDVARIO 44 TPO-

3 GPIO0/nLED1 17 nCS 31 D5 45 TPO+

4 GPIO1/nLED2 18 VDDVARIO 32 D4 46 VDD33A

5 GPIO2/nLED3 19 D15 33 D3 47 TPI-

6 A7 20 D14 34 D2 48 TPI+

7 A6 21 D13 35 D1 49 VDD33A

8 A5 22 D12 36 D0 50 EXRES

9 A4 23 D11 37 VDD18CORE 51 VDD33A

10 A3 24 VDDVARIO 38 EEDIO/GPO3 52 AMDIX_EN

11 A2 25 D10 39 EECS 53 VDD18A

12 A1 26 D9 40 EECLK/GPO4 54 XTAL2

13 FIFO_SEL 27 D8 41 PME 55 XTAL1/CLKIN

14 TEST 28 D7 42 nRESET 56 VDDVARIO

EXPOSED PAD

MUST BE CONNECTED TO VSS

Table 2.4 System and Power Signals (continued)

NAME SYMBOL

BUFFER

TYPE

NUM

PINS DESCRIPTION

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2.2 External Pull-Up/Pull-Down Resistors

As detailed in Ta b l e 2 . 6 , when using an external pull-up or pull-down resistor, the required value is

dependant on the operating voltage. Usage of recommended pull-up/pull-down resistor values is

required to ensure proper operation.

2.3 Buffer Types

Note 2.1 Sink and source capabilities are dependant on the VDDVARIO voltage. Refer to Section

7.6, "DC Electrical Specifications" for additional information.

Note 2.2 When operating at reduced VDDVARIO voltage levels (less than 3.0V), do not rely on

internal pull-up and pull-down resistors to determine signal state. Refer to Section 2.2,

"External Pull-Up/Pull-Down Resistors" and the individual signal descriptions in Section

2.1, "Pin List" for more information.

Table 2.6 External Pull-Up/Pull-Down Resistor Values

I/O VOLTAGE PULL-UP/PULL-DOWN RESISTOR VALUE (OHMS)

3.3V +/- 300mV 10K

2.5 +/- 10% 7.5K

1.8V +/- 10% 4.7K

Table 2.7 Buffer Types

TYPE DESCRIPTION

VIS Variable voltage input pin

VO12 Variable voltage output with 12mA sink and 12mA source (Note 2.1)

VOD12 Variable voltage open-drain output with 12mA sink (Note 2.1)

VO8 Variable voltage output 8mA symmetrical drive (Note 2.1)

VOD8 Variable voltage open-drain output with 8 mA sink (Note 2.1)

PU 50uA (typical) internal pull-up (Note 2.2)

PD 50uA (typical) internal pull-down (Note 2.2)

AI Analog input

AO Analog output

AIO Analog bi-directional

ICLK Crystal oscillator input pin

OCLK Crystal oscillator output pin

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Chapter 3 Functional Description

3.1 10/100 Ethernet MAC

The Ethernet Media Access controller (MAC) incorporates the essential protocol requirements for

operating an Ethernet/IEEE 802.3-compliant node and provides an interface between the host

subsystem and the internal Ethernet PHY. The MAC can operate in either 100-Mbps or 10-Mbps mode.

The MAC operates in both half-duplex and full-duplex modes. When operating in half-duplex mode,

the MAC complies fully with Section 4 of ISO/IEC 8802-3 (ANSI/IEEE standard) and ANSI/IEEE 802.3

standards. When operating in full-duplex mode, the MAC complies with IEEE 802.3x full-duplex

operation standard.

The MAC provides programmable enhanced features designed to minimize host supervision, bus

utilization, and pre- or post-message processing. These features include the ability to disable retries

after a collision, dynamic FCS (Frame Check Sequence) generation on a frame-by-frame basis,

automatic pad field insertion and deletion to enforce minimum frame size attributes, layer 3 checksum

calculation for transmit and receive operations, and automatic retransmission and detection of collision

frames.

The MAC can sustain transmission or reception of minimally-sized back-to-back packets at full line

speed with an interpacket gap (IPG) of 9.6 microseconds for 10 Mbps and 0.96 microseconds for 100

Mbps.

The primary attributes of the MAC Function are:

Transmit and receive message data encapsulation

Framing (frame boundary delimitation, frame synchronization)

Error detection (physical medium transmission errors)

Media access management

Medium allocation (collision detection, except in full-duplex operation)

Contention resolution (collision handling, except in full-duplex operation)

Flow control during full-duplex mode

Decoding of control frames (PAUSE command) and disabling the transmitter

Generation of control frames

Interface to the internal PHY.

Checksum offload engine for calculation of layer 3 transmit and receive checksum.

The transmit and receive data paths are separate within the LAN9221/LAN9221i from the MAC to host

interface allowing the highest performance, especially in full duplex mode. Payload data as well as

transmit and receive status are passed on these busses.

A third internal bus is used to access the MAC’s “Control and Status Registers” (CSR’s). This bus is

also accessible from the host.

On the backend, the MAC interfaces with the 10/100 PHY through an MII (Media Independent

Interface) port which is internal to the LAN9221/LAN9221i. The MAC CSR's also provide a mechanism

for accessing the PHY’s internal registers through the internal SMI (Serial Management Interface) bus.

The receive and transmit FIFOs allow increased packet buffer storage to the MAC. The FIFOs are a

conduit between the host interface and the MAC through which all transmitted and received data and

status information is passed. Deep FIFOs allow a high degree of latency tolerance relative to the

various transport and OS software stacks reducing and minimizing overrun conditions. Like the MAC,

the FIFOs have separate receive and transmit data paths.

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The LAN9221/LAN9221i can store up to 250 Ethernet packets utilizing FIFOs, totaling 16K bytes, with

a packet granularity of 4 bytes. This memory is shared by the RX and TX blocks and is configurable

in terms of allocation. This depth of buffer storage minimizes or eliminates receive overruns.

3.2 Flow Control

The LAN9221/LAN9221i Ethernet MAC supports full-duplex flow control using the pause operation and

control frame. It also supports half-duplex flow control using back pressure.

3.2.1 Full-Duplex Flow Control

The pause operation inhibits data transmission of data frames for a specified period of time. A Pause

operation consists of a frame containing the globally assigned multicast address (01-80-C2-00-00-01),

the PAUSE opcode, and a parameter indicating the quantum of slot time (512 bit times) to inhibit data

transmissions. The PAUSE parameter may range from 0 to 65,535 slot times. The Ethernet MAC logic,

on receiving a frame with the reserved multicast address and PAUSE opcode, inhibits data frame

transmissions for the length of time indicated. If a Pause request is received while a transmission is

in progress, then the pause will take effect after the transmission is complete. Control frames are

received and processed by the MAC and are passed on.

The MAC also transmits control frames (pause command) via both hardware and software control. The

software driver requests the MAC to transmit a control frame and gives the value of the PAUSE time

to be used in the control frame. The MAC Function constructs a control frame with the appropriate

values set in all the different fields (as defined in the 802.3x specification) and transmits the frame to

the MII interface. The transmission of the control frame is not affected by the current state of the Pause

timer value that is set because of a recently received control frame.

3.2.2 Half-Duplex Flow Control (Backpressure)

In half-duplex mode, back pressure is used for flow control. Whenever the receive buffer/FIFO

becomes full or crosses a certain threshold level, the MAC starts sending a Jam signal. The MAC

transmit logic enters a state at the end of current transmission (if any), where it waits for the beginning

of a received frame. Once a new frame starts, the MAC starts sending the jam signal, which will result

in a collision. After sensing the collision, the remote station will back off its transmission. The MAC

continues sending the jam to make other stations defer transmission. The MAC only generates this

collision-based back pressure when it receives a new frame, in order to avoid any late collisions.

3.2.3 Virtual Local Area Network (VLAN) Support

Virtual Local Area Networks or VLANs, as defined within the IEEE 802.3 standard, provide network

administrators one means of grouping nodes within a larger network into broadcast domains. To

implement a VLAN, four extra bytes are added to the basic Ethernet packet. As shown in Figure 3.1,

"VLAN Frame", the four bytes are inserted after the Source Address Field and before the Type/Length

field. The first two bytes of the VLAN tag identify the tag, and by convention are set to the value

0x8100. The last two bytes identify the specific VLAN associated with the packet; they also provide a

priority field.

The LAN9221/LAN9221i supports VLAN-tagged packets. The LAN9221/LAN9221i provides two

registers which are used to identify VLAN-tagged packets. One register should normally be set to the

conventional VLAN ID of 0x8100. The other register provides a way of identifying VLAN frames tagged

with a proprietary (not 0x8100) identifier. If a packet arrives bearing either of these tags in the two

bytes succeeding the Source Address field, the controller will recognize the packet as a VLAN-tagged

packet. In this case, the controller increases the maximum allowed packet size from 1518 to 1522

bytes (normally the controller filters packets larger than 1518 bytes). This allows the packet to be

received, and then processed by host software, or to be transmitted on the network.

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3.3 Address Filtering Functional Description

The Ethernet address fields of an Ethernet Packet, consists of two 6-byte fields: one for the destination

address and one for the source address. The first bit of the destination address signifies whether it is

a physical address or a multicast address.

The LAN9221/LAN9221i address check logic filters the frame based on the Ethernet receive filter mode

that has been enabled. Filter modes are specified based on the state of the control bits in Ta b l e 3 . 1 ,

"Address Filtering Modes", which shows the various filtering modes used by the Ethernet MAC

Function. These bits are defined in more detail in the “MAC Control Register”. Please refer to Section

5.4.1, "MAC_CR—MAC Control Register" for more information on this register.

If the frame fails the filter, the Ethernet MAC function does not receive the packet. The host has the

option of accepting or ignoring the packet.

Figure 3.1 VLAN Frame

Table 3.1 Address Filtering Modes

MCPAS PRMS INVFILT HO HPFILT DESCRIPTION

0 0 0 0 0 MAC address perfect filtering only

for all addresses.

0 0 0 0 1 MAC address perfect filtering for

physical address and hash filtering

for multicast addresses

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3.4 Filtering Modes

3.4.1 Perfect Filtering

This filtering mode passes only incoming frames whose destination address field exactly matches the

value programmed into the MAC Address High register and the MAC address low register. The MAC

address is formed by the concatenation of the above two registers in the MAC CSR Function.

3.4.2 Hash Only Filtering

This type of filtering checks for incoming Receive packets with either multicast or physical destination

addresses, and executes an imperfect address filtering against the hash table.

During imperfect hash filtering, the destination address in the incoming frame is passed through the

CRC logic and the upper six bits of the CRC register are used to index the contents of the hash table.

The hash table is formed by merging the register’s multicast hash table high and multicast hash table

low in the MAC CSR Function to form a 64-bit hash table. The most significant bit determines the

of 00000 selects Bit 0 of the multicast hash table low register and a value of 11111 selects Bit 31 of

the multicast hash table high register.

3.4.2.1 Hash Perfect Filtering

In hash perfect filtering, if the received frame is a physical address, the LAN9221/LAN9221i Packet

Filter block perfect-filters the incoming frame’s destination field with the value programmed into the

MAC Address High register and the MAC Address Low register. If the incoming frame is a multicast

frame, however, the LAN9221/LAN9221i packet filter function performs an imperfect address filtering

against the hash table.

The imperfect filtering against the hash table is the same imperfect filtering process described in the

“Hash Only Filtering” section above.

3.4.2.2 Inverse Filtering

In inverse filtering, the Packet Filter Block accepts incoming frames with a destination address not

matching the perfect address (i.e., the value programmed into the MAC Address High register and the

MAC Address Low register in the CRC block and rejects frames with destination addresses matching

the perfect address).

0 0 0 1 1 Hash Filtering for physical and

multicast addresses

0 0 1 0 0 Inverse Filtering

X 1 0 X X Promiscuous

1 0 0 0 X Pass all multicast frames. Frames

with physical addresses are

perfect-filtered

1 0 0 1 1 Pass all multicast frames. Frames

with physical addresses are hash-

filtered

Table 3.1 Address Filtering Modes (continued)

MCPAS PRMS INVFILT HO HPFILT DESCRIPTION

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For all filtering modes, when the MCPAS bit is set, all multicast frames are accepted. When the PRMS

bit is set, all frames are accepted regardless of their destination address. This includes all broadcast

frames as well.

3.5 Wake-up Frame Detection

Setting the Wake-Up Frame Enable bit (WUEN) in the “WUCSR—Wake-up Control and Status

normal data reception is disabled, and detection logic within the MAC examines receive data for the

pre-programmed wake-up frame patterns. The LAN9221/LAN9221i can be programmed to notify the

host of the wake-up frame detection with the assertion of the host interrupt (IRQ) or assertion of the

power management event signal (PME). Upon detection, the Wake-Up Frame Received bit (WUFR) in

the WUCSR is set. When the host clears the WUEN bit the LAN9221/LAN9221i will resume normal

receive operation.

Before putting the MAC into the wake-up frame detection state, the host must provide the detection

logic with a list of sample frames and their corresponding byte masks. This information is written into

the Wake-up Frame Filter register (WUFF). Please refer to Section 5.4.11, "WUFF—Wake-up Frame

Filter," on page 115 for additional information on this register.

The MAC supports four programmable filters that support many different receive packet patterns. If

remote wake-up mode is enabled, the remote wake-up function receives all frames addressed to the

MAC. It then checks each frame against the enabled filter and recognizes the frame as a remote wake-

up frame if it passes the wakeup frame filter register’s address filtering and CRC value match.

In order to determine which bytes of the frames should be checked by the CRC module, the MAC uses

a programmable byte mask and a programmable pattern offset for each of the four supported filters.

The pattern’s offset defines the location of the first byte that should be checked in the frame. Since

the destination address is checked by the address filtering Function, the pattern offset is always greater

than 12.

The byte mask is a 31-bit field that specifies whether or not each of the 31 contiguous bytes within

the frame, beginning in the pattern offset, should be checked. If bit j in the byte mask is set, the

detection logic checks byte offset +j in the frame. In order to load the Wake-up Frame Filter register,

the host LAN driver software must perform eight writes to the Wake-up Frame Filter register (WUFF).

The Diagram shown in Table 3.2, "Wake-Up Frame Filter Register Structure" below, shows the wake-

up frame filter register’s structure.

Note 3.1 Wake-up frame detection can be performed when the LAN9221/LAN9221i is in the D0 or

D1 power states. In the D0 state, wake-up frame detection is enabled when the WUEN bit

is set.

Note 3.2 Wake-up frame detection, as well as Magic Packet detection, is always enabled and

cannot be disabled when the device enters the D1 state.

Note 3.3 When wake-up frame detection is enabled via the WUEN bit of the WUCSR—Wake-up

Control and Status Register, a broadcast wake-up frame will wake-up the device despite

the state of the Disable Broadcast Frame (BCAST) bit in the MAC_CR—MAC Control

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The Filter i Byte Mask defines which incoming frame bytes Filter i will examine to determine whether

or not this is a wake-up frame. Tab l e 3 . 3 , describes the byte mask’s bit fields.

The Filter i command register controls Filter i operation. Table 3.4 shows the Filter I command register.

The Filter i Offset register defines the offset in the frame’s destination address field from which the

frames are examined by Filter i. Table 3. 5 describes the Filter i Offset bit fields.

Table 3.2 Wake-Up Frame Filter Register Structure

Filter 0 Byte Mask

Filter 1 Byte Mask

Filter 2 Byte Mask

Filter 3 Byte Mask

Reserved Filter 3

Command

Reserved Filter 2

Command

Reserved Filter 1

Command

Reserved Filter 0

Command

Filter 3 Offset Filter 2 Offset Filter 1Offset Filter 0 Offset

Filter 1 CRC-16 Filter 0 CRC-16

Filter 3 CRC-16 Filter 2 CRC-16

Table 3.3 Filter i Byte Mask Bit Definitions

FILTER I BYTE MASK DESCRIPTION

FIELD DESCRIPTION

31 Must be zero (0)

30:0 Byte Mask: If bit j of the byte mask is set, the CRC machine processes byte number pattern - (offset

+ j) of the incoming frame. Otherwise, byte pattern - (offset + j) is ignored.

Table 3.4 Filter i Command Bit Definitions

FILTER i COMMANDS

FIELD DESCRIPTION

3Address Type: Defines the destination address type of the pattern. When bit is set, the pattern

applies

only to multicast frames. When bit is cleared, the pattern applies only to unicast frames.

2:1 RESERVED

0Enable Filter: When bit is set, Filter i is enabled, otherwise, Filter i is disabled.

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The Filter i CRC-16 register contains the CRC-16 result of the frame that should pass Filter i.

Table 3.6 describes the Filter i CRC-16 bit fields.

3.5.1 Magic Packet Detection

Setting the Magic Packet Enable bit (MPEN) in the “WUCSR—Wake-up Control and Status Register”,

places the LAN9221/LAN9221i MAC in the “Magic Packet” detection mode. In this mode, normal data

reception is disabled, and detection logic within the MAC examines receive data for a Magic Packet.

The LAN9221/LAN9221i can be programmed to notify the host of the “Magic Packet” detection with

the assertion of the host interrupt (IRQ) or assertion of the power management event signal (PME).

Upon detection, the Magic Packet Received bit (MPR) in the WUCSR is set. When the host clears the

MPEN bit the LAN9221/LAN9221i will resume normal receive operation. Please refer to Section 5.4.12,

"WUCSR—Wake-up Control and Status Register," on page 115 for additional information on this

In Magic Packet mode, the Power Management Logic constantly monitors each frame addressed to

the node for a specific Magic Packet pattern. It checks only packets with the MAC’s address or a

broadcast address to meet the Magic Packet requirement. The Power Management Logic checks each

received frame for the pattern 48h FF_FF_FF_FF_FF_FF after the destination and source address

field.

Then the Function looks in the frame for 16 repetitions of the MAC address without any breaks or

interruptions. In case of a break in the 16 address repetitions, the PMT Function scans for the

48'hFF_FF_FF_FF_FF_FF pattern again in the incoming frame.

The 16 repetitions may be anywhere in the frame but must be preceded by the synchronization stream.

The device will also accept a multicast frame, as long as it detects the 16 duplications of the MAC

address. If the MAC address of a node is 00h 11h 22h 33h 44h 55h, then the MAC scans for the

following data sequence in an Ethernet: Frame.

Table 3.5 Filter i Offset Bit Definitions

FILTER I OFFSET DESCRIPTION

FIELD DESCRIPTION

7:0 Pattern Offset: The offset of the first byte in the frame on which CRC is checked for wake-up frame

recognition. The minimum value of this field must be 12 since there should be no CRC check for

the destination address and the source address fields. The MAC checks the first offset byte of the

frame for CRC and checks to determine whether the frame is a wake-up frame. Offset 0 is the first

byte of the incoming frame's destination address.

Table 3.6 Filter i CRC-16 Bit Definitions

FILTER I CRC-16 DESCRIPTION

FIELD DESCRIPTION

15:0 Pattern CRC-16: This field contains the 16-bit CRC value from the pattern and the byte mask

programmed to the wake-up filter register Function. This value is compared against the CRC

calculated on the incoming frame, and a match indicates the reception of a wakeup frame.

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Destination Address Source Address ……………FF FF FF FF FF FF

00 11 22 33 44 55 00 11 22 33 44 55 00 11 22 33 44 55 00 11 22 33 44 55

…CRC

It should be noted that Magic Packet detection can be performed when LAN9221/LAN9221i is in the

D0 or D1 power states. In the D0 state, “Magic Packet” detection is enabled when the MPEN bit is

set. In the D1 state, Magic Packet detection, as well as wake-up frame detection, are automatically

enabled when the device enters the D1 state.

3.6 Checksum Offload Engines (COE)

The LAN9221/LAN9221i contains two checksum offload engines, which offload the calculation of the

16-bit checksum for transmitted and received Ethernet frames. The functionality of the checksum

offload engines is described in the following sections:

Receive Checksum Offload Engine (RXCOE)

Transmit Checksum Offload Engine (TXCOE)

3.6.1 Receive Checksum Offload Engine (RXCOE)

The receive checksum offload engine provides assistance to the CPU by calculating a 16-bit checksum

for a received Ethernet frame. The RXCOE readily supports the following IEEE802.3 frame formats:

Type II Ethernet frames

SNAP encapsulated frames

Support for up to 2, 802.1q VLAN tags

The resulting checksum value can also be modified by software to support other frame formats.

The RXCOE has two modes of operation. In mode 0, the RXCOE calculates the checksum between

the first 14 bytes of the Ethernet frame and the FCS. This is illustrated in Figure 3.2.

In mode 1, the RXCOE supports VLAN tags and a SNAP header. In this mode the RXCOE calculates

the checksum at the start of L3 packet. The VLAN1 tag register is used by the RXCOE to indicate

what protocol type is to be used to indicate the existence of a VLAN tag. This value is typically 8100h.

Figure 3.2 RXCOE Checksum Calculation

DST SRC

Frame Data

Calculate Checksum

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Example frame configurations:

Figure 3.3 Type II Ethernet Frame

Figure 3.4 Ethernet Frame with VLAN Tag

Figure 3.5 Ethernet Frame with Length Field and SNAP Header

DST SRC

0123

L3 Packet

Calculate Checksum

1DWORD

DST SRC

0 1 2 3

L3 Packet

Calculate Checksum

1DWORD

DST SRC L3 Packet

012

{DSAP, SSAP, CTRL, OUI[23:16]} {OUI[15:0], PID[15:0]}

345

Calculate Checksum

1DWORD

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The RXCOE supports a maximum of two VLAN tags. If there are more than two VLAN tags, the VLAN

protocol identifier for the third tag is treated as an Ethernet type field. The checksum calculation will

begin immediately after the type field.

The RXCOE resides in the RX path within the MAC. As the RXCOE receives an Ethernet frame it

calculates the 16-bit checksum. The RXCOE passes the Ethernet frame to the RX Data FIFO with the

checksum appended to the end of the frame. The RXCOE inserts the checksum immediately after the

last byte of the Ethernet frame. The packet length field in the RX status word (refer to Section 3.13.3)

will indicate that the frame size has increased by two bytes to accommodate the checksum.

Setting the RXCOE_EN bit in the COE_CR—Checksum Offload Engine Control Register enables the

RXCOE, while the RXCOE_MODE bit selects the operating mode. When the RXCOE is disabled, the

the received data is simply passed through the RXCOE unmodified.

Note: Software applications must stop the receiver and flush the RX data path before changing the

state of the RXCOE_EN or RXCOE_MODE bits.

Note: When the RXCOE is enabled, automatic pad stripping must be disabled (bit 8 (PADSTR) of

the MAC_CR—MAC Control Register) and vice versa. These functions cannot be enabled

simultaneously.

Figure 3.6 Ethernet Frame with VLAN Tag and SNAP Header

Figure 3.7 Ethernet Frame with Multiple VLAN Tags and SNAP Header

DST SRC

L3 Packet

0 1 2

{DSAP, SSAP, CTRL,

OUI[23:16]} {OUI[15:0], PID[15:0]}

4 5 6

Calculate Checksum

1DWORD

DST SRC

L3 Packet

0 1 2

{DSAP, SSAP, CTRL,

OUI[23:16]} {OUI[15:0], PID[15:0]}

6 7 8

Calculate Checksum

1DWORD

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3.6.1.1 RX Checksum Calculation

The checksum is calculated 16 bits at a time. In the case of an odd sized frame, an extra byte of zero

is used to pad up to 16 bits.

Consider the following packet: DA, SA, Type, B0, B1, B2 … BN, FCS

Let [A, B] = A*256 + B;

If the packet has an even number of octets then

checksum = [B1, B0] + C0 + [B3, B2] + C1 + … + [BN, BN-1] + CN-1

Where C0, C1, ... CN-1 are the carry out results of the intermediate sums.

If the packet has an odd number of octets then

checksum = [B1, B0] + C0 + [B3, B2] + C1 + … + [0, BN] + CN-1

3.6.2 Transmit Checksum Offload Engine (TXCOE)

The transmit checksum offload engine provides assistance to the CPU by calculating a 16-bit

checksum, typically for TCP, for a transmit Ethernet frame. The TXCOE calculates the checksum and

inserts the results back into the data stream as it is transferred to the MAC.

To activate the TXCOE and perform a checksum calculation, the host must first set the TX checksum

offload engine enable bit (TXCOE_EN) in the COE_CR—Checksum Offload Engine Control Register.

The host then pre-pends a 3 DWORD buffer to the data that will be transmitted. The pre-pended buffer

includes a TX Command ‘A’, TX Command ‘B’, and a 32-bit TX checksum preamble. When bit 14 (CK)

of the TX Command ‘B’ is set in conjunction with bit 13 (FS) of TX Command ‘A’ and bit 16

(TXCOE_EN) of the COE_CR register, the TXCOE will perform a checksum calculation on the

associated packet. When these three bits are set, a 32-bit TX checksum preamble must be pre-pended

to the beginning of the TX packet (refer to Table 3.7). The TX checksum preamble instructs the TXCOE

on the handling of the associated packet. Bits 11:0 of the TX checksum preamble define the byte offset

at which the data checksum calculation will begin (TXCSSP). The checksum calculation will begin at

this offset and will continue until the end of the packet. The data checksum calculation must not begin

in the MAC header (first 14 bytes) or in the last 4 bytes of the TX packet. When the calculation is

complete, the checksum will be inserted into the packet at the byte offset defined by bits 27:16 of the

TX checksum preamble (TXCSLOC). The TX checksum cannot be inserted in the MAC header (first

14 bytes) or in the last 4 bytes of the TX packet. If the CK bit is not set in the first TX Command ‘B’

of a packet, the packet is passed directly through the TXCOE without modification, regardless if the

TXCOE_EN is set. An example of a TX packet with a pre-pended TX checksum preamble can be

found in Section 3.12.6.3, "TX Example 3". In this example the host writes the packet data to the

ethernet controller in four fragments, the first containing the TX Checksum Preamble. Figure 3.23

shows how these fragments are loaded into the TX Data FIFO. For more information on the TX

Command ‘A’ and TX Command ‘B’, refer to Section 3.12.2, "TX Command Format".

If the TX packet already includes a partial checksum calculation (perhaps inserted by an upper layer

protocol), this checksum can be included in the hardware checksum calculation by setting the TXCSSP

field in the TX checksum preamble to include the partial checksum. The partial checksum can be

replaced by the completed checksum calculation by setting the TXCSLOC pointer to point to the

location of the partial checksum.

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Note: When the TXCOE is enabled, the third DWORD of the pre-pended packet is not transmitted.

However, 4 bytes must be added to the packet length field in TX Command ‘B’.

Note: The TX checksum preamble must be DWORD-aligned (i.e., the two least significant bits of the

Data Start Offset fields in TX Command “A” must be zero). Any valid buffer end alignment

setting can be used.

Note: Software applications must stop the transmitter and flush the TX data path before changing the

state of the TXCOE_EN bit. However, the CK bit of TX Command ‘B’ can be set or cleared on

a per-packet basis.

3.6.2.1 TX Checksum Calculation

The TX checksum calculation is performed using the same operation as the RX checksum shown in

Section 3.6.1.1, with the exception that the calculation starts as indicated by the preamble, and the

transmitted checksum is the one’s-compliment of the final calculation.

Note: When the TX checksum offload feature is invoked, if the calculated checksum is 0000h, it is

left unaltered. UDP checksums are optional under IPv4, and a zero checksum calculated by

the TX checksum offload feature will erroneously indicate to the receiver that no checksum was

calculated, however, the packet will typically not be rejected by the receiver. Under IPv6,

however, according to RFC 2460, the UDP checksum is not optional. A calculated checksum

that yields a result of zero must be changed to FFFFh for insertion into the UDP header. IPv6

receivers discard UDP packets containing a zero checksum. Thus, this feature must not be

used for UDP checksum calculation under IPv6.

3.7 Host Bus Operations

3.7.1 Bus Writes

The host processor is required to perform two contiguous 16-bit writes to complete a single DWORD

transfer. This DWORD must begin and end on a DWORD address boundary (A[2] and higher, cannot

change during a sixteen bit write). No ordering requirements exist. The processor can access either

the low or high word first, as long as the next write is performed to the other word. If a write to the

same word is performed, the LAN9221/LAN9221i disregards the transfer.

Table 3.7 TX Checksum Preamble

FIELD DESCRIPTION

31:28 RESERVED

27:16 TXCSLOC - TX Checksum Location

This field specifies the byte offset where the TX checksum will be inserted in the TX packet. The

checksum will replace two bytes of data starting at this offset.

Note: The TX checksum cannot be inserted in the MAC header (first 14 bytes) or in the last 4

bytes of the TX packet.

15:12 RESERVED

11:0 TXCSSP - TX Checksum Start Pointer

This field indicates start offset, in bytes, where the checksum calculation will begin in the associated

TX packet.

Note: The data checksum calculation must not begin in the MAC header (first 14 bytes) or in

the last 4 bytes of the TX packet.

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3.7.2 Bus Reads

The host processor is required to perform two consecutive 16-bit reads to complete a single DWORD

transfer. This DWORD must begin and end on a DWORD address boundary (A[2] and higher, cannot

change during a sixteen bit read). 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 data read is invalid and should be re-read. This is not a fatal error. The

LAN9221/LAN9221i will reset its read counters and restart a new cycle on the next read.

3.7.3 Mixed Endian Support

In order to allow flexibility with a range of designs, the LAN9221/LAN9221i supports mixed endian Data

FIFO accesses. The LAN9221/LAN9221i provides the ability to select Data FIFO endianess separately

for accesses through the Data FIFO ports (addresses 00h-3Ch) or using the FIFO_SEL input signal.

This is accomplished via the FPORTEND and FSELEND bits of the HW_CFG—Hardware

Configuration Register, respectively.

The FPORTEND bit determines the endianess of RX and TX Data FIFO host accesses made through

the Data FIFO port addresses (00h-3Ch). When FPORTEND is cleared, Data FIFO port accesses

utilize little endian byte ordering. When FPORTEND is set, Data FIFO port accesses utilize big endian

byte ordering.

The FSELEND bit determines the endianess of RX and TX Data FIFO host accesses when using the

FIFO_SEL signal. When FSELEND is cleared, FIFO_SEL accesses utilize little endian byte ordering.

When FSELEND is set, FIFO_SEL accesses utilize big endian byte ordering.

In addition to mixed endian support, the LAN9221/LAN9221i provides a word swap function, as

described in Section 3.7.4. The word swap function combined with the endianess select bits described

above determines how the Data/Status FIFO’s and CSR host access byte ordering is applied. Tabl e 3 . 8

describes the various operation modes of the endianess and word swap ordering logic. Figure 3.9

illustrates the FIFO access byte ordering under various endianess and word swap settings. Refer to

Section 3.7.4 for additional details.

Note: CSR and status FIFO accesses are not affected by the FPORTEND and FSELEND endianess

select bits.

3.7.4 Word Swap Function

In addition to mixed endian functionality, the LAN9221/LAN9221i supports a Word Swap Function. This

feature is controlled by the Word Swap Register, which is described in Section 5.3.17,

"WORD_SWAP—Word Swap Control," on page 97. This register affects how words on the data bus

are written to or read from the Control and Status Registers and the Transmit and Receive Data/Status

FIFOs.

Both the word swap function and the mixed endian control bits contain the ability to change the byte

ordering of host data path accesses. Figure 3.8 illustrates the order in which the word swap and

endianess select logic is applied within the LAN9221/LAN9221i. Logically, the endian control logic is

applied after the word swap logic for write operations, and before the word swap logic for read

operations.

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Data path operations for the various supported endianess and word swap configurations are illustrated

in Figure 3.9. Table 3.8, "Endian Ordering Logic Operation" illustrates the byte ordering applied by the

endian logic for each type of host access. This figure and table assume an internal byte ordering of 3-

2-1-0, where ‘3’ is the most significant byte (data[31:24]) and ‘0’ is the least significant byte (data[7:0]).

Figure 3.8 LAN9221/LAN9221i Host Data Path Diagram

"WORD SWAP"

Logic

FIFO Port Endian Ordering

Logic

RX/TX Data FIFO Port

Access (addresses 00h to

3Ch)

Direct FIFO Access Endian

Ordering Logic

RX/TX Data FIFO Direct

Access

(FIFO_SEL = 1)

CSRs and Status FIFOs

FPORTEND

(HW_CFG[29])

FSELEND

(HW_CFG[28])

D[15:0]

(Host Data Bus)

WORD_SWAP

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Figure 3.9 FIFO Access Byte Ordering

BIG ENDIAN

(FPORTEND = 1 for Data FIFO port access on addresses 00h-3Ch)

AND/OR (FSELEND = 1 for Data FIFO direct access when FIFO_SEL=1)

0123

078151623

31 24

07815

A[1] = 0

A[1] = 1

MSB LSB

HOST DATA BUS

INTERNAL FIFO ORDER

0123

07815

078151623

31 24

A[1] = 0

A[1] = 1

MSB LSB

HOST DATA BUS

INTERNAL FIFO ORDER

WORD_SWAP != FFFF_FFFFh

LITTLE ENDIAN

(FPORTEND = 0 for Data FIFO port access on addresses 00h-3Ch)

AND/OR (FSELEND = 0 for Data FIFO direct access when FIFO_SEL=1)

BIG ENDIAN

(FPORTEND = 1 for Data FIFO port access on addresses 00h-3Ch)

AND/OR (FSELEND = 1 for Data FIFO direct access when FIFO_SEL=1)

0123

078151623

31 24

07815

A[1] = 0

A[1] = 1

MSB LSB

HOST DATA BUS

INTERNAL FIFO ORDER

0123

07815

078151623

31 24

A[1] = 0

A[1] = 1

MSB LSB

HOST DATA BUS

INTERNAL FIFO ORDER

WORD_SWAP = FFFF_FFFFh

LITTLE ENDIAN

(FPORTEND = 0 for Data FIFO port access on addresses 00h-3Ch)

AND/OR (FSELEND = 0 for Data FIFO direct access when FIFO_SEL=1)

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3.8 General Purpose Timer (GP Timer)

The General Purpose Timer is a programmable block that can be used to generate periodic host

interrupts. The resolution of this timer is 100uS.

The GP Timer loads the GPT_CNT Register with the value in the GPT_LOAD field and begins counting

down when the TIMER_EN bit is set to a ‘1.’ On a reset, or when the TIMER_EN bit changes from

set ‘1’ to cleared ‘0,’ the GPT_LOAD field is initialized to FFFFh. The GPT_CNT register is also

initialized to FFFFh on a reset. Software can write the pre-load value into the GPT_LOAD field at any

time; e.g., before or after the TIMER_EN bit is asserted. The GPT Enable bit TIMER_EN is located in

the GPT_CFG register.

Once enabled, the GPT counts down either until it reaches 0000h or until a new pre-load value is

written to the GPT_LOAD field. At 0000h, the counter wraps around to FFFFh, asserts the GPT

interrupt status bit and the IRQ signal if the GPT_INT_EN bit is set, and continues counting. The GPT

interrupt status bit is in the INT_STS Register. The GPT_INT hardware interrupt can only be set if the

GPT_INT_EN bit is set. GPT_INT is a sticky bit (R/WC); i.e., once the GPT_INT bit is set, it can only

be cleared by writing a ‘1’ to the bit.

Table 3.8 Endian Ordering Logic Operation

FIFO Access via Data

FIFO Port (00h-3Ch)

Direct FIFO Access via

FIFO_SEL CSR Access

Host Data Bus Host Data Bus Host Data Bus

D[15:8] D[7:0] D[15:8] D[7:0] D[15:8] D[7:0]

WORD_SWAP != FFFF_FFFFh

FPORTEND=0

FSELEND=0

A1=1 323232

A1=0 101010

FPORTEND=1

FSELEND=0

A1=1 013232

A1=0 231010

FPORTEND=0

FSELEND=1

A1=1 320132

A1=0 102310

FPORTEND=1

FSELEND=1

A1=1 010 132

A1=0 232 310

WORD_SWAP = FFFF_FFFFh

FPORTEND=0

FSELEND=0

A1=1 101010

A1=0 323232

FPORTEND=1

FSELEND=0

A1=1 231010

A1=0 013232

PORTEND=0

FSELEND=1

A1=1 102310

A1=0 320132

PORTEND=1

FSELEND=1

A1=1 232 310

A1=0 010 132

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3.9 EEPROM Interface

The LAN9221/LAN9221i can optionally load its MAC address from an external serial EEPROM. If a

properly configured EEPROM is detected by the LAN9221/LAN9221i at power-up, hard reset or soft

reset, the ADDRH and ADDRL registers will be loaded with the contents of the EEPROM. If a properly

configured EEPROM is not detected, it is the responsibility of the host LAN Driver to set the IEEE

addresses.

The LAN9221/LAN9221i EEPROM controller also allows the host system to read, write and erase the

contents of the Serial EEPROM. The EEPROM controller supports most “93C46” type EEPROMs

configured for 128 x 8-bit operation.

3.9.1 MAC Address Auto-Load

On power-up, hard reset or soft reset, the EEPROM controller attempts to read the first byte of data

from the EEPROM (address 00h). If the value A5h is read from the first address, then the EEPROM

controller will assume that an external Serial EEPROM is present. The EEPROM controller will then

access the next EEPROM byte and send it to the MAC Address register byte 0 (ADDRL[7:0]). This

process will be repeated for the next five bytes of the MAC Address, thus fully programming the 48-

bit MAC address. Once all six bytes have been programmed, the “MAC Address Loaded” bit is set in

the E2P_CMD register. A detailed explanation of the EEPROM byte ordering with respect to the MAC

address is given in Section 5.4.3, "ADDRL—MAC Address Low Register," on page 110.

If an 0xA5h is not read from the first address, the EEPROM controller will end initialization. It is then

the responsibility of the host LAN driver software to set the IEEE address by writing to the MAC’s

ADDRH and ADDRL registers.

The host can initiate a reload of the MAC address from the EEPROM by issuing the RELOAD

command via the E2P command (E2P_CMD) register. If the first byte read from the EEPROM is not

A5h, it is assumed that the EEPROM is not present, or not programmed, and the MAC address reload

will fail. The “MAC Address Loaded” bit indicates a successful reload of the MAC address.

3.9.2 EEPROM Host Operations

After the EEPROM controller has finished reading (or attempting to read) the MAC after power-on, hard

reset or soft reset, the host is free to perform other EEPROM operations. EEPROM operations are

performed using the E2P_CMD and E2P data (E2P_DATA) registers. Section 5.3.23, "E2P_CMD –

EEPROM Command Register," on page 102 provides an explanation of the supported EEPROM

operations.

If the EEPROM operation is the “write location” (WRITE) or “write all” (WRAL) commands, the host

must first write the desired data into the E2P_DATA register. The host must then issue the WRITE or

WRAL command using the E2P_CMD register by setting the EPC_CMD field appropriately. If the

operation is a WRITE, the EPC_ADDR field in E2P_CMD must also be set to the desired location. The

command is executed when the host sets the EPC_BSY bit high. The completion of the operation is

indicated when the EPC_BSY bit is cleared.

If the EEPROM operation is the “read location” (READ) operation, the host must issue the READ

command using the E2P_CMD with the EPC_ADDR set to the desired location. The command is

executed when the host sets the EPC_BSY bit high. The completion of the operation is indicated when

the EPC_BSY bit is cleared, at which time the data from the EEPROM may be read from the

E2P_DATA register.

Other EEPROM operations are performed by writing the appropriate command to the EPC_CMD

operation is indicated when the EPC_BSY bit is cleared. In all cases the host must wait for EPC_BSY

to clear before modifying the E2P_CMD register.

Note: The EEPROM device powers-up in the erase/write disabled state. To modify the contents of

the EEPROM the host must first issue the EWEN command.

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If an operation is attempted, and an EEPROM device does not respond within 30mS, the

LAN9221/LAN9221i will timeout, and the EPC timeout bit (EPC_TO) in the E2P_CMD register will be

set.

Figure 3.10, "EEPROM Access Flow Diagram" illustrates the host accesses required to perform an

EEPROM Read or Write operation.

The host can disable the EEPROM interface through the GPIO_CFG register. When the interface is

disabled, the EEDIO and ECLK signals can be used as general-purpose outputs, or they may be used

to monitor internal MII signals.

3.9.2.1 Supported EEPROM Operations

The EEPROM controller supports the following EEPROM operations under host control via the

E2P_CMD register. The operations are commonly supported by “93C46” EEPROM devices. A

description and functional timing diagram is provided below for each operation. Please refer to the

E2P_CMD register description in Section 5.3.23, "E2P_CMD – EEPROM Command Register," on

page 102 for E2P_CMD field settings for each command.

Figure 3.10 EEPROM Access Flow Diagram

Id le

Write Data

Write

Command

Read

Command

Busy Bit = 0

Id le

Write

Command

Reg is te r

Read

Command

Reg is te r

Read Data

Reg is te r

Busy Bit = 0

EEPROM Write EEPROM Read

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ERASE (Erase Location): If erase/write operations are enabled in the EEPROM, this command will

erase the location selected by the EPC Address field (EPC_ADDR). The EPC_TO bit is set if the

EEPROM does not respond within 30ms.

Figure 3.11 EEPROM ERASE Cycle

ERAL (Erase All): If erase/write operations are enabled in the EEPROM, this command will initiate a

bulk erase of the entire EEPROM.The EPC_TO bit is set if the EEPROM does not respond within

30ms.

Figure 3.12 EEPROM ERAL Cycle

EECLK

EEDIO (INPUT)

EEDIO (OUTPUT)

EECS

11A6 A0

tCSL

EECLK

EEDIO (INPUT)

EEDIO (OUTPUT)

EECS

1010

tCSL

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EWDS (Erase/Write Disable): After issued, the EEPROM will ignore erase and write commands. To

re-enable erase/write operations issue the EWEN command.

Figure 3.13 EEPROM EWDS Cycle

EWEN (Erase/Write Enable): Enables the EEPROM for erase and write operations. The EEPROM

will allow erase and write operations until the “Erase/Write Disable” command is sent, or until power

is cycled.

Note: The EEPROM device will power-up in the erase/write-disabled state. Any erase or write

operations will fail until an Erase/Write Enable command is issued.

Figure 3.14 EEPROM EWEN Cycle

EECLK

EEDIO (INPUT)

EEDIO (OUTPUT)

EECS

1000

tCSL

EECLK

EEDIO (INPUT)

EEDIO (OUTPUT)

EECS

1011

tCSL

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READ (Read Location): This command will cause a read of the EEPROM location pointed to by EPC

Address (EPC_ADDR). The result of the read is available in the E2P_DATA register.

Figure 3.15 EEPROM READ Cycle

WRITE (Write Location): If erase/write operations are enabled in the EEPROM, this command will

cause the contents of the E2P_DATA register to be written to the EEPROM location selected by the

EPC Address field (EPC_ADDR). The EPC_TO bit is set if the EEPROM does not respond within

30ms.

Figure 3.16 EEPROM WRITE Cycle

WRAL (Write All): If erase/write operations are enabled in the EEPROM, this command will cause the

contents of the E2P_DATA register to be written to every EEPROM memory location. The EPC_TO bit

is set if the EEPROM does not respond within 30ms.

Figure 3.17 EEPROM WRAL Cycle

110A6

EECS

EECLK

EEDIO (OUTPUT) A0

D7 D0

EEDIO (INPUT)

tCSL

EECLK

EEDIO (INPUT)

EEDIO (OUTPUT)

EECS

11A6 A0 D7 D0

tCSL

EECLK

EEDIO (INPUT)

EEDIO (OUTPUT)

EECS

1D7 D0

001

tCSL

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Table 3.9, "Required EECLK Cycles", shown below, shows the number of EECLK cycles required for

each EEPROM operation.

3.9.2.2 MAC Address Reload

The MAC address can be reloaded from the EEPROM via a host command to the E2P_CMD register.

If a value of 0xA5h is not found in the first address of the EEPROM, the EEPROM is assumed to be

un-programmed and MAC Address Reload operation will fail. The “MAC Address Loaded” bit indicates

a successful load of the MAC address. The EPC_LOAD bit is set after a successful reload of the MAC

address.

3.9.2.3 EEPROM Command and Data Registers

Refer to Section 5.3.23, "E2P_CMD – EEPROM Command Register," on page 102 and Section 5.3.24,

"E2P_DATA – EEPROM Data Register," on page 104 for a detailed description of these registers.

Supported EEPROM operations are described in these sections.

3.9.2.4 EEPROM Timing

Refer to Section 6.11, "EEPROM Timing," on page 138 for detailed EEPROM timing specifications.

3.10 Power Management

The LAN9221/LAN9221i supports power-down modes to allow applications to minimize power

consumption. The following sections describe these modes.

3.10.1 System Description

Power is reduced to various modules by disabling the clocks as outlined in Table 3.10, “Power

Management States,” on page 45. All configuration data is saved when in either of the two low power

states. Register contents are not affected unless specifically indicated in the register description.

3.10.2 Functional Description

There is one normal operating power state, D0 and there are two power saving states: D1, and D2.

Upon entry into either of the two power saving states, only the PMT_CTRL register is accessible for

read operations. In either of the power saving states the READY bit in the PMT_CTRL register will be

cleared. Reads of any other addresses are forbidden until the READY bit is set. All writes, with the

exception of the wakeup write to BYTE_TEST, are also forbidden until the READY bit is set. Only when

in the D0 (Normal) state, when the READY bit is set, can the rest of the device be accessed.

Table 3.9 Required EECLK Cycles

OPERATION REQUIRED EECLK CYCLES

ERASE 10

ERAL 10

EWDS 10

EWEN 10

WRITE 18

WRAL 18

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Note 3.4 The LAN9221/LAN9221i must always be read at least once after power-up, reset, or upon

return from a power-saving state, otherwise write operations will not function.

In system configurations where the PME signal is shared amongst multiple devices, the WUPS field

within the PMT_CTRL register can be read to determine which LAN9221/LAN9221i device is driving

the PME signal.

When the LAN9221/LAN9221i is in a power saving state (D1 or D2), a write cycle to the BYTE_TEST

System Components,” on page 141 and Table 7.2, “Power Consumption Device and System

Components,” on page 141, shows the power consumption values for each power state.

Note 3.5 When the LAN9221/LAN9221i is in a power saving state, a write of any data to the

BYTE_TEST register will wake-up the device. DO NOT PERFORM WRITES TO OTHER

ADDRRESSES while the READY bit in the PMT_CTRL register is cleared.

3.10.2.1 D1 Sleep

Power consumption is reduced in this state by disabling clocks to portions of the internal logic as

shown in Table 3.10. In this mode the clock to the internal PHY and portions of the MAC are still

operational. This state is entered when the host writes a '01' to the PM_MODE bits in the Power

Management (PMT_CTRL) register. The READY bit in PMT_CTRL is cleared when entering the D1

state.

Wake-up frame and Magic Packet detection are automatically enabled in the D1 state. If properly

enabled via the WOL_EN and PME_EN bits, the LAN9221/LAN9221i will assert the PME hardware

signal upon the detection of the wake-up frame or magic packet. The LAN9221/LAN9221i can also

assert the host interrupt (IRQ) on detection of a wake-up frame or magic packet. Upon detection, the

WUPS field in PMT_CTRL will be set to a 10b.

Note 3.6 The PME interrupt status bit (PME_INT) in the INT_STS register is set regardless of the

setting of PME_EN.

Note 3.7 Wake-up frame and Magic Packet detection is automatically enabled when entering the D1

state. For wake-up frame detection, the wake-up frame filter must be programmed before

entering the D1 state (see Section 3.5, "Wake-up Frame Detection," on page 26). If used,

the host interrupt and PME signal must be enabled prior to entering the D1 state.

A write to the BYTE_TEST register, regardless of whether a wake-up frame or Magic Packet was

detected, will return LAN9221/LAN9221i to the D0 state and will reset the PM_MODE field to the D0

state. As noted above, the host is required to check the READY bit and verify that it is set before

attempting any other reads or writes of the device.

Note 3.8 The host must only perform read accesses prior to the ready bit being set.

Once the READY bit is set, the LAN9221/LAN9221i is ready to resume normal operation. At this time

the WUPS field can be cleared.

3.10.2.2 D2 Sleep

In this state, as shown in Ta b l e 3 . 1 0 , all clocks to the MAC and host bus are disabled and the PHY is

placed in a reduced power state. To enter this state, the EDPWRDOWN bit in register 17 of the PHY

(Mode Control/Status register) must be set. This places the PHY in the Energy Detect mode. The

PM_MODE bits in the PMT_CTRL register must then be set to 10b. Upon setting the PM_MODE bits,

the LAN9221/LAN9221i will enter the D2 sleep state. The READY bit in PMT_CTRL is cleared when

entering the D2 state.

Note 3.9 If carrier is present when this state is entered detection will occur immediately.

If properly enabled via the ED_EN and PME_EN bits, the LAN9221/LAN9221i will assert the PME

hardware signal upon detection of a valid carrier. Upon detection, the WUPS field in PMT_CTRL will

be set to a 01b.

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Note 3.10 The PME interrupt status bit on the INT_STS register (PME_INT) is set regardless of the

setting of PME_EN.

A write to the BYTE_TEST register, regardless of whether a carrier was detected, will return the

LAN9221/LAN9221i to the D0 state and will reset the PM_MODE field to the D0 state. As noted above,

the host is required to check the READY bit and verify that it is set before attempting any other reads

or writes of the device. Before the LAN9221/LAN9221i is fully awake from this state the EDPWRDOWN

bit in register 17 of the PHY must be cleared in order to wake the PHY. Do not attempt to clear the

EDPWRDOWN bit until the READY bit is set. After clearing the EDPWRDOWN bit the

LAN9221/LAN9221i is ready to resume normal operation. At this time the WUPS field can be cleared.

Table 3.10 Power Management States

Device

BLOCK

(NORMAL OPERATION)

(WOL)

(ENERGY DETECT)

PHY Full ON Full ON Energy Detect Power-Down

MAC Power

Management

Full ON RX Power Mgmt. Block

OFF

MAC and Host

Interface

Full ON OFF OFF

Internal Clock Full ON Full ON OFF

KEY

CLOCK ON

BLOCK DISABLED – CLOCK ON

FULL OFF

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3.10.2.3 Power Management Event Indicators

Figure 3.18 is a simplified block diagram of the logic that controls the external PME, and internal

pme_interrupt signals. The pme_interrupt signal is used to set the PME_INT status bit in the INT_STS

The PME_INT status bit in INT_STS will remain set until the internal pme_interrupt signal is cleared

by clearing the WUPS bits, or by clearing the corresponding WOL_EN or ED_EN bit. After clearing the

internal pme_interrupt signal, the PME_INT status bit may be cleared by writing a ‘1’ to this bit in the

INT_STS register. It should be noted that the LAN9221/LAN9221i can generate a host interrupt

regardless of the state of the PME_EN bit, or the external PME signal.

The external PME signal can be setup for pulsed, or static operation. When the PME_IND bit in the

PMT_CTRL register is set to a ‘1’, the external PME signal will be driven active for 50ms upon

detection of a wake-up event. When the PME_IND bit is cleared, the PME signal will be driven

continuously upon detection of a wake-up event. The PME signal is deactivated by clearing the WUPS

bits, or by clearing the corresponding WOL_EN or ED_EN bit. The PME signal can also be deactivated

by clearing the PME_EN bit.

Figure 3.18 PME and PME_INT Signal Generation

3.10.3 Internal PHY Power-Down Modes

There are 2 power-down modes for the internal PHY:

3.10.3.1 General Power-Down

This power-down is controlled by register 0, bit 11. In this mode the internal PHY, except the

management interface, is powered-down and stays in that condition as long as Phy register bit 0.11 is

HIGH. When bit 0.11 is cleared, the PHY powers up and is automatically reset. Please refer to Section

5.5.1, "Basic Control Register," on page 118 for additional information on this register.

PME

ED_EN

WOL_EN

50ms

PME_EN

PME_IND

PME_POL

PME_TYPE

LOGIC

WUEN

MPEN

phy_int

WUPS

WUFR

MPR

Denotes a level-triggered "sticky" status bit

PME_INT_EN

PME_INT

IRQ_EN

IRQ

Other System

Interrupts

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3.10.3.2 Energy Detect Power-Down

This power-down mode is activated by setting the Phy register bit 17.13 to 1. Please refer to Section

5.5.8, "Mode Control/Status," on page 122 for additional information on this register. In this mode when

no energy is present on the line, the PHY is powered down, with the exception of the management

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

In this mode, when the ENERGYON signal is low, the PHY is powered-down, and nothing is

transmitted. When energy is received - link pulses or packets - the ENERGYON signal goes high, and

the PHY powers-up. It automatically resets itself into the state it had prior to power-down, and asserts

the INT7.1 bit of the register defined in Section 5.5.11, "Interrupt Source Flag," on page 125. If the

ENERGYON interrupt is enabled, this event will cause an interrupt to the host. The first and possibly

the second packet to activate ENERGYON may be lost. When 17.13 is low, energy detect power-down

is disabled.

3.11 Detailed Reset Description

The LAN9221/LAN9221i has four reset sources:

Hardware Reset Input Pin (nRESET)

Soft Reset (SRST)

PHY Soft Reset via PMT_CTRL bit 10 (PHY_RST)

PHY Soft Reset via PHY Basic Control Register (PHY REG 0.15)

Table 3.11 shows the effect of the various reset sources on the LAN9221/LAN9221i's circuitry.

Note: For proper operation, the LAN9221/LAN9221i must be reset on power-up via the hardware

reset input (nRESET) or soft reset (SRST). To accomplish this, nRESET should be asserted

for the minimum period of 30ms at power-up. Alternatively, a soft reset may be performed

following power-up by setting the SRST bit of the HW_CFG register once the READY bit in the

PMT_CTRL register has been set. Refer to Section 3.11.1, "Hardware Reset Input (nRESET)"

and Section 3.11.3, "Soft Reset (SRST)" for additional information.

Note 3.11 After any PHY reset, the application must wait until the “Link Status” bit in the PHY’s “Basic

Status Register” (PHY Reg. 1.2) is set before attempting to transmit or receive data.

Note 3.12 After a power-up, nRESET or SRST, the LAN9221/LAN9221i will automatically check for

the presence of an external EEPROM. After any of these resets the application must verify

that the EPC Busy Bit (E2P_CMD, bit 31) is cleared before attempting to access the

EEPROM, or change the function of the GPO/GPIO signals, or before modifying the

ADDRH or ADDRL registers in the MAC.

Note 3.13 HBI - “Host Bus Interface”, NASR - Not affected by software reset.

Table 3.11 Reset Sources and Affected Circuitry

RESET

SOURCE PLL

HBI

Note

3.13

NASR

REGISTERS

Note 3.13 MIL MAC

PHY

Note 3.11

EEPROM MAC

ADDR.

RELOAD

Note 3.12

CONFIG.

STRAPS

LATCHED

nRESET XX X X X X X X

SRST XXX X

PHY_RST X

PHY REG 0.15 X

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APPLICATION NOTE: Under normal conditions, the READY bit in PMT_CTRL will be set (high -”1”) after an internal

reset (22ms). If the software driver polls this bit and it is not set within 100ms, then an error

condition occurred.

3.11.1 Hardware Reset Input (nRESET)

A hardware reset will occur when the nRESET input signal is driven low. The READY bit in the

PMT_CTRL register can be read from the host interface, and will read back a ‘0’ until the hardware

reset is complete. Upon completion of the hardware reset, the READY bit in PMT_CTRL is set high.

After the “READY” bit is set, the LAN9221/LAN9221i can be configured via its control registers. The

nRESET signal is pulled-high internally by the LAN9221/LAN9221i and can be left unconnected if

unused. If used, nRESET must be driven low for a minimum period as defined in Section 6.10, "Reset

Timing," on page 137. If nRESET is unused, the device must be reset following power-up via a soft

reset (SRST).

APPLICATION NOTE: Under normal conditions, the READY bit in PMT_CTRL will be set (high -”1”) immediately. If

the software driver polls this bit and it is not set within 100ms, then an error condition

occurred.

3.11.2 Resume Reset Timing

After issuing a write to the BYTE_TEST register to wake the LAN9221/LAN9221i from a power-down

state, the READY bit in PMT_CTRL will assert (set High) within 2ms.

APPLICATION NOTE: Under normal conditions, the READY bit in PMT_CTRL will be set (high -”1”) within 2 ms. If

the software driver polls this bit and it is not set within 100ms, then an error condition

occurred.

3.11.3 Soft Reset (SRST)

Soft reset is initiated by writing a ‘1’ to bit 0 of the HW_CFG register (SRST). This self-clearing bit will

return to ‘0’ after approximately 2 μs, at which time the Soft Reset is complete. Soft reset does not

clear control register bits marked as NASR. Following power-on, a soft reset must not be performed

until the READY bit in the PMT_CTRL register has been set.

APPLICATION NOTE: Under normal conditions, the READY bit in PMT_CTRL will be set (high -”1”) immediately,

(within 2μs). If the software driver polls this bit and it is not set within 100ms, then an error

condition occurred.

3.11.4 PHY Reset Timing

The following sections specify the operation and time required for the internal PHY to become

operational after various resets or when returning from the reduced power state.

3.11.4.1 PHY Soft Reset via PMT_CTRL bit 10 (PHY_RST)

The PHY soft reset is initiated by writing a ‘1’ to bit 10 of the PMT_CTRL register (PHY_RST). This

self-clearing bit will return to ‘0’ after approximately 100 μs, at which time the PHY reset is complete.

3.11.4.2 PHY Soft Reset via PHY Basic Control Register (PHY Reg. 0.15)

The PHY Reg. 0.15 Soft Reset is initiated by writing a ‘1’ to bit 15 of the PHY’s Basic Control Register.

This self-clearing bit will return to ‘0’ at which time the PHY reset is complete.

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3.12 TX Data Path Operation

Data is queued for transmission by writing it into the TX data FIFO. Each packet to be transmitted may

be divided among multiple buffers. Each buffer starts with a two DWORD TX command (TX command

‘A’ and TX command ‘B’). The TX command instructs the LAN9221/LAN9221i on the handling of the

associated buffer. Packet boundaries are delineated using control bits within the TX command.

The host provides a 16-bit Packet Tag field in the TX command. The Packet Tag value is appended

to the corresponding TX status DWORD. All Packet Tag fields must have the same value for all buffers

in a given packet. If tags differ between buffers in the same packet the TXE error will be asserted. Any

value may be chosen for a Packet Tag as long as all tags in the same Packet are identical. Packet

Tags also provide a method of synchronization between transmitted packets and their associated

status. Software can use unique Packet Tags to assist with validating matching status completions.

Note 3.14 The use of packet tags is not required by the hardware. This is a software LAN driver only

application example for use of this field.

A Packet Length field in the TX command specifies the number of bytes in the associated packet. All

Packet Length fields must have the same value for all buffers in a given packet. Hardware compares

the Packet Length field and the actual amount of data received by the Ethernet controller. If the actual

packet length count does not match the Packet Length field as defined in the TX command, the

Transmitter Error (TXE) flag is asserted.

The LAN9221/LAN9221i can be programmed to start payload transmission of a buffer on a byte

boundary by setting the “Data Start Offset” field in the TX command. The “Data Start Offset” field points

to the actual start of the payload data within the first 8 DWORDs of the buffer. Data before the “Data

Start Offset” pointer will be ignored. When a packet is split into multiple buffers, each successive buffer

may begin on any arbitrary byte.

The LAN9221/LAN9221i can be programmed to strip padding from the end of a transmit packet in the

event that the end of the packet does not align with the host burst boundary. This feature is necessary

when the LAN9221/LAN9221i is operating in a system that always performs multi-word bursts. In such

cases the LAN9221/LAN9221i must guarantee that it can accept data in multiples of the Burst length

regardless of the actual packet length. When configured to do so, the LAN9221/LAN9221i will accept

extra data at the end of the packet and will remove the extra padding before transmitting the packet.

The LAN9221/LAN9221i automatically removes data up to the boundary specified in the Buffer End

Alignment field specified in each TX command.

The host can instruct the LAN9221/LAN9221i to issue an interrupt when the buffer has been fully

loaded into the TX FIFO contained in the LAN9221/LAN9221i and transmitted. This feature is enabled

through the TX command ‘Interrupt on Completion’ field.

Upon completion of transmission, irrespective of success or failure, the status of the transmission is

written to the TX status FIFO. TX status is available to the host and may be read using PIO operations.

An interrupt can be optionally enabled by the host to indicate the availability of a programmable

number TX status DWORDS.

Before writing the TX command and payload data to the TX FIFO, the host must check the available

TX FIFO space by performing a PIO read of the TX_FIFO_INF register. The host must ensure that it

does not overfill the TX FIFO or the TX Error (TXE) flag will be asserted.

The host proceeds to write the TX command by first writing TX command ‘A’, then TX command ‘B’.

After writing the command, the host can then move the payload data into the TX FIFO. TX status

DWORD’s are stored in the TX status FIFO to be read by the host at a later time upon completion of

the data transmission onto the wire.

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3.12.1 TX Buffer Format

TX buffers exist in the host’s memory in a given format. The host writes a TX command word into the

TX data buffer before moving the Ethernet packet data. The TX command A and command B are 32-

bit values that are used by the LAN9221/LAN9221i in the handling and processing of the associated

Ethernet packet data buffer. Buffer alignment, segmentation and other packet processing parameters

are included in the command structure. The following diagram illustrates the buffer format.

Figure 3.19 Simplified Host TX Flow Diagram

Idle

Check

available

FIFO

space

init

Write

Command

Write

Buffer

Last Buffer in

Packet

Not Last Buffer

Write

Start

Padding

(optional)

Read TX

Status

(optional)

TX Status

Available

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Figure 3.20, "TX Buffer Format", shows the TX Buffer as it is written into the LAN9221/LAN9221i. It

should be noted that not all of the data shown in this diagram is actually stored in the TX data FIFO.

This must be taken into account when calculating the actual TX data FIFO usage. Please refer to

Section 3.12.5, "Calculating Actual TX Data FIFO Usage," on page 55 for a detailed explanation on

calculating the actual TX data FIFO usage.

3.12.2 TX Command Format

The TX command instructs the TX FIFO controller on handling the subsequent buffer. The command

precedes the data to be transmitted. The TX command is divided into two, 32-bit words; TX command

‘A’ and TX command ‘B’.

There is a 16-bit packet tag in the TX command ‘B’ command word. Packet tags may, if host software

desires, be unique for each packet (i.e., an incrementing count). The value of the tag will be returned

in the RX status word for the associated packet. The Packet tag can be used by host software to

uniquely identify each status word as it is returned to the host.

Both TX command ‘A’ and TX command ‘B’ are required for each buffer in a given packet. TX

command ‘B’ must be identical for every buffer in a given packet. If the TX command ‘B’ words do not

match, the Ethernet controller will assert the Transmitter Error (TXE) flag.

Figure 3.20 TX Buffer Format

TX Command 'A'

Offset + Data DWORD0

Last Data & PAD

031

1st

2nd

3rd

Last

Host Write

Order

Optional Pad DWORD0

Optional Pad DWORDn

TX Command 'B'

Optional offset DWORD0

Optional offset DWORDn

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TX COMMAND ‘A’

Table 3.12 TX Command 'A' Format

BITS DESCRIPTION

31 Interrupt on Completion. When set, the TXDONE flag will be asserted when the current buffer has

been fully loaded into the TX FIFO. This flag may be optionally mapped to a host interrupt.

30:26 Reserved. These bits are reserved. Always write zeros to this field to guarantee future compatibility.

25:24 Buffer End Alignment. This field specifies the alignment that must be maintained on the last data

transfer of a buffer. The host will add extra DWORDs of data up to the alignment specified in the

table below. The LAN9221/LAN9221i will remove the extra DWORDs. This mechanism can be used

to maintain cache line alignment on host processors.

23:21 Reserved. These bits are reserved. Always write zeros to this field to guarantee future compatibility

20:16 Data Start Offset (bytes). This field specifies the offset of the first byte of TX data. The offset value

can be anywhere from 0 bytes to 31 a Byte offset.

15:14 Reserved. These bits are reserved. Always write zeros to this field to guarantee future compatibility

13 First Segment (FS). When set, this bit indicates that the associated buffer is the first segment of the

packet.

12 Last Segment. When set, this bit indicates that the associated buffer is the last segment of the

packet

11 Reserved. These bits are reserved. Always write zeros to this field to guarantee future compatibility.

10:0 Buffer Size (bytes). This field indicates the number of bytes contained in the buffer following this

command. This value, along with the Buffer End Alignment field, is read and checked by the

LAN9221/LAN9221i and used to determine how many extra DWORD’s were added to the end of the

Buffer. A running count is also maintained in the LAN9221/LAN9221i of the cumulative buffer sizes

for a given packet. This cumulative value is compared against the Packet Length field in the TX

command ‘B’ word and if they do not correlate, the TXE flag is set.

Note: The buffer size specified does not include the buffer end alignment padding or data start

offset added to a buffer.

[25] [24] End Alignment

0 0 4-byte alignment

0 1 16-byte alignment

1 0 32-byte alignment

11 Reserved

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TX COMMAND ‘B’

3.12.3 TX Data Format

The TX data section begins at the third DWORD in the TX buffer (after TX command ‘A’ and TX

command ‘B’). The location of the first byte of valid buffer data to be transmitted is specified in the

“Data Start Offset” field of the TX command ‘A’ word. Table 3.14, "TX DATA Start Offset", shows the

correlation between the setting of the LSB’s in the “Data Start Offset” field and the byte location of the

first valid data byte. Additionally, transmit buffer data can be offset by up to 7 additional DWORDS as

indicated by the upper three MSB’s (5:2) in the “Data Start Offset” field.

TX data is contiguous until the end of the buffer. The buffer may end on a byte boundary. Unused

bytes at the end of the packet will not be sent to the MIL for transmission.

The Buffer End Alignment field in TX command ‘A’ specifies the alignment that must be maintained for

the associated buffer. End alignment may be specified as 4-, 16-, or 32-byte. The host processor is

responsible for adding the additional data to the end of the buffer. The hardware will automatically

remove this extra data.

3.12.3.1 TX Buffer Fragmentation Rules

Transmit buffers must adhere to the following rules:

Each buffer can start and end on any arbitrary byte alignment

The first buffer of any transmit packet can be any length

Table 3.13 TX Command 'B' Format

BITS DESCRIPTION

31:16 Packet Tag. The host should write a unique packet identifier to this field. This identifier is added to

the corresponding TX status word and can be used by the host to correlate TX status words with

their corresponding packets.

Note: The use of packet tags is not required by the hardware. This field can be used by the LAN

software driver for any application. Packet Tags is one application example.

15 Reserved. This bit is reserved. Always write zeros to this bit to guarantee future compatibility.

14 TX Checksum Enable (CK). When this bit is set in conjunction with the first segment (FS) bit in TX

Command ‘A’ and the TX checksum offload engine enable bit (TXCOE_EN) in the

COE_CR—Checksum Offload Engine Control Register, the TX checksum offload engine (TXCOE)

will calculate a L3 checksum for the associated frame.

13 Add CRC Disable. When set, the automatic addition of the CRC is disabled.

12 Disable Ethernet Frame Padding. When set, this bit prevents the automatic addition of padding to

an Ethernet frame of less than 64 bytes. The CRC field is also added despite the state of the Add

CRC Disable field.

11 Reserved. These bits are reserved. Always write zeros to this field to guarantee future compatibility.

10:0 Packet Length (bytes). This field indicates the total number of bytes in the current packet. This

length does not include the offset or padding. If the Packet Length field does not match the actual

number of bytes in the packet the Transmitter Error (TXE) flag will be set.

Table 3.14 TX DATA Start Offset

Data Start Offset [1:0]: 11 10 01 00

First TX Data Byte: D[31:24] D[23:16] D[15:8] D[7:0]

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Middle buffers (i.e., those with First Segment = Last Segment = 0) must be greater than, or equal

to 4 bytes in length

The final buffer of any transmit packet can be any length

The MIL operates in store-and-forward mode and has specific rules with respect to fragmented

packets. The total space consumed in the TX FIFO (MIL) must be limited to no more than 2KB - 3

DWORDs (2,036 bytes total). Any transmit packet that is so highly fragmented that it takes more space

than this must be un-fragmented (by copying to a driver-supplied buffer) before the transmit packet

can be sent to the LAN9221/LAN9221i.

One approach to determine whether a packet is too fragmented is to calculate the actual amount of

space that it will consume, and check it against 2,036 bytes. Another approach is to check the number

of buffers against a worst-case limit of 86 (see explanation below).

3.12.3.2 Calculating Worst-Case TX FIFO (MIL) Usage

The actual space consumed by a buffer in the MIL TX FIFO consists only of any partial DWORD offsets

in the first/last DWORD of the buffer, plus all of the whole DWORDs in between. Any whole DWORD

offsets and/or alignments are stripped off before the buffer is loaded into the TX Data FIFO, and TX

command words are stripped off before the buffer is written to the MIL TX FIFO, so none of those

DWORDs count as space consumed. The worst-case overhead for a TX buffer is 6 bytes, which

assumes that it started on the high byte of a DWORD and ended on the low byte of a DWORD. A TX

packet consisting of 86 such fragments would have an overhead of 516 bytes (6 * 86) which, when

added to a 1514-byte max-size transmit packet (1516 bytes, rounded up to the next whole DWORD),

would give a total space consumption of 2,032 bytes, leaving 4 bytes to spare; this is the basis for the

"86 fragment" rule mentioned above.

3.12.4 TX Status Format

TX status is passed to the host CPU through a separate FIFO mechanism. A status word is returned

for each packet transmitted. Data transmission is suspended if the TX status FIFO becomes full. Data

transmission will resume when the host reads the TX status and there is room in the FIFO for more

“TX Status” data.

The host can optionally choose to not read the TX status. The host can optionally ignore the TX status

by setting the “TX Status Discard Allow Overrun Enable” (TXSAO) bit in the TX Configuration Register

(TX_CFG). If this option is chosen TX status will not be written to the FIFO. Setting this bit high allows

the transmitter to continue operation with a full TX status FIFO. In this mode the status information is

still available in the TX status FIFO, and TX status interrupts still function. In the case of an overrun,

the TXSUSED counter will stay at zero and no further TX status will be written to the TX status FIFO

until the host frees space by reading TX status. If TXSAO is enabled, a TXE error will not be generated

if the TX status FIFO overruns. In this mode the host is responsible for re-synchronizing TX status in

the case of an overrun.

BITS DESCRIPTION

31:16 Packet TAG. Unique identifier written by the host into the Packet Tag field of the TX command ‘B’

word. This field can be used by the host to correlate TX status words with the associated TX packets.

15 Error Status (ES). When set, this bit indicates that the Ethernet controller has reported an error. This

bit is the logical OR of bits 11, 10, 9, 8, 2, 1 in this status word.

14:12 Reserved. These bits are reserved. Always write zeros to this field to guarantee future compatibility.

11 Loss of Carrier. When set, this bit indicates the loss of carrier during transmission.

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3.12.5 Calculating Actual TX Data FIFO Usage

The following rules are used to calculate the actual TX data FIFO space consumed by a TX Packet:

TX command 'A' is stored in the TX data FIFO for every TX buffer.

TX command 'B' is written into the TX data FIFO when the First Segment (FS) bit is set in TX

command 'A.'

When TX checksum is enabled, the 4-byte TX checksum preamble is written into TX Data FIFO.

Any DWORD-long data added as part of the “Data Start Offset” is removed from each buffer before

the data is written to the TX data FIFO. Any data that is less than 1 DWORD is passed to the TX

data FIFO.

Payload from each buffer within a Packet is written into the TX data FIFO.

Any DWORD-long data added as part of the End Padding is removed from each buffer before the

data is written to the TX data FIFO. Any end padding that is less than 1 DWORD is passed to the

TX data FIFO.

10 No Carrier. When set, this bit indicates that the carrier signal from the transceiver was not present

during transmission.

Note: During 10/100 Mbps full-duplex transmission, the value of this bit is invalid and should be

ignored.

9Late Collision. When set, indicates that the packet transmission was aborted after the collision

window of 64 bytes.

8Excessive Collisions. When set, this bit indicates that the transmission was aborted after 16

collisions while attempting to transmit the current packet.

7Reserved. This bit is reserved. Always write zeros to this field to guarantee future compatibility.

6:3 Collision Count. This counter indicates the number of collisions that occurred before the packet was

transmitted. It is not valid when excessive collisions (bit 8) is also set.

2Excessive Deferral. If the deferred bit is set in the control register, the setting of the excessive

deferral bit indicates that the transmission has ended because of a deferral of over 24288 bit times

during transmission.

1Reserved. This bit is reserved. Always write zero to this bit to guarantee future compatibility.

0Deferred. When set, this bit indicates that the current packet transmission was deferred.

BITS DESCRIPTION

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3.12.6 Transmit Examples

3.12.6.1 TX Example 1

In this example a single, 111-Byte Ethernet packet will be transmitted. This packet is divided into three

buffers. The three buffers are as follows:

Buffer 0:

7-Byte “Data Start Offset”

79-Bytes of payload data

16-Byte “Buffer End Alignment”

Buffer 1:

0-Byte “Data Start Offset”

15-Bytes of payload data

16-Byte “Buffer End Alignment”

Buffer 2:

10-Byte “Data Start Offset”

17-Bytes of payload data

16-Byte “Buffer End Alignment”

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Figure 3.21, "TX Example 1" illustrates the TX command structure for this example, and also shows

how data is passed to the TX data FIFO.

Figure 3.21 TX Example 1

TX Command 'A'

031

TX Command 'B'

Pad DWORD 1

7-Byte Data Sta rt Offset

10-Byte

End Padding

79-Byte Payload

Buffer End Alignment = 1

Data Start Offset = 7

First Segment = 1

Last Segment = 0

Buf f er Size = 79

Packet Length = 111

TX Command 'A'

031

TX Command 'B'

10-Byte

End Offset Padding

15-Byte Payload

Buffer End Alignment = 1

Data Start Offset = 0

First Segment = 0

Last Segment = 0

Buf f er Size = 15

Packet Length = 111

TX Command 'A'

031

TX Command 'B'

Buffer End Alignment = 1

Data Start Off set = 10

First Segment = 0

Last Segment = 1

Buf f er Size = 17

Packet Length = 111

10-Byte

Data Start Offset

TX Command 'A'

TX Command 'B'

TX Command 'A'

TX Command 'B'

TX Command 'A'

TX Command 'B'

NOTE: Extra bytes

betw een buf f ers are

not transmitted

Data Written to the

Ethernet Controller

Data Passed to the

TX Data FIFO

5-Byte End Padding

17-Byte Payload Data

TX Command 'A'

TX Command 'B'

TX Command 'A'

79-Byte Payload

15-Byte Payload

17-Byte Payload

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3.12.6.2 TX Example 2

In this example, a single 183-Byte Ethernet packet will be transmitted. This packet is in a single buffer

as follows:

2-Byte “Data Start Offset”

183-Bytes of payload data

4-Byte “Buffer End Alignment”

Figure 3.22, "TX Example 2" illustrates the TX command structure for this example, and also shows

how data is passed to the TX data FIFO. Note that the packet resides in a single TX Buffer, therefore

both the FS and LS bits are set in TX command ‘A’.

Figure 3.22 TX Example 2

TX Command 'A'

031

TX Command 'B'

Data Written to the

Ethernet Controller

TX Command 'B'

183-Byte Payload Data

Data Start Offset = 6

First Segment = 1

Last Segment = 1

Buffer Size =183

Packet Length = 183

TX Command 'A'

TX Command 'B'

Data Passed to the

TX Data FIFO

Buffer End Alignment = 0

3B End Padding

TX Command 'A'

6-Byte Data Start Offset

183-Byte Payload Data

NOTE: Extra bytes between buffers

are not transmitted

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3.12.6.3 TX Example 3

In this example a single, 111-Byte Ethernet packet will be transmitted with a TX checksum. This packet

is divided into four buffers. The four buffers are as follows:

Buffer 0:

4-Byte “Data Start Offset”

4-Byte Checksum Preamble

16-Byte “Buffer End Alignment”

Buffer 1:

7-Byte “Data Start Offset”

79-Bytes of payload data

16-Byte “Buffer End Alignment”

Buffer 2:

0-Byte “Data Start Offset”

15-Bytes of payload data

16-Byte “Buffer End Alignment”

Buffer 3:

10-Byte “Data Start Offset”

17-Bytes of payload data

16-Byte “Buffer End Alignment”

Figure 3.21, "TX Example 1" illustrates the TX command structure for this example, and also shows

how data is passed to the TX data FIFO.

Note: In order to perform a TX checksum calculation on the associated packet, bit 14 (CK) of the TX

Command ‘B’ must be set in conjunction with bit 13 (FS) of TX Command ‘A’ and bit 16

(TXCOE_EN) of the COE_CR register. For more information, refer to Section 3.6.2, "Transmit

Checksum Offload Engine (TXCOE)".

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Figure 3.23 TX Example 3

031

TX Command 'B'

Pad DWORD 1

7-Byte Data Start Offset

10-Byte

End Padding

Buffer End Alignment = 1

Data Start Offset = 7

First Segment = 0

Last Segment = 0

Buffer Size = 79

031

TX Command 'B'

10-Byte

End Offset Padding

Buffer End Alignment = 1

Data Start Offset = 0

First Segment = 0

Last Segment = 0

Buffer Size = 15

031

TX Command 'B'

Buffer End Alignment = 1

Data Start Offset = 10

First Segment = 0

Last Segment = 1

Buffer Size = 17 10-Byte

Data Start Offset

TX Command 'A'

TX Command 'B'

TX Command 'A'

TX Command 'B'

TX Command 'A'

TX Command 'B'

NOTE: Extra bytes

between buffers are

not transmitted

Data Written to the

Ethernet Controller

Data Passed to the

TX Data FIFO

5-Byte End Padding

TX Command 'A'

TX Command 'B'

TX Command 'A'

79-Byte Payload

15-Byte Payload

17-Byte Payload

NOTE: When enabled, the TX Checksum

Preamble is pre-pended to data to be

transmitted. The FS bit in TX Command 'A', the

CK bit in TX Command 'B' and the TXCOE_EN

bit in the COE_CR register must all be set for

the TX checksum to be generated. FS must

not be set for subsequent fragments of the

same packet.

TX Command 'A'

031

TX Command 'B'

4-Byte Data Start Offset

8-Byte End Padding

Buffer End Alignment = 1

Data Start Offset = 4

First Segment = 1

Last Segment = 0

Buffer Size = 4

Packet Length = 115

TX Command 'A'

TX Command 'B'

TX Checksum Location = 50

Checksum Preamble

TX Checksum Start Pointer = 14

TX Command 'A'

TX Checksum Preamble

TX Command 'A'

79-Byte Payload

TX Command 'A'

15-Byte Payload

TX Command 'A'

17-Byte Payload Data

TX Checksum Enable = 1

Packet Length = 115

TX Checksum Enable = 1

Packet Length = 115

TX Checksum Enable = 1

Packet Length = 115

TX Checksum Enable = 1

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3.12.7 Transmitter Errors

If the Transmitter Error (TXE) flag is asserted for any reason, the transmitter will continue operation.

TX Error (TXE) will be asserted under the following conditions:

If the actual packet length count does not match the Packet Length field as defined in the TX

command.

Both TX command ‘A’ and TX command ‘B’ are required for each buffer in a given packet. TX

command ‘B’ must be identical for every buffer in a given packet. If the TX command ‘B’ words do

not match, the Ethernet controller will assert the Transmitter Error (TXE) flag.

Host overrun of the TX data FIFO.

Overrun of the TX status FIFO (unless TXSAO is enabled)

3.12.8 Stopping and Starting the Transmitter

To halt the transmitter, the host must set the TX_STOP bit in the TX_CFG register. The transmitter will

finish sending the current frame (if there is a frame transmission in progress). When the transmitter

has received the TX status for this frame, it will clear the TX_STOP and TX_ON bits, and will pulse

the TXSTOP_INT.

Once stopped, the host can optionally clear the TX status and TX data FIFOs. The host must re-enable

the transmitter by setting the TX_ON bit. If the there are frames pending in the TX data FIFO (i.e., TX

data FIFO was not purged), the transmission will resume with this data.

3.13 RX Data Path Operation

When an Ethernet Packet is received, the MIL first begins to transfer the RX data. This data is loaded

into the RX data FIFO. The RX data FIFO pointers are updated as data is written into the FIFO.

The last transfer from the MIL is the RX status word. The LAN9221/LAN9221i implements a separate

FIFO for the RX status words. The total available RX data and status queued in the RX FIFO can be

read from the RX_FIFO_INF register. The host may read any number of available RX status words

before reading the RX data FIFO.

The host must use caution when reading the RX data and status. The host must never read more data

than what is available in the FIFOs. If this is attempted an underrun condition will occur. If this error

occurs, the Ethernet controller will assert the Receiver Error (RXE) interrupt. If an underrun condition

occurs, a soft reset is required to regain host synchronization.

A configurable beginning offset is supported in the LAN9221/LAN9221i. The RX data Offset field in the

RX_CFG register controls the number of bytes that the beginning of the RX data buffer is shifted. The

host can set an offset from 0-31 bytes. The offset may be changed in between RX packets, but it must

not be changed during an RX packet read.

The LAN9221/LAN9221i can be programmed to add padding at the end of a receive packet in the

event that the end of the packet does not align with the host burst boundary. This feature is necessary

when the LAN9221/LAN9221i is operating in a system that always performs multi-DWORD bursts. In

such cases the LAN9221/LAN9221i must guarantee that it can transfer data in multiples of the Burst

length regardless of the actual packet length. When configured to do so, the LAN9221/LAN9221i will

add extra data at the end of the packet to allow the host to perform the necessary number of reads

so that the Burst length is not cut short. Once a packet has been padded by the H/W, it is the

responsibility of the host to interrogate the Packet length field in the RX status and determine how

much padding to discard at the end of the Packet.

It is possible to read multiple packets out of the RX data FIFO in one continuous stream. It should be

noted that the programmed Offset and Padding will be added to each individual packet in the stream,

since packet boundaries are maintained.

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3.13.1 RX Slave PIO Operation

Using PIO mode, the host can either implement a polling or interrupt scheme to empty the received

packet out of the RX data FIFO. The host will remain in the idle state until it receives an indication

(interrupt or polling) that data is available in the RX data FIFO. The host will then read the RX status

FIFO to get the packet status, which will contain the packet length and any other status information.

The host should perform the proper number of reads, as indicated by the packet length plus the start

offset and the amount of optional padding added to the end of the frame, from the RX data FIFO.

Figure 3.24 Host Receive Routine Using Interrupts

Figure 3.25 Host Receive Routine with Polling

Not Last Packet

Idle

Read RX

Status

DWORD

init

Read RX

Packet

Last Packet

RX Interrupt

Read

RX_FIFO_

INf

Read RX

Status

DWORD

init

Read RX

Packet

Last Packet

Not Last Packet

Valid Status DWORD

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3.13.1.1 Receive Data FIFO Fast Forward

The RX data path implements an automatic data discard function. Using the RX data FIFO Fast

Forward bit (RX_FFWD) in the RX_DP_CTRL register, the host can instruct the LAN9221/LAN9221i

to skip the packet at the head of the RX data FIFO. The RX data FIFO pointers are automatically

incremented to the beginning of the next RX packet.

When performing a fast-forward, there must be at least 4 DWORDs of data in the RX data FIFO for

the packet being discarded. For less than 4 DWORDs do not use RX_FFWD. In this case data must

be read from the RX data FIFO and discarded using standard PIO read operations.

After initiating a fast-forward operation, do not perform any reads of the RX data FIFO until the

RX_FFWD bit is cleared. Other resources can be accessed during this time (i.e., any registers and/or

the other three FIFOs). Also note that the RX_FFWD will only fast-forward the RX data FIFO, not the

RX status FIFO.

The receiver does not have to be stopped to perform a fast-forward operation.

3.13.1.2 Force Receiver Discard (Receiver Dump)

In addition to the Receive data Fast Forward feature, LAN9221/LAN9221i also implements a receiver

"dump" feature. This feature allows the host processor to flush the entire contents of the RX data and

RX status FIFOs. When activated, the read and write pointers for the RX data and status FIFOs will

be returned to their reset state. To perform a receiver dump, the LAN9221/LAN9221i receiver must be

halted. Once the receiver stop completion is confirmed, the RX_DUMP bit can be set in the RX_CFG

the receiver, please refer to Section 3.13.4, "Stopping and Starting the Receiver," on page 66. For more

information on the RX_DUMP bit, please refer to Section 5.3.7, "RX_CFG—Receive Configuration

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3.13.2 RX Packet Format

The RX status words can be read from the RX status FIFO port, while the RX data packets can be

read from the RX data FIFO. RX data packets are formatted in a specific manner before the host can

read them as shown in Figure 3.26. It is assumed that the host has previously read the associated

status word from the RX status FIFO, to ascertain the data size and any error conditions.

Figure 3.27 shows the RX packet format when the RX checksum is enabled. The RX checksum data

appended to the data payload is treated just as an additional 4-bytes within the RX Data FIFO. The

RX checksum is enabled by setting the RXCOE_EN bit in the COE_CR—Checksum Offload Engine

Control Register. For more information on the RX checksum, refer to Section 3.6.1, "Receive

Checksum Offload Engine (RXCOE)".

Figure 3.26 RX Packet Format

ofs + First Data DWORD

Last Data DWORD

031

Host Read

Order

1st

2nd

Last

Optional Pad DWORD0

Optional Pad DWORDn

Optional offset DWORD0

Optional offset DWORDn

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3.13.3 RX Status Format

Figure 3.27 RX Packet Format with RX Checksum

BITS DESCRIPTION

31 Reserved. This bit is reserved. Reads 0.

30 Filtering Fail. When set, this bit indicates that the associated frame failed the address recognizing

filtering.

29:16 Packet Length. The size, in bytes, of the corresponding received frame.

15 Error Status (ES). When set this bit indicates that the MIL has reported an error. This bit is the

Internal logical “or” of bits 11,7,6 and 1.

14 Reserved. These bits are reserved. Reads 0.

13 Broadcast Frame. When set, this bit indicates that the received frame has a Broadcast address.

12 Length Error (LE). When set, this bit indicates that the actual length does not match with the

length/type field of the received frame.

11 Runt Frame. When set, this bit indicates that frame was prematurely terminated before the collision

window (64 bytes). Runt frames are passed on to the host only if the Pass Bad Frames bit MAC_CR

Bit [16] is set.

10 Multicast Frame. When set, this bit indicates that the received frame has a Multicast address.

9:8 Reserved. These bits are reserved. Reads 0.

ofs + First Data DWORD

Last Data DWORD

031

Host Read

Order

1st

2nd

Last

Optional Pad DWORD0

Optional Pad DWORDn

Optional offset DWORD0

Optional offset DWORDn

Checksum

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3.13.4 Stopping and Starting the Receiver

To stop the receiver, the host must clear the RXEN bit in the MAC Control Register. When the receiver

is halted, the RXSTOP_INT will be pulsed. Once stopped, the host can optionally clear the RX status

and RX data FIFOs. The host must re-enable the receiver by setting the RXEN bit.

3.13.5 Receiver Errors

If the Receiver Error (RXE) flag is asserted for any reason, the receiver will continue operation. RX

Error (RXE) will be asserted under the following conditions:

A host underrun of RX data FIFO

A host underrun of the RX status FIFO

An overrun of the RX status FIFO

It is the duty of the host to identify and resolve any error conditions.

7Frame Too Long. When set, this bit indicates that the frame length exceeds the maximum Ethernet

specification of 1518 bytes. This is only a frame too long indication and will not cause the frame

reception to be truncated.

6Collision Seen. When set, this bit indicates that the frame has seen a collision after the collision

window. This indicates that a late collision has occurred.

5Frame Type. When set, this bit indicates that the frame is an Ethernet-type frame (Length/Type field

in the frame is greater than 1500). When reset, it indicates the incoming frame was an 802.3 type

frame. This bit is not set for Runt frames less than 14 bytes.

4Receive Watchdog time-out. When set, this bit indicates that the incoming frame is greater than

2048 bytes through 2560 bytes, therefore expiring the Receive Watchdog Timer.

3MII Error. When set, this bit indicates that a receive error (RX_ER asserted) was detected during

frame reception.

2Dribbling Bit. When set, this bit indicates that the frame contained a non-integer multiple of 8 bits.

This error is reported only if the number of dribbling bits in the last byte is 4 in the MII operating mode,

or at least 3 in the 10 Mbps operating mode. This bit will not be set when the collision seen bit[6] is

set. If set and the CRC error bit[1] is cleared, then the packet is considered to be valid.

1CRC Error. When set, this bit indicates that a CRC error was detected. This bit is also set when the

RX_ER pin is asserted during the reception of a frame even though the CRC may be correct. This bit

is not valid if the received frame is a Runt frame, or a late collision was detected or when the

Watchdog Time-out occurs.

0Reserved. These bits are reserved. Reads 0

BITS DESCRIPTION

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Chapter 4 Internal Ethernet PHY

4.1 Top Level Functional Description

Functionally, the internal PHY can be divided into the following sections:

100Base-TX transmit and receive

10Base-T transmit and receive

Internal MII interface to the Ethernet Media Access Controller

Auto-negotiation to automatically determine the best speed and duplex possible

Management Control to read status registers and write control registers

Figure 4.1 100Base-TX Data Path

4.2 100Base-TX Transmit

The data path of the 100Base-TX is shown in Figure 4.1. Each major block is explained below.

4.2.1 4B/5B Encoding

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 b le 4.1. 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.

The encoding process may be bypassed by clearing bit 6 of register 31. When the encoding is

bypassed the 5th transmit data bit is equivalent to TX_ER.

MAC

Driver

MLT-3

Converter

NRZI

Converter

4B/5B

Encoder

Magnetics

CAT-5RJ45

100M

PLL

Internal

MII 25 MHz by 4 bits

TX_CLK

25MHz by

5 bits

NRZI

MLT-3

Scrambler

and PISO

125 Mbps Serial

MII 25MHz

by 4 bits

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Table 4.1 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 TX_EN

11000 J First nibble of SSD, translated to “0101”

following IDLE, else RX_ER

Sent for rising TX_EN

10001 K Second nibble of SSD, translated to

“0101” following J, else RX_ER

Sent for rising TX_EN

01101 T First nibble of ESD, causes de-assertion

of CRS if followed by /R/, else assertion

of RX_ER

Sent for falling TX_EN

00111 R Second nibble of ESD, causes

deassertion of CRS if following /T/, else

assertion of RX_ER

Sent for falling TX_EN

00100 H Transmit Error Symbol Sent for rising TX_ER

00110 V INVALID, RX_ER if during RX_DV INVALID

11001 V INVALID, RX_ER if during RX_DV INVALID

00000 V INVALID, RX_ER if during RX_DV INVALID

00001 V INVALID, RX_ER if during RX_DV INVALID

00010 V INVALID, RX_ER if during RX_DV INVALID

00011 V INVALID, RX_ER if during RX_DV INVALID

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4.2.2 Scrambling

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.

4.2.3 NRZI and MLT3 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 encoded to MLT-3. MLT3 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”.

4.2.4 100M Transmit Driver

The MLT3 data is then passed to the analog transmitter, which launches the differential MLT-3 signal,

on outputs TXP and TXN, to the twisted pair media via 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.

4.2.5 100M Phase Lock Loop (PLL)

The 100M PLL locks onto reference clock and generates the 125MHz clock used to drive the 125 MHz

logic and the 100Base-Tx Transmitter.

00101 V INVALID, RX_ER if during RX_DV INVALID

01000 V INVALID, RX_ER if during RX_DV INVALID

01100 V INVALID, RX_ER if during RX_DV INVALID

10000 V INVALID, RX_ER if during RX_DV INVALID

Table 4.1 4B/5B Code Table (continued)

CODE

GROUP SYM

RECEIVER

INTERPRETATION

TRANSMITTER

INTERPRETATION

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Figure 4.2 Receive Data Path

4.3 100Base-TX Receive

The receive data path is shown in Figure 4.2. Detailed descriptions are given below.

4.3.1 100M Receive Input

The MLT-3 from the cable is fed into the PHY (on inputs RXP and RXN) 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 quanitizer it generates 6 digital bits to represent each sample. The DSP adjusts the gain of the

ADC according to the observed signal levels such that the full dynamic range of the ADC can be used.

4.3.2 Equalizer, Baseline Wander Correction and Clock and 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 consisting of 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.

4.3.3 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.

MAC

A/D

Converter

MLT-3

Converter

NRZI

Converter

4B/5B

Decoder

Magnetics CAT-5RJ45

100M

PLL

Internal

MII 25MHz by 4 bits

RX_CLK

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 25MHz

by 4 bits

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4.3.4 Descrambling

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 descrambler can be bypassed by setting bit 0 of register 31.

4.3.5 Alignment

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.

4.3.6 5B/4B Decoding

The 5-bit code-groups are translated into 4-bit data nibbles according to the 4B/5B table. 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 internal RX_DV signal, indicating that valid data is available on the

Internal 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 the internal carrier sense and RX_DV.

These symbols are not translated into data.

4.4 10Base-T Transmit

Data to be transmitted comes from the MAC layer controller. The 10Base-T transmitter receives 4-bit

nibbles from the 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.

The 10M transmitter uses the following blocks:

MII (digital)

TX 10M (digital)

10M Transmitter (analog)

10M PLL (analog)

4.4.1 10M Transmit Data across the internal MII bus

The MAC controller drives the transmit data onto the internal TXD BUS. When the controller has driven

TX_EN high to indicate valid data, the data is latched by the MII block on the rising edge of TX_CLK.

The data is in the form of 4-bit wide 2.5MHz data.

4.4.2 Manchester Encoding

The 4-bit wide data is sent to the TX10M 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

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clock. This is used to Manchester encode the NRZ data stream. When no data is being transmitted

(TX_EN is low), the TX10M block outputs Normal Link Pulses (NLPs) to maintain communications with

the remote link partner.

4.4.3 10M Transmit Drivers

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 TXP and TXN outputs.

4.5 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 MII at

a rate of 2.5MHz.

This 10M receiver uses the following blocks:

Filter and SQUELCH (analog)

10M PLL (analog)

RX 10M (digital)

MII (digital)

4.5.1 10M Receive Input and Squelch

The Manchester signal from the cable is fed into the PHY (on inputs RXP and RXN) 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.

4.5.2 Manchester Decoding

The output of the SQUELCH goes to the RX10M 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

is indicated by the flag “XPOL“, bit 4 in register 27. The 10M PLL is locked onto the received

Manchester signal and from this, generates the received 20MHz clock. 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.

4.5.3 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 TX_EN input for

a long period. Special logic is used to detect the jabber state and abort the transmission to the line,

within 45ms. Once TX_EN is deasserted, the logic resets the jabber condition.

4.6 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

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performance mode of operation supported by both sides. Auto-negotiation is fully defined in clause 28

of the IEEE 802.3 specification.

Once auto-negotiation has completed, information about the resolved link can be passed back to the

controller via the internal Serial Management Interface (SMI). The results of the negotiation process

are reflected in the Speed Indication bits in register 31, as well as the Link Partner Ability Register

(Register 5).

The auto-negotiation protocol is a purely physical layer activity and proceeds independently of the MAC

controller.

The advertised capabilities of the PHY are stored in register 4 of the SMI registers. The default

advertised by the PHY is determined by user-defined on-chip signal options.

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)

10M PLL (analog)

10M Transmitter (analog)

When enabled, auto-negotiation is started by the occurrence of one of the following events:

Hardware reset

Software reset

Power-down reset

Link status down

Setting register 0, bit 9 high (auto-negotiation restart)

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 transmitter. 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 register 4 of the

SMI registers.

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

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 operation.

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Once a capability 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 not all of the required FLP bursts are received.

Writing register 4 bits [8:5] allows software control of the capabilities advertised by the PHY. Writing

abilities will be advertised. Auto-negotiation can also be disabled via software by clearing register 0,

bit 12.

The LAN9221/LAN9221i does not support “Next Page" capability.

4.7 Parallel Detection

If the LAN9221/LAN9221i 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 standard.

This ability is known as “Parallel Detection. This feature ensures inter operability with legacy link

partners. If a link is formed via parallel detection, then bit 0 in register 6 is cleared to indicate that the

Link Partner is not capable of auto-negotiation. The Ethernet MAC has access to this information via

the management interface. If a fault occurs during parallel detection, bit 4 of register 6 is set.

If the Link Partner is not auto-negotiation capable, then register 5 is updated after completion of parallel

detection to reflect the speed capability of the Link Partner.

4.7.1 Re-starting Auto-negotiation

Auto-negotiation can be re-started at any time by setting register 0, bit 9. 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 bit 9 of the control register, the

LAN9221/LAN9221i will respond by stopping all transmission/receiving operations. Once the

break_link_timer is done, in the Auto-negotiation state-machine (approximately 1200ms) the auto-

negotiation will re-start. The Link Partner will have also dropped the link due to lack of a received

signal, so it too will resume auto-negotiation.

4.7.2 Disabling Auto-negotiation

Auto-negotiation can be disabled by setting register 0, bit 12 to zero. The device will then force its

speed of operation to reflect the information in register 0, bit 13 (speed) and register 0, bit 8 (duplex).

The speed and duplex bits in register 0 should be ignored when auto-negotiation is enabled.

4.7.3 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 internal carrier sense signal, CRS,

responds to both transmit and receive activity. In this mode, 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, the

internal CRS responds only to receive activity. The CSMA/CD protocol does not apply and collision

detection is disabled.

Table 4.2 describes the behavior of the internal CRS bit under all receive/transmit conditions. The

internal CRS signal is used to trigger bit 10 (No Carrier) of the TX Status word (See Section 3.12.4,

"TX Status Format"). The CRS value, and subsequently the No Carrier value, are invalid during any

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full-duplex transmission. Therefore, these signals cannot be used as a verification method of

transmitted packets when transmitting in 10/100 Mbps full-duplex modes.

Note 4.1 The LAN9221/LAN9221i 10/100 PHY internal CRS signal operates in two modes: Active

and Low. When in Active mode, the internal CRS will transition high and low upon line

activity, where a high value indicates a carrier has been detected. In Low mode, the

internal CRS stays low and does not indicate carrier detection. The internal CRS signal

and No Carrier (bit 10 of the TX Status word) cannot be used as a verification method of

transmitted packets when transmitting in 10/100 Mbps full-duplex mode.

4.8 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 4.3, the SMSC LAN9221/LAN9221i Auto-MDIX

PHY is capable of configuring the TPO and TPI 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 an internal register 27.15, or the external control pins

AMDIX_EN. When disabled the TX and RX pins can be configured with the Channel Select

(CH_SELECT) pin as desired.

Table 4.2 CRS Behavior

MODE SPEED DUPLEX ACTIVITY

CRS BEHAVIOR

(Note 4.1)

Manual 10 Mbps Half-Duplex Transmitting Active

Manual 10 Mbps Half-Duplex Receiving Active

Manual 10 Mbps Full-Duplex Transmitting Low

Manual 10 Mbps Full-Duplex Receiving Active

Manual 100 Mbps Half-Duplex Transmitting Active

Manual 100 Mbps Half-Duplex Receiving Active

Manual 100 Mbps Full-Duplex Transmitting Low

Manual 100 Mbps Full-Duplex Receiving Active

Auto-Negotiation 10 Mbps Half-Duplex Transmitting Active

Auto-Negotiation 10 Mbps Half-Duplex Receiving Active

Auto-Negotiation 10 Mbps Full-Duplex Transmitting Low

Auto-Negotiation 10 Mbps Full-Duplex Receiving Active

Auto-Negotiation 100 Mbps Half-Duplex Transmitting Active

Auto-Negotiation 100 Mbps Half-Duplex Receiving Active

Auto-Negotiation 100 Mbps Full-Duplex Transmitting Low

Auto-Negotiation 100 Mbps Full-Duplex Receiving Active

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The figure below shows the signal names at the RJ-45 connector, The mapping of these signals to the pins on

the LAN9221/LAN9221i is as follows:

TXP = TPO+

TXN = TPO-

RXP = TPI+

RXN = TPI-

Figure 4.3 Direct Cable Connection vs. Cross-over Cable Connection

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Chapter 5 Register Description

The following section describes all LAN9221/LAN9221i registers and data ports.

Figure 5.1 Memory Map

MAC CS R Port

A4h

B0h

Base + 00h

RESERVED

B4h

A0h

RX Data FIFO Port

TX Data FIFO Port

RX Status FIFO Por t40h

20h

50h

FCh

EEPROM Port

04h

1Ch

RX Dat a FIFO Alias Po r ts

24h

3Ch

TX Dat a FIFO Alias Por ts

RX Status FIFO PEEK44h

TX Status FIFO Port48h

TX St at u s FIFO PEEK4Ch

A8h

ACh

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5.1 Register Nomenclature and Access Attributes

5.2 RX and TX FIFO Ports

The LAN9221/LAN9221i contains four host-accessible FIFOs: RX Status, RX Data, TX Status, and TX

Data FIFOs. The sizes Data FIFOs and the RX Status FIFO are configurable through the CSRs.

5.2.1 RX FIFO Ports

The RX Data Path contains two Read-Only FIFOs: RX Status and RX Data. The RX Status FIFO has

two ports at different address locations. The RX Status FIFO Port causes the top of the RX Status

FIFO to be “popped”, and is destructive. The RX Status FIFO PEEK Port allows the top of the RX

Status FIFO to be read without “popping” it.

The RX Data FIFO has a single port; reading data from this port always causes the top of the RX Data

FIFO to be “popped”. This port is aliased to 16 WORD locations. The host may access the top of the

RX Data FIFO through any of these locations.

5.2.2 TX FIFO Ports

The TX Data Path consists of two FIFOs, TX Status and RX Data. The TX Status FIFO also has two

ports at different locations. When the TX Status FIFO Port is read, the top of the TX Status FIFO is

popped. When the TX Status FIFO PEEK Port is read, the top of the TX Status FIFO is not popped.

The TX data FIFO is Write Only. It is aliased to 16 WORD locations . The host may access the top of

the TX Data FIFO through any of these locations.

SYMBOL DESCRIPTION

RO Read Only: If a register is read only, writes to this register have no effect.

WO Write Only: If a register is write only, reads always return 0.

R/W Read/Write: A register with this attribute can be read and written

R/WC Read/Write Clear: A register bit with this attribute can be read and written. However, a write of a 1

clears (sets to 0) the corresponding bit and a write of a 0 has no effect.

RC Read to Clear: A register bit with this attribute is cleared when read.

LL Latch Low: Clear on read of register

LH Latch High: Clear on read of register

SC Self-Clearing

NASR Not Affected by Software Reset

Reserved

Bits

Certain bits within registers are listed as “Reserved”. Unless stated otherwise, these bits must be

written with zeros for future compatibility. The values of these bits are not guaranteed when read.

Reserved

Registers

Certain configuration registers within the LAN9221/LAN9221i are listed as “Reserved”. These

registers are not guaranteed to return any particular value when read. These registers must not be

written to or modified by system failure; doing so could result in failure of the device and system.

Default

States

At Reset - System reset or Software Reset - internal registers are set to their default states.

The default states provide a minimum level of functionality needed to successfully bring up a system,

but do not necessarily provide desired or optimal configuration of the device. It is the responsibility

of the system initialization software to properly determine the operating parameters and optional

system features that are applicable, and to program the LAN9221/LAN9221i registers accordingly.

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5.3 System Control and Status Registers

Table 5.1, "Direct Address Register Map", lists the registers that are directly addressable by the host

bus.

Table 5.1 Direct Address Register Map

CONTROL AND STATUS REGISTERS

BASE ADDRESS

+ OFFSET SYMBOL REGISTER NAME DEFAULT

50h ID_REV Chip ID and Revision. See Page 80.

54h IRQ_CFG Main Interrupt Configuration 00000000h

58h INT_STS Interrupt Status 00000000h

5Ch INT_EN Interrupt Enable Register 00000000h

60h RESERVED Reserved for future use -

64h BYTE_TEST Read-only byte order testing register 87654321h

68h FIFO_INT FIFO Level Interrupts 48000000h

6Ch RX_CFG Receive Configuration 00000000h

70h TX_CFG Transmit Configuration 00000000h

74h HW_CFG Hardware Configuration 00050000h

78h RX_DP_CTL RX Datapath Control 00000000h

7Ch RX_FIFO_INF Receive FIFO Information 00000000h

80h TX_FIFO_INF Transmit FIFO Information 00001200h

84h PMT_CTRL Power Management Control 00000000h

88h GPIO_CFG General Purpose IO Configuration 00000000h

8Ch GPT_CFG General Purpose Timer Configuration 0000FFFFh

90h GPT_CNT General Purpose Timer Count 0000FFFFh

94h RESERVED Reserved for future use -

98h WORD_SWAP WORD SWAP Register 00000000h

9Ch FREE_RUN Free Run Counter -

A0h RX_DROP RX Dropped Frames Counter 00000000h

A4h MAC_CSR_CMD MAC CSR Synchronizer Command (MAC

CSR’s are indexed through this register)

00000000h

A8h MAC_CSR_DATA MAC CSR Synchronizer Data 00000000h

ACh AFC_CFG Automatic Flow Control Configuration 00000000h

B0h E2P_CMD EEPROM Command 00000000h

B4h E2P_DATA EEPROM Data 00000000h

B8h - FCh RESERVED Reserved for future use -

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5.3.1 ID_REV—Chip ID and Revision

This register contains the ID and Revision fields for this design.

5.3.2 IRQ_CFG—Interrupt Configuration Register

This register configures and indicates the state of the IRQ signal.

Offset: 50h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31-16 Chip ID. This read-only field identifies this design RO 9221h

15-0 Chip Revision RO 0000h

Offset: 54h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31:24 Interrupt Deassertion Interval (INT_DEAS). This field determines the

Interrupt Request Deassertion 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.

Note: This field does not apply to the PME interrupt.

R/W 0

23-15 Reserved RO -

14 Interrupt Deassertion Interval Clear (INT_DEAS_CLR). Writing a one

to this register clears the de-assertion counter in the IRQ Controller, thus

causing a new de-assertion interval to begin (regardless of whether or

not the IRQ Controller is currently in an active de-assertion interval).

SC 0

13 Interrupt Deassertion Status (INT_DEAS_STS). When set, this bit

indicates that interrupts are currently in a deassertion interval, and will

not be delivered to the IRQ pin. When this bit is clear, interrupts are not

currently in a deassertion interval, and will be delivered to the IRQ pin.

SC 0

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 high, one of the

enabled interrupts is currently active.

RO 0

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

deasserted. This bit has no effect on any internal interrupt status bits.

R/W 0

7-5 Reserved RO -

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4IRQ Polarity (IRQ_POL) – When cleared, enables the IRQ line to

function as an active low output. When set, the IRQ output is active high.

When IRQ is configured as an open-drain output this field is ignored,

and the interrupt output is always active low.

R/W

NASR

3-1 Reserved RO -

0IRQ Buffer Type (IRQ_TYPE) – When cleared, enables IRQ to function

as an open-drain buffer for use in a Wired-Or Interrupt configuration.

When set, the IRQ output is a Push-Pull driver. When configured as an

open-drain output the IRQ_POL field is ignored, and the interrupt output

is always active low.

R/W

NASR

BITS DESCRIPTION TYPE DEFAULT

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5.3.3 INT_STS—Interrupt Status Register

This register contains the current status of the generated interrupts. Writing a 1 to the corresponding

bits acknowledges and clears the interrupt.

Offset: 58h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31 Software Interrupt (SW_INT). This interrupt is generated when the

SW_INT_EN bit is set high. Writing a one clears this interrupt.

R/WC 0

30-26 Reserved RO -

25 TX Stopped (TXSTOP_INT). This interrupt is issued when STOP_TX bit

in TX_CFG is set, and the transmitter is halted.

R/WC 0

24 RX Stopped (RXSTOP_INT). This interrupt is issued when the receiver is

halted.

R/WC 0

23 RX Dropped Frame Counter Halfway (RXDFH_INT). This interrupt is

issued when the RX Dropped Frames Counter counts past its halfway

point (7FFFFFFFh to 80000000h).

R/WC 0

22 Reserved RO 0

21 TX IOC Interrupt (TX_IOC). When a buffer with the IOC flag set has

finished being loaded into the TX FIFO, this interrupt is generated.

R/WC 0

20 RX DMA Interrupt (RXD_INT). This interrupt is issued when the amount

of data programmed in the RX DMA Count (RX_DMA_CNT) field of the

RX_CFG register has been transferred out of the RX FIFO.

R/WC 0

19 GP Timer (GPT_INT). This interrupt is issued when the General Purpose

timer wraps past zero to FFFFh.

R/WC 0

18 PHY (PHY_INT). Indicates a PHY Interrupt event. RO 0

17 Power Management Event Interrupt (PME_INT). This interrupt is issued

when a Power Management Event is detected as configured in the

PMT_CTRL register. This interrupt functions independent of the PME

signal, and will still function if the PME signal is disabled. Writing a '1'

clears this bit regardless of the state of the PME hardware signal.

Notes:

Detection of a Power Management Event, and assertion of the PME

signal will not wakeup the LAN9221/LAN9221i. The LAN9221/LAN9221i

will only wake up when it detects a host write cycle of any data to the

BYTE_TEST register.

The Interrupt Deassertion interval does not apply to the PME interrupt.

R/WC 0

16 TX Status FIFO Overflow (TXSO). Generated when the TX Status

FIFO overflows.

R/WC 0

15 Receive Watchdog Time-out (RWT). Interrupt is generated when a

packet larger than 2048 bytes has been received.

R/WC 0

14 Receiver Error (RXE). Indicates that the receiver has encountered an

error. Please refer to Section 3.13.5, "Receiver Errors," on page 66 for a

description of the conditions that will cause an RXE.

R/WC 0

13 Transmitter Error (TXE). When generated, indicates that the

transmitter has encountered an error. Please refer to Section 3.12.7,

"Transmitter Errors," on page 61, for a description of the conditions that

will cause a TXE.

R/WC 0

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12:11 Reserved RO -

10 TX Data FIFO Overrun Interrupt (TDFO). Generated when the TX data

FIFO is full, and another write is attempted.

R/WC 0

9TX Data FIFO Available Interrupt (TDFA). Generated when the TX data

FIFO available space is greater than the programmed level.

R/WC 0

8TX Status FIFO Full Interrupt (TSFF). Generated when the TX Status

FIFO is full.

R/WC 0

7TX Status FIFO Level Interrupt (TSFL). Generated when the TX Status

FIFO reaches the programmed level.

R/WC 0

6RX Dropped Frame Interrupt (RXDF_INT). This interrupt is issued

whenever a receive frame is dropped.

R/WC 0

5Reserved RO -

4RX Status FIFO Full Interrupt (RSFF). Generated when the RX Status

FIFO is full.

R/WC 0

3RX Status FIFO Level Interrupt (RSFL). Generated when the RX Status

FIFO reaches the programmed level.

R/WC 0

2-0 GPIO [2:0] (GPIOx_INT). Interrupts are generated from the GPIO’s.

These interrupts are configured through the GPIO_CFG register.

R/WC 000

BITS DESCRIPTION TYPE DEFAULT

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5.3.4 INT_EN—Interrupt Enable Register

This register contains the interrupt masks for IRQ. Writing 1 to any of the bits enables the

corresponding interrupt as a source for IRQ. Bits in the 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.

Offset: 5Ch Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31 Software Interrupt (SW_INT_EN) R/W 0

30:26 Reserved RO -

25 TX Stopped Interrupt Enable (TXSTOP_INT_EN) R/W 0

24 RX Stopped Interrupt Enable (RXSTOP_INT_EN) R/W 0

23 RX Dropped Frame Counter Halfway Interrupt Enable (RXDFH_INT_EN). R/W 0

22 Reserved RO 0

21 TX IOC Interrupt Enable (TIOC_INT_EN) R/W 0

20 RX DMA Interrupt (RXD_INT). R/W 0

19 GP Timer (GPT_INT_EN) R/W 0

18 PHY (PHY_INT_EN) R/W 0

17 Power Management Event Interrupt Enable (PME_INT_EN) R/W 0

16 TX Status FIFO Overflow (TXSO_EN) R/W 0

15 Receive Watchdog Time-out Interrupt (RWT_INT_EN) R/W 0

14 Receiver Error Interrupt (RXE_INT_EN) R/W 0

13 Transmitter Error Interrupt (TXE_INT_EN) R/W 0

12:11 Reserved RO -

10 TX Data FIFO Overrun Interrupt (TDFO_INT_EN) R/W 0

9 TX Data FIFO Available Interrupt (TDFA_INT_EN) R/W 0

8 TX Status FIFO Full Interrupt (TSFF_INT_EN) R/W 0

7 TX Status FIFO Level Interrupt (TSFL_INT_EN) R/W 0

6 RX Dropped Frame Interrupt Enable (RXDF_INT_EN) R/W 0

5 Reserved RO -

4 RX Status FIFO Full Interrupt (RSFF_INT_EN) R/W 0

3 RX Status FIFO Level Interrupt (RSFL_INT_EN) R/W 0

2-0 GPIO [2:0] (GPIOx_INT_EN). R/W 000

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5.3.5 BYTE_TEST—Byte Order Test Register

This register can be used to determine the byte ordering of the current configuration

5.3.6 FIFO_INT—FIFO Level Interrupts

This register configures the limits where the FIFO Controllers will generate system interrupts.

Offset: 64h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31:0 Byte Test RO 87654321h

Offset: 68h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31-24 TX Data Available Level. The value in this field sets the level, in number

of 64 Byte blocks, at which the TX FIFO Available interrupt (TFDA) will be

generated. When the TX data FIFO free space is greater than this value a

TX FIFO Available interrupt (TDFA) will be generated.

R/W 48h

23-16 TX Status Level. The value in this field sets the level, in number of

DWORDs, at which the TX Status FIFO Level interrupt (TSFL) will be

generated. When the TX Status FIFO used space is greater than this value

an TX Status FIFO Level interrupt (TSFL) will be generated.

R/W 00h

15-8 Reserved RO -

7-0 RX Status Level. The value in this field sets the level, in number of

DWORDs, at which the RX Status FIFO Level interrupt (RSFL) will be

generated. When the RX Status FIFO used space is greater than this value

an RX Status FIFO Level interrupt (RSFL) will be generated.

R/W 00h

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5.3.7 RX_CFG—Receive Configuration Register

This register controls the LAN9221/LAN9221i receive engine.

Offset: 6Ch Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31:30 RX End Alignment. This field specifies the alignment that must be

maintained on the last data transfer of a buffer. The LAN9221/LAN9221i

will add extra DWORDs of data up to the alignment specified in the table

below. The host is responsible for removing these extra DWORDs. This

mechanism can be used to maintain cache line alignment on host

processors.

Please refer to Table 5. 2 for bit definitions

Note: The desired RX End Alignment must be set before reading a

packet. The RX end alignment can be changed between reading

receive packets, but must not be changed if the packet is

partially read.

R/W 00b

29-28 Reserved RO -

27-16 RX DMA Count (RX_DMA_CNT). This 12-bit field indicates the amount

of data, in DWORDS, to be transferred out of the RX data FIFO before

asserting the RXD_INT. After being set, this field is decremented for each

DWORD of data that is read from the RX data FIFO. This field can be

overwritten with a new value before it reaches zero.

R/W 000h

15 Force RX Discard (RX_DUMP). This self-clearing bit clears the RX data

and status FIFOs of all pending data. When a ‘1’ is written, the RX data

and status pointers are cleared to zero.

Note: Please refer to section “Force Receiver Discard (Receiver

Dump)” on page 63 for a detailed description regarding the use

of RX_DUMP.

SC 0

14-13 Reserved RO -

12-8 RX Data Offset (RXDOFF). This field controls the offset value, in bytes,

that is added to the beginning of an RX data packet. The start of the valid

data will be shifted by the number of bytes specified in this field. An offset

of 0-31 bytes is a valid number of offset bytes.

Note: The two LSBs of this field (D[9:8]) must not be modified while

the RX is running. The receiver must be halted, and all data

purged before these two bits can be modified. The upper three

bits (DWORD offset) may be modified while the receiver is

running. Modifications to the upper bits will take affect on the

next DWORD read.

R/W 00000

7-0 Reserved RO -

Table 5.2 RX Alignment Bit Definitions

[31] [30] End Alignment

0 0 4-byte alignment

0 1 16-byte alignment

1 0 32-byte alignment

11 Reserved

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5.3.8 TX_CFG—Transmit Configuration Register

This register controls the transmit functions on the LAN9221/LAN9221i Ethernet Controller.

Offset: 70h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31-16 Reserved. RO -

15 Force TX Status Discard (TXS_DUMP). This self-clearing bit clears the TX

status FIFO of all pending status DWORD’s. When a ‘1’ is written, the TX

status pointers are cleared to zero.

SC 0

14 Force TX Data Discard (TXD_DUMP). This self-clearing bit clears the TX

data FIFO of all pending data. When a ‘1’ is written, the TX data pointers

are cleared to zero.

SC 0

13-3 Reserved RO -

2TX Status Allow Overrun (TXSAO). When this bit is cleared, data

transmission is suspended if the TX Status FIFO becomes full. Setting this

bit high allows the transmitter to continue operation with a full TX Status

FIFO.

Note: This bit does not affect the operation of the TX Status FIFO Full

interrupt.

R/W 0

1Transmitter Enable (TX_ON). When this bit is set (1), the transmitter is

enabled. Any data in the TX FIFO will be sent. This bit is cleared

automatically when STOP_TX is set and the transmitter is halted.

R/W 0

0Stop Transmitter (STOP_TX). When this bit is set (1), the transmitter will

finish the current frame, and will then stop transmitting. When the transmitter

has stopped this bit will clear. All writes to this bit are ignored while this bit

is high.

SC 0

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5.3.9 HW_CFG—Hardware Configuration Register

Note: The transmitter and receiver must be stopped before writing to this register. Refer to Section

3.12.8, "Stopping and Starting the Transmitter," on page 61 and Section 3.13.4, "Stopping and

Starting the Receiver," on page 66 for details on stopping the transmitter and receiver.

Offset: 74h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31 Reserved RO -

30 Reserved RO -

29 FIFO Port Endian Ordering (FPORTEND). This control bit determines the

endianess of RX and TX data FIFO host accesses when accessed through

the RX/TX Data FIFO ports, including the alias addresses (any access from

00h to 3Ch). When this bit is cleared, data FIFO port accesses utilize little

endian byte ordering. When this bit is set, data FIFO port accesses utilize

big endian byte ordering. Please refer to section Section 3.7.3, "Mixed

Endian Support," on page 34 for more information on this feature.

R/W

NASR

28 Direct FIFO Access Endian Ordering (FSELEND). This control bit

determines the endianess of RX and TX data FIFO host accesses when

accessed using the FIFO_SEL signal. When this bit is cleared, FIFO_SEL

accesses utilize little endian byte ordering. When this bit is set, FIFO_SEL

accesses utilize big endian byte ordering. Please refer to section Section

3.7.3, "Mixed Endian Support," on page 34 for more information on this

feature.

R/W

NASR

27-25 Reserved RO -

24 AMDIX_EN Strap State. This read-only bit reflects the state of the

AMDIX_EN strap pin (pin 73). This pin can be overridden by PHY Registers

27.15 and 27.13

RO AMDIX

Strap

23-21 Reserved RO

20 Must Be One (MBO). This bit must be set to “1” for normal device

operation.

R/W 0

16-19 TX FIFO Size (TX_FIF_SZ). Sets the size of the TX FIFOs in 1KB values

to a maximum of 14KB. The TX Status FIFO consumes 512 bytes of the

space allocated by TX_FIF_SIZ, and the TX data FIFO consumes the

remaining space specified by TX_FIF_SZ. The minimum size of the TX

FIFOs is 2KB (TX data and status combined). The TX data FIFO is used for

both TX data and TX commands.

The RX Status and data FIFOs consume the remaining space, which is

equal to 16KB – TX_FIF_SIZ. See Section 5.3.9.1, "Allowable settings for

Configurable FIFO Memory Allocation," on page 90 for more information.

R/W 5h

15-2 Reserved RO -

1Soft Reset Timeout (SRST_TO). If a software reset is attempted when the PHY

is not in the operational state (RX_CLK and TX_CLK running), the reset will not

complete and the soft reset operation will timeout and this bit will be set to a ‘1’. The

host processor must correct the problem and issue another soft reset.

RO 0

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0Soft Reset (SRST). Writing 1 generates a software initiated reset. This reset

generates a full reset of the MAC CSR’s. The SCSR’s (system command

and status registers) are reset except for any NASR bits. Soft reset also

clears any TX or RX errors (TXE/RXE). This bit is self-clearing.

Notes:

Do not attempt a soft reset unless the PHY is fully awake and operational.

After a PHY reset, or when returning from a reduced power state, the PHY

must given adequate time to return to the operational state before a soft

reset can be issued.

The LAN9221/LAN9221i must always be read at least once after power-

up, reset, or upon return from a power-saving state or write operations will

not function.

SC 0

BITS DESCRIPTION TYPE DEFAULT

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5.3.9.1 Allowable settings for Configurable FIFO Memory Allocation

TX and RX FIFO space is configurable through the CSR - HW_CFG register defined above. The user

must select the FIFO allocation by setting the TX FIFO Size (TX_FIF_SZ) field in the hardware

configuration (HW_CFG) register. The TX_FIF_SZ field selects the total allocation for the TX data path,

including the TX Status FIFO size. The TX Status FIFO size is fixed at 512 Bytes (128 TX Status

DWORDs). The TX Status FIFO length is subtracted from the total TX FIFO size with the remainder

being the TX data FIFO Size. Note that TX data FIFO space includes both commands and payload

data.

RX FIFO Size is the remainder of the unallocated FIFO space (16384 bytes – TX FIFO Size). The RX

Status FIFO size is always equal to 1/16 of the RX FIFO Size. The RX Status FIFO length is subtracted

from the total RX FIFO size with the remainder being the RX data FIFO Size.

For example, if TX_FIF_SZ = 6 then:

Total TX FIFO Size = 6144 Bytes (6KB)

TX Status FIFO Size = 512 Bytes (Fixed)

TX Data FIFO Size = 6144 – 512 = 5632 Bytes

RX FIFO Size = 16384 – 6144 = 10240 Bytes (10KB)

RX Status FIFO Size = 10240 / 16 = 640 Bytes (160 RX Status DWORDs)

RX Data FIFO Size = 10240 – 640 = 9600 Bytes

Table 5.3 shows every valid setting for the TX_FIF_SZ field. Note that settings not shown in this table

are reserved and should not be used.

Note: The RX data FIFO is considered full 4 DWORDs before the length that is specified in the

HW_CFG register.

Table 5.3 Valid TX/RX FIFO Allocations

TX_FIF_SZ

TX DATA FIFO

SIZE (BYTES)

TX STATUS FIFO

SIZE (BYTES)

RX DATA FIFO

SIZE (BYTES)

RX STATUS FIFO

SIZE (BYTES)

2 1536 512 13440 896

3 2560 512 12480 832

4 3584 512 11520 768

5 4608 512 10560 704

6 5632 512 9600 640

7 6656 512 8640 576

8 7680 512 7680 512

9 8704 512 6720 448

10 9728 512 5760 384

11 10752 512 4800 320

12 11776 512 3840 256

13 12800 512 2880 192

14 13824 512 1920 128

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In addition to the host-accessible FIFOs, the MAC Interface Layer (MIL) contains an additional 2K

bytes of TX, and 128 bytes of RX FIFO buffering. These sizes are fixed, and cannot be adjusted by

the host.

As space in the TX MIL (Mac Interface Layer) FIFO frees, data is moved into it from the TX data FIFO.

Depending on the size of the frames to be transmitted, the MIL can hold up to two Ethernet frames.

This is in addition to any TX data that may be queued in the TX data FIFO.

Conversely, as data is received by the LAN9221/LAN9221i, it is moved from the MAC to the RX MIL

FIFO, and then into the RX data FIFO. When the RX data FIFO fills up, data will continue to collect

in the RX MIL FIFO. If the RX MIL FIFO fills up and overruns, subsequent RX frames will be lost until

room is made in the RX data FIFO. For each frame of data that is lost, the RX Dropped Frames

Counter (RX_DROP) is incremented.

RX and TX MIL FIFO levels are not visible to the host processor. RX and TX MIL FIFOs operate

independent of the TX data and RX data and status FIFOs. FIFO levels set for the RX and TX data

and Status FIFOs do not take into consideration the MIL FIFOs.

5.3.10 RX_DP_CTRL—Receive Datapath Control Register

This register is used to discard unwanted receive frames.

Offset: 78h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31 RX Data FIFO Fast Forward (RX_FFWD): Writing a ‘1’ to this bit causes

the RX data FIFO to fast-forward to the start of the next frame. This bit will

remain high until the RX data FIFO fast-forward operation has completed.

No reads should be issued to the RX data FIFO while this bit is high.

Note: Please refer to section “Receive Data FIFO Fast Forward” on

page 63 for detailed information regarding the use of RX_FFWD.

R/W

30-0 Reserved RO -

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5.3.11 RX_FIFO_INF—Receive FIFO Information Register

This register contains the used space in the receive FIFOs of the LAN9221/LAN9221i Ethernet

Controller.

5.3.12 TX_FIFO_INF—Transmit FIFO Information Register

This register contains the free space in the transmit data FIFO and the used space in the transmit

status FIFO in the LAN9221/LAN9221i.

Offset: 7Ch Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31-24 Reserved RO -

23-16 RX Status FIFO Used Space (RXSUSED). Indicates the amount of space

in DWORDs, used in the RX Status FIFO.

RO 00h

15-0 RX Data FIFO Used Space (RXDUSED).). Reads the amount of space in

bytes, used in the RX data FIFO. For each receive frame, this field is

incremented by the length of the receive data rounded up to the nearest

DWORD (if the payload does not end on a DWORD boundary).

RO 0000h

Offset: 80h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31-24 Reserved RO -

23-16 TX Status FIFO Used Space (TXSUSED). Indicates the amount of space

in DWORDS used in the TX Status FIFO.

RO 00h

15-0 TX Data FIFO Free Space (TDFREE). Reads the amount of space in bytes,

available in the TX data FIFO. The application should never write more data

than is available, as indicated by this value.

RO 1200h

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5.3.13 PMT_CTRL— Power Management Control Register

This register controls the Power Management features. This register can be read while the

LAN9221/LAN9221i is in a power saving mode.

Note: The LAN9221/LAN9221i must always be read at least once after power-up, reset, or upon

return from a power-saving state or write operations will not function.

Offset: 84h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31:14 RESERVED RO -

13-12 Power Management Mode (PM_MODE) – These bits set the

LAN9221/LAN9221i into the appropriate Power Management mode. Special

care must be taken when modifying these bits.

Encoding:

00b – D0 (normal operation)

01b – D1 (wake-up frame and magic packet detection are enabled)

10b – D2 (can perform energy detect)

11b – RESERVED - Do not set in this mode

Note: When the LAN9221/LAN9221i is in any of the reduced power

modes, a write of any data to the BYTE_TEST register will wake-

up the device. DO NOT PERFORM WRITES TO OTHER

ADDRRESSES while the READY bit in this register is cleared.

SC 00b

11 RESERVED RO -

10 PHY Reset (PHY_RST) – Writing a ‘1’ to this bit resets the PHY. The internal

logic automatically holds the PHY reset for a minimum of 100us. When the

PHY is released from reset, this bit is automatically cleared. All writes to this

bit are ignored while this bit is high.

SC 0b

9Wake-On-Lan Enable (WOL_EN) – When set, the PME signal (if enabled

with PME_EN) will be asserted in accordance with the PME_IND bit upon a

WOL event. When set, the PME_INT will also be asserted upon a WOL

event, regardless of the setting of the PME_EN bit.

R/W 0b

8Energy-Detect Enable (ED_EN) - When set, the PME signal (if enabled with

PME_EN) will be asserted in accordance with the PME_IND bit upon an

Energy-Detect event. When set, the PME_INT will also be asserted upon an

Energy Detect event, regardless of the setting of the PME_EN bit.

R/W 0b

7RESERVED RO -

6PME Buffer Type (PME_TYPE) – When cleared, enables PME to function

as an open-drain buffer for use in a Wired-Or configuration. When set, the

PME output is a Push-Pull driver. When configured as an open-drain output

the PME_POL field is ignored, and the output is always active low.

R/W

NASR

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5-4 WAKE-UP Status (WUPS) – This field indicates the cause of a wake-up

event detection as follows

00b -- No wake-up event detected

01b -- Energy detected

10b -- Wake-up frame or magic packet detected

11b -- Indicates multiple events occurred

WUPS bits are cleared by writing a ‘1’ to the appropriate bit. The device must

return to the D0 state (READY bit set) before these bits can be cleared.

Note: In order to clear this bit, it is required that all event sources be

cleared as well. The event sources are described in Figure 3.18

PME and PME_INT Signal Generationon page 46.

R/WC 00

3PME indication (PME_IND). The PME signal can be configured as a pulsed

output or a static signal, which is asserted upon detection of a wake-up

event.

When set, the PME signal will pulse active for 50mS upon detection of a

wake-up event.

When clear, the PME signal is driven continuously upon detection of a wake-

up event.

The PME signal can be deactivated by clearing the WUPS bits, or by

clearing the appropriate enable (refer to Section 3.10.2.3, "Power

Management Event Indicators," on page 46).

R/W 0b

2PME Polarity (PME_POL). This bit controls the polarity of the PME signal.

When set, the PME output is an active high signal. When reset, it is active

low. When PME is configured as an open-drain output this field is ignored,

and the output is always active low.

R/W

NASR

1PME Enable (PME_EN). When set, this bit enables the external PME signal.

This bit does not affect the PME interrupt (PME_INT).

R/W 0b

0Device Ready (READY). When set, this bit indicates that

LAN9221/LAN9221i is ready to be accessed. This register can be read when

LAN9221/LAN9221i is in any power management mode. Upon waking from

any power management mode, including power-up, the host processor can

interrogate this field as an indication when LAN9221/LAN9221i has stabilized

and is fully alive. Reads and writes of any other address are invalid until this

bit is set.

Note: With the exception of HW_CFG and PMT_CTRL, read access to

any internal resources is forbidden while the READY bit is cleared.

Note: On power-up, this bit can be polled to indicate when a valid soft

reset (SRST) can be performed.

RO -

BITS DESCRIPTION TYPE DEFAULT

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5.3.14 GPIO_CFG—General Purpose IO Configuration Register

This register configures the GPIO and LED functions.

Offset: 88h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31 Reserved RO -

30:28 LED[3:1] enable (LEDx_EN). A ‘1’ sets the associated pin as an LED

output. When cleared low, the pin functions as a GPIO signal.

LED1/GPIO0 – bit 28

LED2/GPIO1 – bit 29

LED3/GPIO2 – bit 30

R/W 000

27 Reserved RO -

26:24 GPIO Interrupt Polarity 0-2 (GPIO_INT_POL). When set high, a high logic

level on the corresponding GPIO pin will set the corresponding INT_STS

pin will set the corresponding INT_STS register bit.

GPIO Interrupts must also be enabled in GPIOx_INT_EN in the INT_EN

GPIO0 – bit 24

GPIO1 – bit 25

GPIO2 – bit 26

Note: GPIO inputs must be active for greater than 40nS to be recognized

as interrupt inputs.

R/W 000

23 Reserved RO -

22:20 EEPROM Enable (EEPR_EN). The value of this field determines the

function of the external EEDIO and EECLK:

Please refer to Table 5. 4 for the EEPROM Enable bit function definitions.

Note: The host must not change the function of the EEDIO and EECLK

pins when an EEPROM read or write cycle is in progress. Do not

use reserved settings.

R/W 000

19 Reserved RO -

18:16 GPIO Buffer Type 0-2 (GPIOBUFn). When set, the output buffer for the

corresponding GPIO signal is configured as a push/pull driver. When

cleared, the corresponding GPIO set configured as an open-drain driver.

GPIO0 – bit 16

GPIO1 – bit 17

GPIO2 – bit 18

R/W 000

15:11 Reserved RO -

10:8 GPIO Direction 0-2 (GPDIRn). When set, enables the corresponding GPIO

as output. When cleared the GPIO is enabled as an input.

GPIO0 – bit 8

GPIO1 – bit 9

GPIO2 – bit 10

R/W 0000

7:5 Reserved RO -

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5.3.15 GPT_CFG-General Purpose Timer Configuration Register

This register configures the General Purpose timer. The GP Timer can be configured to generate host

interrupts at intervals defined in this register.

4:3 GPO Data 3-4 (GPODn). The value written is reflected on GPOn.

GPO3 – bit 3

GPO4 – bit 4

R/W 00

2:0 GPIO Data 0-2 (GPIODn). When enabled as an output, the value written is

reflected on GPIOn. When read, GPIOn reflects the current state of the

corresponding GPIO pin.

GPIO0 – bit 0

GPIO1 – bit 1

GPIO2 – bit 2

R/W 000

Table 5.4 EEPROM Enable Bit Definitions

[22] [21] [20] EEDIO FUNCTION EECLK FUNCTION

0 0 0 EEDIO EECLK

0 0 1 GPO3 GPO4

0 1 0 Reserved

0 1 1 GPO3 RX_DV

1 0 0 Reserved

1 0 1 TX_EN GPO4

1 1 0 TX_EN RX_DV

11 1 TX_CLK RX_CLK

Offset: 8Ch Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31-30 Reserved RO -

29 GP Timer Enable (TIMER_EN). When a one is written to this bit the GP

Timer is put into the run state. When cleared, the GP Timer is halted. On

the 1 to 0 transition of this bit the GPT_LOAD field will be preset to FFFFh.

R/W 0

28-16 Reserved RO -

15-0 General Purpose Timer Pre-Load (GPT_LOAD). This value is pre-loaded

into the GP-Timer.

R/W FFFFh

BITS DESCRIPTION TYPE DEFAULT

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5.3.16 GPT_CNT-General Purpose Timer Current Count Register

This register reflects the current value of the GP Timer.

5.3.17 WORD_SWAP—Word Swap Control

This register controls how words from the host data bus are mapped to the CSRs and Data FIFOs

inside the LAN9221/LAN9221i. The LAN9221/LAN9221i always sends data from the Transmit Data

FIFO to the network so that the low order word is sent first, and always receives data from the network

to the Receive Data FIFO so that the low order word is received first.

Offset: 90h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31-16 Reserved RO -

15-0 General Purpose Timer Current Count (GPT_CNT). This 16-bit field

reflects the current value of the GP Timer.

RO FFFFh

Offset: 98h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31:0 Word Swap. If this field is set to 00000000h, or anything except

0xFFFFFFFFh, the LAN9221/LAN9221i maps words with address bit A[1]=1

to the high order words of the CSRs and Data FIFOs, and words with

address bit A[1]=0 to the low order words of the CSRs and Data FIFOs. If

this field is set to 0xFFFFFFFFh, the LAN9221/LAN9221i maps words with

address bit A[1]=1 to the low order words of the CSRs and Data FIFOs, and

words with address bit A[1]=0 to the high order words of the CSRs and Data

FIFOs.

Note: Word swap is used in conjunction with the mixed endian

functionality to determine the final byte ordering. Refer to Section

3.7.3, "Mixed Endian Support" for more information.

R/W

NASR

00000000h

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5.3.18 FREE_RUN—Free-Run 25MHz Counter

This register reflects the value of the free-running 25MHz counter.

5.3.19 RX_DROP– Receiver Dropped Frames Counter

This register indicates the number of receive frames that have been dropped.

Offset: 9Ch Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31:0 Free Running SCLK Counter (FR_CNT):

Note: This field reflects the value of a free-running 32-bit counter. At reset

the counter starts at zero and is incremented for every 25MHz

cycle. When the maximum count has been reached the counter will

rollover. Since the bus interface is 16-bits wide, and this is a 32-bit

counter, the count value is latched on the first read. The

FREE_RUN counter can take up to 160nS to clear after a reset

event.

Note: This counter will run regardless of the power management states

D0, D1 or D2.

RO -

Offset: A0h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31-0 RX Dropped Frame Counter (RX_DFC). This counter is incremented every

time a receive frame is dropped. RX_DFC is cleared on any read of this

An interrupt can be issued when this counter passes through its halfway

point (7FFFFFFFh to 80000000h).

RC 00000000h

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5.3.20 MAC_CSR_CMD – MAC CSR Synchronizer Command Register

This register is used to control the read and write operations with the MAC CSR’s

5.3.21 MAC_CSR_DATA – MAC CSR Synchronizer Data Register

This register is used in conjunction with the MAC_CSR_CMD register to perform read and write

operations with the MAC CSR’s

Offset: A4h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31 CSR Busy. When a 1 is written into this bit, the read or write operation is

performed to the specified MAC CSR. This bit will remain set until the

operation is complete. In the case of a read this means that the host can

read valid data from the data register. The MAC_CSR_CMD and

MAC_CSR_DATA registers should not be modified until this bit is cleared.

SC 0

30 R/nW. When set, this bit indicates that the host is requesting a read

operation. When clear, the host is performing a write.

R/W 0

29-8 Reserved. RO -

7-0 CSR Address. The 8-bit value in this field selects which MAC CSR will be

accessed with the read or write operation.

R/W 00h

Offset: A8h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31-0 MAC CSR Data. Value read from or written to the MAC CSR’s. R/W 00000000h

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5.3.22 AFC_CFG – Automatic Flow Control Configuration Register

This register configures the mechanism that controls both the automatic, and software-initiated

transmission of pause frames and back pressure.

Note: The LAN9221/LAN9221i will not transmit pause frames or assert back pressure if the

transmitter is disabled.

Offset: ACh Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31:24 Reserved RO -

23:16 Automatic Flow Control High Level (AFC_HI). Specifies, in multiples of

64 bytes, the level at which flow control will trigger. When this limit is

reached the chip will apply back pressure or will transmit a pause frame as

programmed in bits [3:0] of this register.

During full-duplex operation only a single pause frame is transmitted when

this level is reached. The pause time transmitted in this frame is

programmed in the FCPT field of the FLOW register in the MAC CSR space.

During half-duplex operation each incoming frame that matches the criteria

in bits [3:0] of this register will be jammed for the period set in the

BACK_DUR field.

R/W 00h

15:8 Automatic Flow Control Low Level (AFC_LO). Specifies, in multiples of

64 bytes, the level at which a pause frame is transmitted with a pause time

setting of zero. When the amount of data in the RX data FIFO falls below

this level the pause frame is transmitted. A pause time value of zero

instructs the other transmitting device to immediately resume transmission.

The zero time pause frame will only be transmitted if the RX data FIFO had

reached the AFC_HI level and a pause frame was sent. A zero pause time

frame is sent whenever automatic flow control in enabled in bits [3:0] of this

Note: When automatic flow control is enabled the AFC_LO setting must

always be less than the AFC_HI setting.

R/W 00h

7:4 Backpressure Duration (BACK_DUR). When the LAN9221/LAN9221i

automatically asserts back pressure, it will be asserted for this period of

time. This field has no function and is not used in full-duplex mode. Please

refer to Table 5.5, describing Backpressure Duration bit mapping for more

information.

R/W 0h

3Flow Control on Multicast Frame (FCMULT). When this bit is set, the

LAN9221/LAN9221i will assert back pressure when the AFC level is

reached and a multicast frame is received. This field has no function in full-

duplex mode.

R/W 0

2Flow Control on Broadcast Frame (FCBRD). When this bit is set, the

LAN9221/LAN9221i will assert back pressure when the AFC level is

reached and a broadcast frame is received. This field has no function in full-

duplex mode.

R/W 0

1Flow Control on Address Decode (FCADD). When this bit is set, the

LAN9221/LAN9221i will assert back pressure when the AFC level is

reached and a frame addressed to the LAN9221/LAN9221i is received. This

field has no function in full-duplex mode.

R/W 0

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0Flow Control on Any Frame (FCANY). When this bit is set, the

LAN9221/LAN9221i will assert back pressure, or transmit a pause frame

when the AFC level is reached and any frame is received. Setting this bit

enables full-duplex flow control when the LAN9221/LAN9221i is operating in

full-duplex mode.

When this mode is enabled during half-duplex operation, the Flow Controller

does not decode the MAC address and will send a pause frame upon

receipt of a valid preamble (i.e., immediately at the beginning of the next

frame after the RX data FIFO level is reached).

When this mode is enabled during full-duplex operation, the Flow Controller

will immediately instruct the MAC to send a pause frame when the RX data

FIFO level is reached. The MAC will queue the pause frame transmission

for the next available window.

Setting this bit overrides bits [3:1] of this register.

R/W 0

Table 5.5 Backpressure Duration Bit Mapping

BACKPRESSURE DURATION

[19:16] 100Mbs Mode 10Mbs Mode

0h 5uS 7.2uS

1h 10uS 12.2uS

2h 15uS 17.2uS

3h 25uS 27.2uS

4h 50uS 52.2uS

5h 100uS 102.2uS

6h 150uS 152.2uS

7h 200uS 202.2uS

8h 250uS 252.2uS

9h 300uS 302.2uS

Ah 350uS 352.2uS

Bh 400uS 402.2uS

Ch 450uS 452.2uS

Dh 500uS 502.2uS

Eh 550uS 552.2uS

Fh 600uS 602.2uS

BITS DESCRIPTION TYPE DEFAULT

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5.3.23 E2P_CMD – EEPROM Command Register

This register is used to control the read and write operations with the Serial EEPROM.

Offset: B0h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31 EPC Busy: When a 1 is written into this bit, the operation specified in the

EPC command field is performed at the specified EEPROM address. This

bit will remain set until the operation is complete. In the case of a read this

means that the host can read valid data from the E2P data register. 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 remains busy until the EPC Time-out occurs. At that

time the busy bit is cleared.

Note: EPC busy will be high immediately following power-up or reset.

After the EEPROM controller has finished reading (or attempting to

read) the MAC address from the EEPROM the EPC Busy bit is

cleared.

SC 0

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30-28 EPC command. This field is used to issue commands to the EEPROM

controller. The EPC will execute commands when the EPC Busy bit is set.

A new command must not be issued until the previous command completes.

This field is encoded as follows:

READ (Read Location): This command will cause a read of the EEPROM

location pointed to by EPC Address. The result of the read is available in

the E2P_DATA register.

EWDS (Erase/Write Disable): After issued, the EEPROM will ignore erase

and write commands. To re-enable erase/write operations issue the EWEN

command.

EWEN (Erase/Write Enable): Enables the EEPROM for erase and write

operations. The EEPROM will allow erase and write operations until the

Erase/Write Disable command is sent, or until power is cycled.

Note: The EEPROM device will power-up in the erase/write-disabled

state. Any erase or write operations will fail until an Erase/Write

Enable command is issued.

WRITE (Write Location): If erase/write operations are enabled in the

EEPROM, this command will cause the contents of the E2P_DATA register

to be written to the EEPROM location selected by the EPC Address field.

WRAL (Write All): If erase/write operations are enabled in the EEPROM,

this command will cause the contents of the E2P_DATA register to be

written to every EEPROM memory location.

ERASE (Erase Location): If erase/write operations are enabled in the

EEPROM, this command will erase the location selected by the EPC

Address field.

ERAL (Erase All): If erase/write operations are enabled in the EEPROM,

this command will initiate a bulk erase of the entire EEPROM.

RELOAD (MAC Address Reload): Instructs the EEPROM controller to

reload the MAC address from the EEPROM. If a value of 0xA5 is not found

in the first address of the EEPROM, the EEPROM is assumed to be un-

programmed and MAC Address Reload operation will fail. The “MAC

Address Loaded” bit indicates a successful load of the MAC address.

R/W 0

27-10 Reserved. RO -

BITS DESCRIPTION TYPE DEFAULT

[30] [29] [28] OPERATION

00 0 READ

001 EWDS

0 1 0 EWEN

011 WRITE

100 WRAL

1 0 1 ERASE

1 1 0 ERAL

111 Reload

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5.3.24 E2P_DATA – EEPROM Data Register

This register is used in conjunction with the E2P_CMD register to perform read and write operations

with the Serial EEPROM.

9EPC Time-out. If an EEPROM operation is performed, and there is no

response from the EEPROM within 30mS, the EEPROM controller will time-

out and return to its idle state. This bit is set when a time-out occurs

indicating that the last operation was unsuccessful.

Note: If the EEDIO signal pin is externally pulled-high, EPC commands

will not time out if the EEPROM device is missing. In this case the

EPC Busy bit will be cleared as soon as the command sequence

is complete. It should also be noted that the ERASE, ERAL,

WRITE and WRAL commands are the only EPC commands that

will time-out if an EEPROM device is not present -and- the EEDIO

signal is pulled low

R/WC 0

8MAC Address Loaded. When set, this bit indicates that a valid EEPROM

was found, and that the MAC address programming has completed

normally. This bit is set after a successful load of the MAC address after

power-up, or after a RELOAD command has completed

R/WC -

7-0 EPC Address. The 8-bit value in this field is used by the EEPROM

Controller to address the specific memory location in the Serial EEPROM.

This is a Byte aligned address.

R/W 00h

Offset: B4h Size: 32 bits

BITS DESCRIPTION TYPE DEFAULT

31-8 Reserved RO -

7:0 EEPROM Data. Value read from or written to the EEPROM. R/W 00h

BITS DESCRIPTION TYPE DEFAULT

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5.4 MAC Control and Status Registers

These registers are located in the MAC module and are accessed indirectly through the MAC-CSR

synchronizer port. Table 5.6, "MAC CSR Register Map", shown below, lists the MAC registers that are

accessible through the indexing method using the MAC_CSR_CMD and MAC_CSR_DATA registers

(see sections MAC_CSR_CMD – MAC CSR Synchronizer Command Register and MAC_CSR_DATA

– MAC CSR Synchronizer Data Register).

Table 5.6 MAC CSR Register Map

MAC CONTROL AND STATUS REGISTERS

INDEX SYMBOL REGISTER NAME DEFAULT

1MAC_CR

MAC Control Register 00040000h

2 ADDRH MAC Address High 0000FFFFh

3 ADDRL MAC Address Low FFFFFFFFh

4 HASHH Multicast Hash Table High 00000000h

5 HASHL Multicast Hash Table Low 00000000h

6MII_ACC

MII Access 00000000h

7 MII_DATA MII Data 00000000h

8FLOW

Flow Control 00000000h

9VLAN1

VLAN1 Tag 00000000h

AVLAN2

VLAN2 Tag 00000000h

BWUFF

Wake-up Frame Filter 00000000h

CWUCSR

Wake-up Control and Status 00000000h

DCOE_CR

Checksum Offload Engine Control 00000000h

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5.4.1 MAC_CR—MAC Control Register

This register establishes the RX and TX operation modes and controls for address filtering and packet

filtering.

Offset: 1 Attribute: R/W

Default Value: 00040000h Size: 32 bits

BITS DESCRIPTION

31 Receive All Mode (RXALL). When set, all incoming packets will be received and passed on to the

address filtering Function for processing of the selected filtering mode on the received frame. Address

filtering then occurs and is reported in Receive Status. When reset, only frames that pass Destination

Address filtering will be sent to the Application.

30-24 Reserved

23 Disable Receive Own (RCVOWN). When set, the MAC disables the reception of frames when the

MII TX_EN signal is asserted. The MAC blocks the transmitted frame on the receive path. When reset,

the MAC receives all packets the PHY gives, including those transmitted by the MAC.This bit should

be reset when the Full Duplex Mode bit is set.

22 Reserved

21 Loopback operation Mode (LOOPBK). Selects the loop back operation modes for the MAC. This is

only for full duplex mode

1’b0: Normal: No feedback

1’b1: Internal: Through MII

In internal loopback mode, the TX frame is received by the Internal MII interface, and sent back to

the MAC without being sent to the PHY.

Note: When enabling or disabling the loopback mode it can take up to 10μs for the mode change

to occur. The transmitter and receiver must be stopped and disabled when modifying the

LOOPBK bit. The transmitter or receiver should not be enabled within10μs of modifying the

LOOPBK bit.

20 Full Duplex Mode (FDPX). When set, the MAC operates in Full-Duplex mode, in which it can transmit

and receive simultaneously. In Full-Duplex mode, the heartbeat check is disabled and the heartbeat

fail status should thus be ignored.

19 Pass All Multicast (MCPAS). When set, indicates that all incoming frames with a Multicast destination

address (first bit in the destination address field is 1) are received. Incoming frames with physical

address (Individual Address/Unicast) destinations are filtered and received only if the address matches

the MAC Address.

18 Promiscuous Mode (PRMS). When set, indicates that any incoming frame is received regardless of

its destination address.

17 Inverse filtering (INVFILT). When set, the address check Function operates in Inverse filtering mode.

This is valid only during Perfect filtering mode.

16 Pass Bad Frames (PASSBAD). When set, all incoming frames that passed address filtering are

received, including runt frames and collided frames.

15 Hash Only Filtering mode (HO). When set, the address check Function operates in the Imperfect

Address Filtering mode both for physical and multicast addresses

14 Reserved

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13 Hash/Perfect Filtering Mode (HPFILT). When reset (0), the LAN9221/LAN9221i will implement a

perfect address filter on incoming frames according the address specified in the MAC address register.

When set (1), the address check Function does imperfect address filtering of multicast incoming

frames according to the hash table specified in the multicast hash table register.

If the Hash Only Filtering mode (HO) bit is set (1), then the physical (IA) are imperfect filtered too. If

the Hash Only Filtering mode (HO) bit is reset (0), then the IA addresses are perfect address filtered

according to the MAC Address register

12 Late Collision Control (LCOLL). When set, enables retransmission of the collided frame even after

the collision period (late collision). When reset, the MAC disables frame transmission on a late

collision. In any case, the Late Collision status is appropriately updated in the Transmit Packet status.

11 Disable Broadcast Frames (BCAST). When set, disables the reception of broadcast frames. When

reset, forwards all broadcast frames to the application.

Note: When wake-up frame detection is enabled via the WUEN bit of the WUCSR—Wake-up

Control and Status Register, a broadcast wake-up frame will wake-up the device despite the

state of this bit.

10 Disable Retry (DISRTY). When set, the MAC attempts only one transmission. When a collision is

seen on the bus, the MAC ignores the current frame and goes to the next frame and a retry error is

reported in the Transmit status. When reset, the MAC attempts 16 transmissions before signaling a

retry error.

9Reserved

8Automatic Pad Stripping (PADSTR). When set, the MAC strips the pad field on all incoming frames,

if the length field is less than 46 bytes. The FCS field is also stripped, since it is computed at the

transmitting station based on the data and pad field characters, and is invalid for a received frame

that has had the pad characters stripped. Receive frames with a 46-byte or greater length field are

passed to the Application unmodified (FCS is not stripped). When reset, the MAC passes all incoming

frames to the host unmodified.

Note: When PADSTR is enabled, the RX Checksum Offload Engine must be disabled (bit 0

(RXCOE_EN) of the COE_CR—Checksum Offload Engine Control Register) and vice versa.

These functions cannot be enabled simultaneously.

BITS DESCRIPTION

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7-6 BackOff Limit (BOLMT). The BOLMT bits allow the user to set its back-off limit in a relaxed or

aggressive mode. According to IEEE 802.3, the MAC has to wait for a random number [r] of slot-

times** after it detects a collision, where:

(eq.1)0 < r < 2K

The exponent K is dependent on how many times the current frame to be transmitted has been retried,

as follows:

(eq.2)K = min (n, 10) where n is the current number of retries.

If a frame has been retried three times, then K = 3 and r= 8 slot-times maximum. If it has been retried

12 times, then K = 10, and r = 1024 slot-times maximum.

An LFSR (linear feedback shift register) 20-bit counter emulates a 20bit random number generator,

from which r is obtained. Once a collision is detected, the number of the current retry of the current

frame is used to obtain K (eq.2). This value of K translates into the number of bits to use from the

LFSR counter. If the value of K is 3, the MAC takes the value in the first three bits of the LFSR counter

and uses it to count down to zero on every slot-time. This effectively causes the MAC to wait eight

slot-times. To give the user more flexibility, the BOLMT value forces the number of bits to be used

from the LFSR counter to a predetermined value as in the table below.

Thus, if the value of K = 10, the MAC will look at the BOLMT if it is 00, then use the lower ten bits of the LFSR

counter for the wait countdown. If the BOLMT is 10, then it will only use the value in the first four bits for the

wait countdown, etc.

**Slot-time = 512 bit times. (See IEEE 802.3 Spec., Secs. 4.2.3.25 and 4.4.2.1)

5Deferral Check (DFCHK). When set, enables the deferral check in the MAC. The MAC will abort the

transmission attempt if it has deferred for more than 24,288 bit times. Deferral starts when the

transmitter is ready to transmit, but is prevented from doing so because the CRS is active. Defer time

is not cumulative. If the transmitter defers for 10,000 bit times, then transmits, collides, backs off, and

then has to defer again after completion of back-off, the deferral timer resets to 0 and restarts. When

reset, the deferral check is disabled in the MAC and the MAC defers indefinitely.

4Reserved

3Transmitter enable (TXEN). When set, the MAC’s transmitter is enabled and it will transmit frames

from the buffer onto the cable.

When reset, the MAC’s transmitter is disabled and will not transmit any frames.

2Receiver Enable (RXEN). When set (1), the MAC’s receiver is enabled and will receive frames from

the internal PHY.

When reset, the MAC’s receiver is disabled and will not receive any frames from the internal PHY.

1-0 Reserved

BITS DESCRIPTION

BOLMT Value # Bits Used from LFSR Counter

2’b00 10

2’b01 8

2’b10 4

2’b11 1

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5.4.2 ADDRH—MAC Address High Register

The MAC Address High register contains the upper 16-bits of the physical address of the MAC. The

contents of this register are optionally loaded from the EEPROM at power-on through the EEPROM

Controller if a programmed EEPROM is detected. The least significant byte of this register (bits [7:0])

is loaded from address 0x05 of the EEPROM. The second byte (bits [15:8]) is loaded from address

0x06 of the EEPROM. Please refer to Section 4.6 for more information on the EEPROM. Section 5.4.3

details the byte ordering of the ADDRL and ADDRH registers with respect to the reception of the

Ethernet physical address.

Offset: 2 Attribute: R/W

Default Value: 0000FFFFh Size: 32 bits

BITS DESCRIPTION

31-16 Reserved

15-0 Physical Address [47:32]. This field contains the upper 16-bits (47:32) of the Physical Address of

the LAN9221/LAN9221i device. The content of this field is undefined until loaded from the EEPROM

at power-on. The host can update the contents of this field after the initialization process has

completed.

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5.4.3 ADDRL—MAC Address Low Register

The MAC Address Low register contains the lower 32 bits of the physical address of the MAC. The

contents of this register are optionally loaded from the EEPROM at power-on through the EEPROM

Controller if a programmed EEPROM is detected. The least significant byte of this register (bits [7:0])

is loaded from address 0x01 of the EEPROM. The most significant byte of this register is loaded from

address 0x04 of the EEPROM. Please refer to Section 4.6 for more information on the EEPROM.

Table 5.7 below illustrates the byte ordering of the ADDRL and ADDRH registers with respect to the

reception of the Ethernet physical address. Also shown is the correlation between the EEPROM

addresses and ADDRL and ADDRH registers.

As an example, if the desired Ethernet physical address is 12-34-56-78-9A-BC, the ADDRL and

ADDRH registers would be programmed as shown in Figure 5.2. The values required to automatically

load this configuration from the EEPROM are also shown.

Figure 5.2 Example ADDRL, ADDRH and EEPROM Setup

Offset: 3 Attribute: R/W

Default Value: FFFFFFFFh Size: 32 bits

BITS DESCRIPTION

31-0 Physical Address [31:0]. This field contains the lower 32 bits (31:0) of the Physical Address of the

LAN9221/LAN9221i device. The content of this field is undefined until loaded from the EEPROM at

power-on. The host can update the contents of this field after the initialization process has completed.

Table 5.7 ADDRL, ADDRH and EEPROM Byte Ordering

EEPROM ADDRESS ADDRN

ORDER OF RECEPTION ON

ETHERNET

0x01 ADDRL[7:0] 1st

0x02 ADDRL[15:8] 2nd

0x03 ADDRL[23:16] 3rd

0x04 ADDRL[31:24] 4th

0x05 ADDRH[7:0] 5th

0x06 ADDRH[15:8] 6th

0x12

0x34

815

0x56

1623

0x78

2431

ADDRL

0x9A

0xBC

815

ADDRH

1623

2431

0xA5

0x12

0x34

0x56

0x78

0x9A

0xBC

0x00

0x01

0x02

0x03

0x04

0x05

0x06

EEPROM

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Note: By convention, the left most byte of the Ethernet address (in this example 0x12) is the most

significant byte and is transmitted/received first.

5.4.4 HASHH—Multicast Hash Table High Register

The 64-bit Multicast table is used for group address filtering. For hash filtering, the contents of the

destination address in the incoming frame is used to index the contents of the Hash table. The most

significant bit determines the register to be used (Hi/Low), while the other five bits determine the bit

within the register. A value of 00000 selects Bit 0 of the Multicast Hash Table Lo register and a value

of 11111 selects the Bit 31 of the Multicast Hash Table Hi register.

If the corresponding bit is 1, then the multicast frame is accepted. Otherwise, it is rejected. If the “Pass All

Multicast” (MCPAS) bit is set (1), then all multicast frames are accepted regardless of the multicast hash

values.

The Multicast Hash Table Hi register contains the higher 32 bits of the hash table and the Multicast

Hash Table Low register contains the lower 32 bits of the hash table.

5.4.5 HASHL—Multicast Hash Table Low Register

This register defines the lower 32-bits of the Multicast Hash Table. Please refer to Table 5.4.4,

"HASHH—Multicast Hash Table High Register" for further details.

Offset: 4 Attribute: R/W

Default Value: 00000000h Size: 32 bits

BITS DESCRIPTION

31-0 Upper 32 bits of the 64-bit Hash Table

Offset: 5 Attribute: R/W

Default Value: 00000000h Size: 32 bits

BITS DESCRIPTION

31-0 Lower 32 bits of the 64-bit Hash Table

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5.4.6 MII_ACC—MII Access Register

This register is used to control the Management cycles to the PHY.

5.4.7 MII_DATA—MII Data Register

This register contains either the data to be written to the PHY register specified in the MII Access

Offset: 6 Attribute: R/W

Default Value: 00000000h Size: 32 bits

BITS DESCRIPTION

31-16 Reserved

15-11 PHY Address: For every access to this register, this field must be set to 00001b.

10-6 MII Register Index (MIIRINDA): These bits select the desired MII register in the PHY.

5-2 Reserved

1MII Write (MIIWnR): Setting this bit tells the PHY that this will be a write operation using the MII data

0MII Busy (MIIBZY): This bit must be polled to determine when the MII register access is complete.

This bit must read a logical 0 before writing to this register and MII data register.

The LAN driver software must set (1) this bit in order for the LAN9221/LAN9221i to read or write any

of the MII PHY registers.

During a MII register access, this bit will be set, signifying a read or write access is in progress. The

MII data register must be kept valid until the MAC clears this bit during a PHY write operation. The

MII data register is invalid until the MAC has cleared this bit during a PHY read operation.

Offset: 7 Attribute: R/W

Default Value: 00000000h Size: 32 bits

BITS DESCRIPTION

31-16 Reserved

15-0 MII Data. This contains the 16-bit value read from the PHY read operation or the 16-bit data value to

be written to the PHY before an MII write operation.

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5.4.8 FLOW—Flow Control Register

This register controls the generation and reception of the Control (Pause command) frames by the

MAC’s flow control block. The control frame fields are selected as specified in the 802.3x Specification

and the Pause-Time value from this register is used in the “Pause Time” field of the control frame. In

full-duplex mode the FCBSY bit is set until the control frame is transferred onto the cable. In half-

duplex mode FCBSY is set while back pressure is being asserted. The host has to make sure that the

Busy bit is cleared before writing the register. The Pass Control Frame bit (FCPASS) does not affect

the sending of the frames, including Control Frames, to the Application Interface. The Flow Control

Enable (FCEN) bit enables the receive portion of the Flow Control block.

This register is used in conjunction with the AFC_CFG register in the Slave CSRs to configure flow

control. Software flow control is initiated using the AFC_CFG register.

Note: The LAN9221/LAN9221i will not transmit pause frames or assert back pressure if the

transmitter is disabled.

Offset: 8 Attribute: R/W

Default Value: 00000000h Size: 32 bits

BITS DESCRIPTION

31-16 Pause Time (FCPT). This field indicates the value to be used in the PAUSE TIME field in the control

frame. This field must be initialized before full-duplex automatic flow control is enabled.

15-3 Reserved

2Pass Control Frames (FCPASS). When set, the MAC will pass the pause frame to the host. The

Application must accept or discard a received frame based on the Packet Filter control bit. The MAC

receives, decodes and performs the Pause function when a valid Pause frame is received in Full-

Duplex mode and when flow control is enabled (FCE bit set). When reset, the MAC resets the Packet

Filter bit in the Receive packet status.

The MAC always passes the data of all frames it receives (including Flow Control frames) to the

Application. Frames that do not pass Address filtering, as well as frames with errors, are passed to

the Application. The Application must discard or retain the received frame’s data based on the

received frame’s STATUS field. Filtering modes (Promiscuous mode, for example) take precedence

over the FCPASS bit.

1Flow Control Enable (FCEN). When set, enables the MAC Flow Control function. The MAC decodes

all incoming frames for control frames; if it receives a valid control frame (PAUSE command), it

disables the transmitter for a specified time (Decoded pause time x slot time). When reset, the MAC

flow control function is disabled; the MAC does not decode frames for control frames.

Note: Flow Control is applicable when the MAC is set in Full Duplex Mode. In Half-Duplex mode,

this bit enables the Backpressure function to control the flow of received frames to the MAC.

0Flow Control Busy (FCBSY). This bit is set high whenever a pause frame or back pressure is being

transmitted. This bit should read logical 0 before writing to the Flow Control (FLOW) register. During

a transfer of Control Frame, this bit continues to be set, signifying that a frame transmission is in

progress. After the PAUSE control frame’s transmission is complete, the MAC resets to 0.

Notes:

When writing this register the FCBSY bit must always be zero.

Applications must always write a zero to this bit

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5.4.9 VLAN1—VLAN1 Tag Register

This register contains the VLAN tag field to identify VLAN1 frames. For VLAN frames the legal frame

length is increased from 1518 bytes to 1522 bytes.

5.4.10 VLAN2—VLAN2 Tag Register

This register contains the VLAN tag field to identify VLAN2 frames. For VLAN frames the legal frame

length is increased from 1518 bytes to 1522 bytes.

Offset: 9 Attribute: R/W

Default Value: 00000000h Size: 32 bits

BITS DESCRIPTION

31-16 Reserved

15-0 VLAN1 Tag Identifier (VTI1). This contains the VLAN Tag field to identify the VLAN1 frames. This

field is compared with the 13th and 14th bytes of the incoming frames for VLAN1 frame detection.

If used, this register must be set to 0x8100.

Offset: A Attribute: R/W

Default Value: 00000000h Size: 32 bits

BITS DESCRIPTION

31-16 Reserved

15-0 VLAN2 Tag Identifier (VTI2). This contains the VLAN Tag field to identify the VLAN2 frames. This

field is compared with the 13th and 14th bytes of the incoming frames for VLAN2 frame detection.If

used, this register must be set to 0x8100.

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5.4.11 WUFF—Wake-up Frame Filter

This register is used to configure the wake up frame filter.

5.4.12 WUCSR—Wake-up Control and Status Register

This register contains data pertaining to the MAC’s remote wake-up status and capabilities.

Offset: B Attribute: WO

Default Value: 00000000h Size: 32 bits

BITS DESCRIPTION

31-0 Wake-Up Frame Filter (WFF). Wake-Up Frame Filter (WFF). The Wake-up frame filter is configured

through this register using an indexing mechanism. After hardware reset, or soft reset, the MAC loads

the first value written to this location to the first DWORD in the Wake-up frame filter (filter 0 byte

mask). The second value written to this location is loaded to the second DWORD in the wake-up

frame filter (filter 1 byte mask) and so on. Once all eight DWORDs have been written, the internal

pointer will once again point to the first entry and the filter entries can be modified in the same manner.

Note: This is a write-only register.

Offset: C Attribute: R/W

Default Value: 00000000h Size: 32 bits

BITS DESCRIPTION

31-10 Reserved

9Global Unicast Enable (GUE). When set, the MAC wakes up from power-saving mode on receipt of

a global unicast frame. A global unicast frame has the MAC Address [0] bit set to 0.

8-7 Reserved

6Remote Wake-Up Frame Received (WUFR). The MAC, upon receiving a valid Remote Wake-up

frame, sets this bit.

5Magic Packet Received (MPR). The MAC, upon receiving a valid Magic Packet, sets this bit.

4-3 Reserved

2Wake-Up Frame enabled (WUEN). When set, Remote Wake-Up mode is enabled and the MAC is

capable of detecting wake-up frames as programmed in the wake-up frame filter.

1Magic Packet Enable (MPEN). When set, Magic Packet Wake-up mode is enabled.

0Reserved

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5.4.13 COE_CR—Checksum Offload Engine Control Register

This register controls the transmit and receive checksum offload engines.

Offset: D Attribute: R/W

Default Value: 00000000h Size: 32 bits

BITS DESCRIPTION

31-17 Reserved

16 TX Checksum Offload Engine Enable (TXCOE_EN). This bit enables/disables the Transmit COE.

This bit may only be changed if the TX data path is disabled.

0: The TXCOE is bypassed

1: The TXCOE is enabled

15-2 Reserved

1RX Checksum Offload Engine Mode (RXCOE_MODE) This register indicates whether the RXCOE

will check for VLAN tags or a SNAP header prior to beginning its checksum calculation. In its default

mode, the calculation will always begin 14 bytes into the frame.

The RXCOE_MODE may only be changed if the ESS RX path is disabled.

0: Begin checksum calculation after first 14 bytes of Ethernet Frame

1: Begin checksum calculation at start of L3 packet by adjusting for VLAN tags and/or SNAP header.

0RX Checksum Offload Engine Enable (RXCOE_EN). This bit enables/disables the Receive COE.

This bit may only be changed if the RX data path is disabled.

0: The RXCOE is bypassed

1: The RXCOE is enabled

Note: When the RXCOE is enabled, automatic pad stripping must be disabled (bit 8 (PADSTR) of

the MAC_CR—MAC Control Register) and vice versa. These functions cannot be enabled

simultaneously.

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5.5 PHY Registers

The PHY registers are not memory mapped. These registers are accessed indirectly through the MAC

via the MII_ACC and MII_DATA registers. An index must be used to access individual PHY registers.

PHY Register Indexes are shown in Table 5.8, "LAN9221/LAN9221i PHY Control and Status Register".

Note: The NASR (Not Affected by Software Reset) designation is only applicable when bit 15 of

the PHY Basic Control Register (Reset) is set.

Table 5.8 LAN9221/LAN9221i PHY Control and Status Register

PHY CONTROL AND STATUS REGISTERS

INDEX

(IN DECIMAL) REGISTER NAME

0Basic Control Register

1Basic Status Register

2PHY Identifier 1

3PHY Identifier 2

4Auto-Negotiation Advertisement Register

5Auto-Negotiation Link Partner Ability Register

6Auto-Negotiation Expansion Register

17 Mode Control/Status Register

18 Special Modes Register

27 Special Control/Status Indications

29 Interrupt Source Register

30 Interrupt Mask Register

31 PHY Special Control/Status Register

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5.5.1 Basic Control Register

Note 5.1 The default value of this bit is determined by the auto-negotiation process.

Index (In Decimal): 0 Size: 16-bits

BITS DESCRIPTION TYPE DEFAULT

15 Reset. 1 = software reset. Bit is self-clearing. For best results, when setting

this bit do not set other bits in this register.

RW/SC 0

14 Loopback. 1 = loopback mode, 0 = normal operation RW 0

13 Speed Select. 1 = 100Mbps, 0 = 10Mbps. Ignored if Auto Negotiation is

enabled (0.12 = 1).

RW See Note 5.1

12 Auto-Negotiation Enable. 1 = enable auto-negotiate process (overrides

0.13 and 0.8) 0 = disable auto-negotiate process.

RW 1

11 Power Down. 1 = General power down-mode, 0 = normal operation.

Note: After this bit is cleared, the PHY may auto-negotiate with it's

partner station. This process may take a few seconds to complete.

Once auto-negotiation is complete, bit 5 of the PHY's Basic Status

RW 0

10 Reserved RO 0

9Restart Auto-Negotiate. 1 = restart auto-negotiate process 0 = normal

operation. Bit is self-clearing.

RW/SC 0

8Duplex Mode. 1 = full duplex, 0 = half duplex. Ignored if Auto Negotiation

is enabled (0.12 = 1).

RW See Note 5.1

7Collision Test. 1 = enable COL test, 0 = disable COL test RW 0

6-0 Reserved RO 0

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5.5.2 Basic Status Register

5.5.3 PHY Identifier 1

Index (In Decimal): 1 Size: 16-bits

BITS DESCRIPTION TYPE DEFAULT

15 100Base-T4. 1 = T4 able, 0 = no T4 ability RO 0

14 100Base-TX Full Duplex. 1 = TX with full duplex, 0 = no TX full duplex

ability.

RO 1

13 100Base-TX Half Duplex. 1 = TX with half duplex, 0 = no TX half duplex

ability.

RO 1

12 10Base-T Full Duplex. 1 = 10Mbps with full duplex 0 = no 10Mbps with full

duplex ability

RO 1

11 10Base-T Half Duplex. 1 = 10Mbps with half duplex 0 = no 10Mbps with

half duplex ability

RO 1

10-6 Reserved RO 0

5Auto-Negotiate Complete. 1 = auto-negotiate process completed 0 = auto-

negotiate process not completed

RO 0

4Remote Fault. 1 = remote fault condition detected 0 = no remote fault RO/LH 0

3Auto-Negotiate Ability. 1 = able to perform auto-negotiation function 0 =

unable to perform auto-negotiation function

RO 1

2Link Status. 1 = link is up, 0 = link is down RO/LL 0

1Jabber Detect. 1 = jabber condition detected 0 = no jabber condition

detected

RO/LH 0

0Extended Capabilities. 1 = supports extended capabilities registers 0 =

does not support extended capabilities registers.

RO 1

Index (In Decimal): 2 Size: 16-bits

BITS DESCRIPTION TYPE DEFAULT

15-0 PHY ID Number. Assigned to the 3rd through 18th bits of the

Organizationally Unique Identifier (OUI), respectively.

RO 0x0007h

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5.5.4 PHY Identifier 2

5.5.5 Auto-negotiation Advertisement

Note 5.2 When both symmetric PAUSE and asymmetric PAUSE support are advertised (value of

11), the device will only be configured to, at most, one of the two settings upon auto-

negotiation completion.

Index (In Decimal): 3 Size: 16-bits

BITS DESCRIPTION TYPE DEFAULT

15-10 PHY ID Number Assigned to the 19th through 24th bits of the OUI. RO 0xC0C3h

9 - 4 Model Number. Six-bit manufacturer’s model number. RO

3 - 0 Revision Number. Four-bit manufacturer’s revision number. RO

Index (In Decimal): 4 Size: 16-bits

BITS DESCRIPTION TYPE DEFAULT

15:14 Reserved RO 00

13 Remote Fault. 1 = remote fault detected, 0 = no remote fault R/W 0

12 Reserved R/W 0

11:10 Pause Operation. (See Note 5.2)

00 No PAUSE

01 Symmetric PAUSE

10 Asymmetric PAUSE

11 Advertise support for both Symmetric PAUSE and Asymmetric PAUSE

R/W 00

9Reserved RO 0

8100Base-TX Full Duplex. 1 = TX with full duplex, 0 = no TX full duplex

ability

R/W 1

7100Base-TX. 1 = TX able, 0 = no TX ability R/W 1

610Base-T Full Duplex.

1 = 10Mbps with full duplex

0 = no 10Mbps with full duplex ability

R/W 1

510Base-T. 1 = 10Mbps able, 0 = no 10Mbps ability R/W 1

4:0 Selector Field. [00001] = IEEE 802.3 R/W 00001

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5.5.6 Auto-negotiation Link Partner Ability

Index (In Decimal): 5 Size: 16-bits

BITS DESCRIPTION TYPE DEFAULT

15 Next Page. 1 = next page capable, 0 = no next page ability. This device

does not support next page ability.

RO 0

14 Acknowledge. 1 = link code word received from partner 0 = link code word

not yet received

Note: This bit will always read 0

RO 0

13 Remote Fault. 1 = remote fault detected, 0 = no remote fault RO 0

12 Reserved RO 0

11-10 Pause Operation.

00 No PAUSE supported by partner station

01 Symmetric PAUSE supported by partner station

10 Asymmetric PAUSE supported by partner station

11 Both Symmetric PAUSE and Asymmetric PAUSE supported by partner

station

RO 00

9100Base-T4. 1 = T4 able, 0 = no T4 ability RO 0

8100Base-TX Full Duplex. 1 = TX with full duplex, 0 = no TX full duplex

ability

RO 0

7100Base-TX. 1 = TX able, 0 = no TX ability RO 0

610Base-T Full Duplex.

1 = 10Mbps with full duplex

0 = no 10Mbps with full duplex ability

RO 0

510Base-T. 1 = 10Mbps able, 0 = no 10Mbps ability RO 0

4:0 Selector Field. [00001] = IEEE 802.3 RO 00001

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5.5.7 Auto-negotiation Expansion

5.5.8 Mode Control/Status

Note 5.3 The default value of this bit will vary dependant on the current link state of the line.

Index (In Decimal): 6 Size: 16-bits

BITS DESCRIPTION TYPE DEFAULT

15:5 Reserved RO 0

4Parallel Detection Fault.

1 = fault detected by parallel detection logic

0 = no fault detected by parallel detection logic

RO/LH 0

3Link Partner Next Page Able.

1 = link partner has next page ability

0 = link partner does not have next page ability

RO 0

2Next Page Able.

1 = local device has next page ability

0 = local device does not have next page ability

RO 0

1Page Received.

1 = new page received

0 = new page not yet received

RO/LH 0

0Link Partner Auto-Negotiation Able.

1 = link partner has auto-negotiation ability

0 = link partner does not have auto-negotiation ability

RO 0

Index (In Decimal): 17 Size: 16-bits

BITS DESCRIPTION TYPE DEFAULT

15-14 Reserved. Write as 0; ignore on read. RW 0

13 EDPWRDOWN. Enable the Energy Detect Power-Down mode:

0=Energy Detect Power-Down is disabled

1=Energy Detect Power-Down is enabled

RW 0

12-2 Reserved. Write as 0, ignore on read RW 0

1ENERGYON. Indicates whether energy is detected. This bit goes to a “0” if

no valid energy is detected within 256ms. Reset to “1” by hardware reset,

unaffected by SW reset.

RO See Note 5.3

0Reserved. Write as “0”. Ignore on read. RW 0

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5.5.9 Special Modes

Note 5.4 When MODE=111, the register 0 bits 13 and 8 are variable dependant on the auto-

negotiated speed and duplex.

Index (In Decimal): 18 Size: 16-bits

ADDRESS DESCRIPTION TYPE DEFAULT

15-8 Reserved RW,

NASR

7:5 MODE: PHY Mode of operation. Refer to Table 5.9 for more details. RW,

NASR

111

4:0 PHYAD: PHY Address:

The PHY Address is used for the SMI address.

RW,

NASR

00001b

Table 5.9 MODE Control

MODE MODE DEFINITIONS

DEFAULT REGISTER BIT VALUES

[13,12,10,8] [8,7,6,5]

000 10Base-T Half Duplex. Auto-negotiation disabled. 0000 N/A

001 10Base-T Full Duplex. Auto-negotiation disabled. 0001 N/A

010 100Base-TX Half Duplex. Auto-negotiation disabled.

CRS is active during Transmit & Receive.

1000 N/A

011 100Base-TX Full Duplex. Auto-negotiation disabled.

CRS is active during Receive.

1001 N/A

100 100ase-TX Half Duplex is advertised. Auto-

negotiation enabled.

CRS is active during Transmit & Receive.

1100 0100

101 Repeater mode. Auto-negotiation enabled.

100Base-TX Half Duplex is advertised.

CRS is active during Receive.

1100 0100

110 Reserved - Do not set the LAN9221/LAN9221i in

this mode.

N/A N/A

111 All capable. Auto-negotiation enabled. X10X

Note 5.4

1111

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5.5.10 Special Control/Status Indications

Index (In Decimal): 27 Size: 16-bits

ADDRESS DESCRIPTION MODE DEFAULT

15 Override AMDIX Strap

0 - AMDIX_EN (pin 52) enables or disables HP Auto MDIX

1 - Override pin 52. PHY Register 27.14 and 27.13 determine MDIX

function

RW 0

14 Auto-MDIX Enable: Only effective when 27.15=1, otherwise ignored.

0 = Disable Auto-MDIX. 27.13 determines normal or reversed connection.

1 = Enable Auto-MDIX. 27.13 must be set to 0.

RW 0

13 Auto-MDIX State. Only effective when 27.15=1, otherwise ignored.

When 27.14 = 0 (manually set MDIX state):

0 = no crossover (TPO = output, TPI = input)

1 = crossover (TPO = input, TPI = output)

When 27.14 = 1 (automatic MDIX) this bit must be set to 0.

Do not use the combination 27.15=1, 27.14=1, 27.13=1.

RW 0

12:11 Reserved: Write as 0. Ignore on read. RW 0

10 VCOOFF_LP: Forces the Receive PLL 10M to lock on the reference clock

at all times:

0 - Receive PLL 10M can lock on reference or line as needed (normal

operation)

1 - Receive PLL 10M is locked on the reference clock.

In this mode 10M data packets cannot be received.

RW,

NASR

9-5 Reserved: Write as 0. Ignore on read. RW 0

4XPOL: Polarity state of the 10Base-T:

0 - Normal polarity

1 - Reversed polarity

RO 0

3:0 Reserved: Read only - Writing to these bits have no effect. RO XXXXb

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5.5.11 Interrupt Source Flag

Note 5.5 The default value of this bit will vary dependant on the current link state of the line.

5.5.12 Interrupt Mask

Index (In Decimal): 29 Size: 16-bits

BITS DESCRIPTION TYPE DEFAULT

15-8 Reserved. Ignore on read. RO/LH 0

7INT7. 1= ENERGYON generated, 0= not source of interrupt RO/LH 0

6INT6. 1= Auto-Negotiation complete, 0= not source of interrupt RO/LH 0

5INT5. 1= Remote Fault Detected, 0= not source of interrupt RO/LH 0

4INT4. 1= Link Down (link status negated), 0= not source of interrupt RO/LH See Note 5.5

3INT3. 1= Auto-Negotiation LP Acknowledge, 0= not source of interrupt RO/LH 0

2INT2. 1= Parallel Detection Fault, 0= not source of interrupt RO/LH 0

1INT1. 1= Auto-Negotiation Page Received, 0= not source of interrupt RO/LH 0

0Reserved. RO/LH 0

Index (In Decimal): 30 Size: 16-bits

BITS DESCRIPTION TYPE DEFAULT

15-8 Reserved. Write as 0; ignore on read. RO 0

7-0 Mask Bits. 1 = interrupt source is enabled 0 = interrupt source is masked RW 0

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5.5.13 PHY Special Control/Status

Note 5.6 The default value of this bit is determined by the auto-negotiation process.

Index (In Decimal): 31 Size: 16-bits

BITS DESCRIPTION TYPE DEFAULT

15 - 13 Reserved RO 000b

12 Autodone. Auto-negotiation done indication:

0 = Auto-negotiation is not done or disabled (or not active)

1 = Auto-negotiation is done

RO 0b

11-5 Reserved. Write as 0000010b, ignore on Read. RW 0000010b

4-2 Speed Indication. HCDSPEED value:

[001]=10Mbps half-duplex

[101]=10Mbps full-duplex

[010]=100Base-TX half-duplex

[110]=100Base-TX full-duplex

RO See Note 5.6

1-0 Reserved. Write as 0; ignore on Read RO 00b

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Chapter 6 Timing Diagrams

6.1 Equivalent Test Load

Output timing specifications assume an equivalent test load as illustrated in Figure 6.1 below.

6.2 Host Interface Timing

The LAN9221/LAN9221i supports the following host cycles:

Read Cycles:

PIO Reads (nCS or nRD controlled)

PIO Burst Reads (nCS or nRD controlled)

RX Data FIFO Direct PIO Reads (nCS or nRD controlled)

RX Data FIFO Direct PIO Burst Reads (nCS or nRD controlled)

Write Cycles:

PIO writes (nCS and nWR controlled)

TX Data FIFO direct PIO writes (nCS or nWR controlled)

All timing measurements were verified under the following conditions:

Note: The specified test load used for output timing is dependant on VDDVARIO.

Temperature: ................................................................................................................................ Note 6.1

Load Capacitance (VDDVARIO = 3.3V +/- 300mV):........................................................................ 25pF

Load Capacitance (VDDVARIO = 2.5V +/- 10%): ............................................................................ 10pF

Load Capacitance (VDDVARIO = 1.8V +/- 10%): ............................................................................ 10pF

Note 6.1 0oC to +70oC for commercial version, -40oC to +85oC for industrial version.

Figure 6.1 Equivalent Test Load

OUTPUT

Test load varies dependent on VDDVARIO:

VDDVARIO = 3.3V ± 300mV: 25pF

VDDVARIO = 2.5V ± 10%: 10pF

VDDVARIO=1.8V ± 10%: 10pF

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6.2.1 Special Restrictions on Back-to-Back Write/Read Cycles

It is important to note that there are specific restrictions on the timing of back-to-back write-read

operations. These restrictions concern reading the control registers after any write cycle to the

LAN9221/LAN9221i device. In many cases there is a required minimum delay between writing to the

LAN9221/LAN9221i, and the subsequent side effect (change in the control register value). For

example, when writing to the TX Data FIFO, it takes up to 135ns for the level indication to change in

the TX_FIFO_INF register.

In order to prevent the host from reading stale data after a write operation, minimum wait periods must

be enforced. These periods are specified in Table 6.1, "Read After Write Timing Rules". The host

processor is required to wait the specified period of time after any write to the LAN9221/LAN9221i

before reading the resource specified in the table. These wait periods are for read operations that

immediately follow any write cycle. Note that the required wait period is dependant upon the register

being read after the write.

Performing "dummy" reads of the BYTE_TEST register is a convenient way to guarantee that the

minimum write-to-read timing restriction is met. Table 6.1 also shows the number of dummy reads that

are required before reading the register indicated. The number of BYTE_TEST reads in this table is

based on the minimum timing for Tcycle (45ns). For microprocessors with slower busses the number

of reads may be reduced as long as the total time is equal to, or greater than the time specified in the

table. Note that dummy reads of the BYTE_TEST register are not required as long as the minimum

time period is met.

Table 6.1 Read After Write Timing Rules

MINIMUM WAIT TIME FOR READ

FOLLOWING ANY WRITE CYCLE

(IN NS)

NUMBER OF BYTE_TEST

READS

(ASSUMING TCYCLE OF 45NS)

ID_REV 0 0

IRQ_CFG 135 3

INT_STS 90 2

INT_EN 45 1

BYTE_TEST 0 0

FIFO_INT 45 1

RX_CFG 45 1

TX_CFG 45 1

HW_CFG 45 1

RX_DP_CTRL 45 1

RX_FIFO_INF 0 0

TX_FIFO_INF 135 3

PMT_CTRL 315 7

GPIO_CFG 45 1

GPT_CFG 45 1

GPT_CNT 135 3

WORD_SWAP 45 1

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6.2.2 Special Restrictions on Back-to-Back Read Cycles

There are also restrictions on specific back-to-back read operations. These restrictions concern

reading specific registers after reading resources that have side effects. In many cases there is a delay

between reading the LAN9221/LAN9221i, and the subsequent indication of the expected change in the

control register values.

In order to prevent the host from reading stale data on back-to-back reads, minimum wait periods have

been established. These periods are specified in Table 6.2, "Read After Read Timing Rules". The host

processor is required to wait the specified period of time between read operations of specific

combinations of resources. The wait period is dependant upon the combination of registers being read.

Performing "dummy" reads of the BYTE_TEST register is a convenient way to guarantee that the

minimum wait time restriction is met. Table 6.2 also shows the number of dummy reads that are

required for back-to-back read operations. The number of BYTE_TEST reads in this table is based on

the minimum timing for Tcycle (45ns). For microprocessors with slower busses the number of reads

may be reduced as long as the total time is equal to, or greater than the time specified in the table.

Dummy reads of the BYTE_TEST register are not required as long as the minimum time period is met.

FREE_RUN 180 4

RX_DROP 0 0

MAC_CSR_CMD 45 1

MAC_CSR_DATA 45 1

AFC_CFG 45 1

E2P_CMD 45 1

E2P_DATA 45 1

Table 6.2 Read After Read Timing Rules

AFTER

READING...

WAIT FOR THIS MANY

NS…

OR PERFORM THIS MANY

READS OF BYTE_TEST…

(ASSUMING Tcycle OF 45NS) BEFORE READING...

RX Data FIFO 135 3 RX_FIFO_INF

RX Status FIFO 135 3 RX_FIFO_INF

TX Status FIFO 135 3 TX_FIFO_INF

RX_DROP 180 4 RX_DROP

Table 6.1 Read After Write Timing Rules (continued)

MINIMUM WAIT TIME FOR READ

FOLLOWING ANY WRITE CYCLE

(IN NS)

NUMBER OF BYTE_TEST

READS

(ASSUMING TCYCLE OF 45NS)

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6.3 PIO Reads

PIO reads can be used to access CSRs or RX Data and RX/TX status FIFOs. In this mode, counters

in the CSRs are latched at the beginning of the read cycle. Read data is valid as indicated in the timing

diagram. PIO reads can be performed using Chip Select (nCS) or Read Enable (nRD). Either or both

of these control signals must go high between cycles for the period specified.

Note: Some registers have restrictions on the timing of back-to-back, write-read and read-read

cycles.

Note: The “Data Bus” width is 16 bits

Note 6.2 When VDDVARIO is 3.3V or 2.5V, the maximum Tdoff time is 7ns. When VDDVARIO is

1.8V, the maximum Tdoff time is 9ns.

Note: A PIO Read cycle begins when both nCS and nRD are asserted. The cycle ends when either

or both nCS and nRD are deasserted. They may be asserted and deasserted in any order.

Figure 6.2 PIO Read Cycle Timing

Table 6.3 PIO Read Timing

SYMBOL DESCRIPTION MIN TYP MAX UNITS

tcycle Read Cycle Time 45 ns

tcsl nCS, nRD Assertion Time 32 ns

tcsh nCS, nRD Deassertion Time 13 ns

tcsdv nCS, nRD Valid to Data Valid 30 ns

tasu Address Setup to nCS, nRD Valid 0 ns

tah Address Hold Time 0 ns

tdon Data Buffer Turn On Time 0 ns

tdoff Data Buffer Turn Off Time Note 6.2 ns

tdoh Data Output Hold Time 0 ns

Data Bus

nCS, nRD

7:1

]

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6.4 PIO Burst Reads

In this mode, performance is improved by allowing up to 16 WORD read cycles back-to-back. PIO

Burst Reads can be performed using Chip Select (nCS) or Read Enable (nRD). Either or both of these

control signals must go high between bursts for the period specified.

Note: The “Data Bus” width is 16 bits

Note 6.3 When VDDVARIO is 3.3V or 2.5V, the maximum Tdoff time is 7ns. When VDDVARIO is

1.8V, the maximum Tdoff time is 9ns.

Note: A PIO Burst Read cycle begins when both nCS and nRD are asserted. The cycle ends when

either or both nCS and nRD are deasserted. They may be asserted and deasserted in any

order.

Figure 6.3 PIO Burst Read Cycle Timing

Table 6.4 PIO Burst Read Timing

SYMBOL DESCRIPTION MIN TYP MAX UNITS

tcsh nCS, nRD Deassertion Time 13 ns

tcsdv nCS, nRD Valid to Data Valid 30 ns

tacyc Address Cycle Time 45

tasu Address Setup to nCS, nRD valid 0 ns

tadv Address Stable to Data Valid 40

tah Address Hold Time 0 ns

tdon Data Buffer Turn On Time 0 ns

tdoff Data Buffer Turn Off Time Note 6.3 ns

tdoh Data Output Hold Time 0 ns

Data Bus

nCS, nRD

7:5

]

4:1

]

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6.5 RX Data FIFO Direct PIO Reads

In this mode the upper address inputs are not decoded, and any read of the LAN9221/LAN9221i will

read the RX Data FIFO. This mode is enabled when FIFO_SEL is driven high during a read access.

This is normally accomplished by connecting the FIFO_SEL signal to high-order address line. This

mode is useful when the host processor must increment its address when accessing the

LAN9221/LAN9221i. Timing is identical to a PIO read, and the FIFO_SEL signal has the same timing

characteristics as the address lines.

Note that address lines A[2:1] are still used, and address bits A[7:3] are ignored.

Note: The “Data Bus” width is 16 bits.

Note 6.4 When VDDVARIO is 3.3V or 2.5V, the maximum Tdoff time is 7ns. When VDDVARIO is

1.8V, the maximum Tdoff time is 9ns.

Note: An RX Data FIFO Direct PIO Read cycle begins when both nCS and nRD are asserted. The

cycle ends when either or both nCS and nRD are de-asserted. They may be asserted and de-

asserted in any order.

Figure 6.4 RX Data FIFO Direct PIO Read Cycle Timing

Table 6.5 RX Data FIFO Direct PIO Read Timing

SYMBOL DESCRIPTION MIN TYP MAX UNITS

tcycle Read Cycle Time 45 ns

tcsl nCS, nRD Assertion Time 32 ns

tcsh nCS, nRD Deassertion Time 13 ns

tcsdv nCS, nRD Valid to Data Valid 30 ns

tasu Address, FIFO_SEL Setup to nCS, nRD Valid 0 ns

tah Address, FIFO_SEL Hold Time 0 ns

tdon Data Buffer Turn On Time 0 ns

tdoff Data Buffer Turn Off Time Note 6.4 ns

tdoh Data Output Hold Time 0 ns

Data Bus

nCS, nRD

FIFO

SEL

[

2:1]

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6.6 RX Data FIFO Direct PIO Burst Reads

In this mode the upper address inputs are not decoded, and any burst read of the LAN9221/LAN9221i

will read the RX Data FIFO. This mode is enabled when FIFO_SEL is driven high during a read

access. This is normally accomplished by connecting the FIFO_SEL signal to a high-order address

line. This mode is useful when the host processor must increment its address when accessing the

LAN9221/LAN9221i. Timing is identical to a PIO Burst Read, and the FIFO_SEL signal has the same

timing characteristics as the address lines.

In this mode, performance is improved by allowing an unlimited number of back-to-back read cycles.

RX Data FIFO Direct PIO Burst Reads can be performed using Chip Select (nCS) or Read Enable

(nRD). When either or both of these control signals go high, they must remain high for the period

specified.

Note that address lines A[2:1] are still used, and address bits A[7:3] are ignored.

Note: The “Data Bus” width is 16 bits.

Note 6.5 When VDDVARIO is 3.3V or 2.5V, the maximum Tdoff time is 7ns. When VDDVARIO is

1.8V, the maximum Tdoff time is 9ns.

Note: An RX Data FIFO Direct PIO Burst Read cycle begins when both nCS and nRD are asserted.

The cycle ends when either or both nCS and nRD are deasserted. They may be asserted and

deasserted in any order.

Figure 6.5 RX Data FIFO Direct PIO Burst Read Cycle Timing

Table 6.6 RX Data FIFO Direct PIO Burst Read Cycle Timing

SYMBOL DESCRIPTION MIN TYP MAX UNITS

tcsh nCS, nRD Deassertion Time 13 ns

tcsdv nCS, nRD Valid to Data Valid 30 ns

tacyc Address Cycle Time 45

tasu Address, FIFO_SEL Setup to nCS, nRD Valid 0 ns

tadv Address Stable to Data Valid 40

tah Address, FIFO_SEL Hold Time 0 ns

tdon Data Buffer Turn On Time 0 ns

tdoff Data Buffer Turn Off Time Note 6.5 ns

tdoh Data Output Hold Time 0 ns

Data Bus

nCS, nRD

FIFO

SEL

[

2:1]

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6.7 PIO Writes

PIO writes are used for all LAN9221/LAN9221i write cycles. PIO writes can be performed using Chip

Select (nCS) or Write Enable (nWR). Either or both of these control signals must go high between

cycles for the period specified.

Note: The “Data Bus” width is 16 bits.

Note: A PIO Write cycle begins when both nCS and nWR are asserted. The cycle ends when either

or both nCS and nWR are deasserted. They may be asserted and deasserted in any order.

Figure 6.6 PIO Write Cycle Timing

Table 6.7 PIO Write Cycle Timing

SYMBOL DESCRIPTION MIN TYP MAX UNITS

tcycle Write Cycle Time 45 ns

tcsl nCS, nWR Assertion Time 32 ns

tcsh nCS, nWR Deassertion Time 13 ns

tasu Address Setup to nCS, nWR Assertion 0 ns

tah Address Hold Time 0 ns

tdsu Data Setup to nCS, nWR Deassertion 7 ns

tdh Data Hold Time 0 ns

Data Bus

nCS, nWR

[

7:1

]

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6.8 TX Data FIFO Direct PIO Writes

In this mode the upper address inputs are not decoded, and any write to the LAN9221/LAN9221i will

write the TX Data FIFO. This mode is enabled when FIFO_SEL is driven high during a write access.

This is normally accomplished by connecting the FIFO_SEL signal to a high-order address line. This

mode is useful when the host processor must increment its address when accessing the

LAN9221/LAN9221i. Timing is identical to a PIO write, and the FIFO_SEL signal has the same timing

characteristics as the address lines.

Note: The “Data Bus” width is 16 bits.

Note: A TX Data FIFO Direct PIO Write cycle begins when both nCS and nWR are asserted. The

cycle ends when either or both nCS and nWR are deasserted. They may be asserted and

deasserted in any order.

Figure 6.7 TX Data FIFO Direct PIO Write Timing

Table 6.8 TX Data FIFO Direct PIO Write Timing

SYMBOL DESCRIPTION MIN TYP MAX UNITS

tcycle Write Cycle Time 45 ns

tcsl nCS, nWR Assertion Time 32 ns

tcsh nCS, nWR Deassertion Time 13 ns

tasu Address, FIFO_SEL Setup to nCS, nWR Assertion 0 ns

tah Address, FIFO_SEL Hold Time 0 ns

tdsu Data Setup to nCS, nWR Deassertion 7 ns

tdh Data Hold Time 0 ns

Data Bus

nCS, nWR

FIFO

SEL

[

2:1

]

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6.9 Power Sequence Timing

Figure 6.8 illustrates the device’s power sequencing requirements. Device power supplies can turn on

in any order provided they all reach operational levels within the specified time period tpon. Device

power supplies can turn off in any order provided they all reach 0 volts within the specified time period

tpoff.

Figure 6.8 Power Sequence Timing

Note: Power must be applied and removed to all 3.3V power supply pins simultaneously (including

the Ethernet magnetics).

Note: Power must be applied and removed to all VDDVARIO power supply pins simultaneously.

Table 6.9 Power Sequence Timing

PARAMETER DESCRIPTION MIN TYP MAX UNITS NOTES

tpon Power supply turn on time 50 ms

tpoff Power supply turn off time 500 ms

VDDVARIO

3.3V (All)

tpon tpoff

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6.10 Reset Timing

Figure 6.9 Reset Timing

Table 6.10 Reset Timing

PARAMETER DESCRIPTION MIN TYP MAX UNITS NOTES

T6.1 Reset Pulse Width 30 ms

T6.2 Configuration input setup to

nRESET rising

200 ns

T6.3 Configuration input hold after

nRESET rising

10 ns

T6.4 Output Drive after nRESET

rising

16 ns

T6.1

T6.2 T6.3

nRESET

Configuration

signals

Output drive

T6.4

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6.11 EEPROM Timing

The following specifies the EEPROM timing requirements for the LAN9221/LAN9221i:

Figure 6.10 EEPROM Timing

Table 6.11 EEPROM Timing Values

SYMBOL DESCRIPTION MIN TYP MAX UNITS

tCKCYC EECLK Cycle time 1110 1130 ns

tCKH EECLK High time 550 570 ns

tCKL EECLK Low time 550 570 ns

tCSHCKH EECS high before rising edge of EECLK 1070 ns

tCKLCSL EECLK falling edge to EECS low 30 ns

tDVCKH EEDIO valid before rising edge of EECLK

(OUTPUT)

550 ns

tCKHDIS EEDIO disable after rising edge EECLK

(OUTPUT)

550 ns

tDSCKH EEDIO setup to rising edge of EECLK (INPUT) 90 ns

tDHCKH EEDIO hold after rising edge of EECLK

(INPUT)

0ns

tCKLDIS EECLK low to data disable (OUTPUT) 580 ns

tCSHDV EEDIO valid after EECS high (VERIFY) 600 ns

tDHCSL EEDIO hold after EECS low (VERIFY) 0 ns

tCSL EECS low 1070 ns

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Chapter 7 Operational Characteristics

7.1 Absolute Maximum Ratings*

Supply Voltage (VDDVARIO, VDD33REG, VDD33A) (Note 7.1) . . . . . . . . . . . . . . . . . . . . . 0V to +3.6V

Positive voltage on signal pins, with respect to ground (Note 7.2) . . . . . . . . . . . . . . . . . . . . . . . . . . +6V

Negative voltage on signal pins, with respect to ground (Note 7.3) . . . . . . . . . . . . . . . . . . . . . . . . -0.5V

Positive voltage on XTAL1/CLKIN, with respect to ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +4.6V

Positive voltage on XTAL2, with respect to ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +2.5V

Ambient Operating Temperature in Still Air (TA). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Note 7.4

Storage Temperature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-65oC to +150oC

Lead Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Refer to JEDEC Spec. J-STD-020

HBM ESD Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..+/- 5kV

Note 7.1 When powering this device from laboratory or system power supplies, it is important that

the absolute maximum ratings not be exceeded or device failure can result. Some power

supplies exhibit voltage spikes on their outputs when AC power is switched on or off. In

addition, voltage transients on the AC power line may appear on the DC output. If this

possibility exists, it is suggested that a clamp circuit be used.

Note 7.2 This rating does not apply to the following pins: XTAL1/CLKIN, XTAL2, EXRES.

Note 7.3 This rating does not apply to the following pins: EXRES.

Note 7.4 0oC to +70oC for commercial version, -40oC to +85oC for industrial version.

*Stresses exceeding those listed in this section could cause permanent damage to the device. This is

a stress rating only. Exposure to absolute maximum rating conditions for extended periods may affect

device reliability. Functional operation of the device at any condition exceeding those indicated in

Section 7.2, "Operating Conditions**", Section 7.6, "DC Electrical Specifications", or any other

applicable section of this specification is not implied.

7.2 Operating Conditions**

Supply Voltage (VDDVARIO) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +1.62V to +3.6V

Supply Voltage (VDD33REG, VDD33A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +3.3V+/-300mV

Ambient Operating Temperature in Still Air (TA). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Note 7.4

Note: Do not drive input signals without power supplied to the device.

**Proper operation of the LAN9221/LAN9221i is guaranteed only within the ranges specified in this

section.

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7.3 Power Consumption (Device Only)

This section provides typical power consumption values for the LAN9221/LAN9221i in various modes

of operation. These measurements were taken under the following conditions:

Temperature: ................................................................................................................................... +25°C

Device VDD (VDDVARIO, VDD33REG, VDD33A):....................................................................... +3.30V

Note: Power dissipation is determined by operating frequency, temperature, and supply voltage, as

well as external source/sink requirements.

Note 7.5 D0 = Normal Operation, D1 = WOL (Wake On LAN mode), D2= Low Power Energy Detect.

Table 7.1 Power Consumption Device Only

MODE Total Power - Typical (mW)

10BASE-T Operation

D0, 10BASE-T /w traffic 249

D0, Idle 243

D1, Idle 146

D2, Energy Detect Power Down 64

D2, General Power Down 11

100BASE-TX Operation

D0, 100BASE-TX /w traffic 380

D0, Idle 370

D1, Idle 272

D2, Energy Detect Power Down (Cable disconnected) 64

D2, General Power Down 11

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7.4 Power Consumption (Device and System Components)

This section provides typical power consumption values for a complete Ethernet interface based on

the LAN9221/LAN9221i, including the power dissipated by the magnetics and other passive

components.

Note: The power measurements list below were taken under the following conditions:

Temperature: ................................................................................................................................... +25°C

Device VDD (VDDVARIO, VDD33REG, VDD33A):....................................................................... +3.30V

Note: Power dissipation is determined by operating frequency, temperature, and supply voltage, as

well as external source/sink requirements.

Table 7.2 Power Consumption Device and System Components

MODE Total Power - Typical (mW)

10BASE-T Operation

D0, 10BASE-T /w traffic 596

D0, Idle 591

D1, Idle 492

D2, Energy Detect Power Down 64

D2, General Power Down 11

100BASE-TX Operation

D0, 100BASE-TX /w traffic 522

D0, Idle 510

D1, Idle 416

D2, Energy Detect Power Down 64

D2, General Power Down 11

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7.5 Worst Case Current Consumption

This section details the worst case current consumption for each device power supply. These values

are provided to assist system designers with proper power supply design. These values cannot be

used to determine typical power consumption of the device. The maximum supply current for each

power supply is provided for the maximum VDDVARIO voltage in all supported ranges as detailed in

Table 7.3, Ta b l e 7 . 4 , and Ta b le 7 . 5.

Note: The current measurements listed below were taken under the following conditions:

Temperature: ................................................................................................................................ Note 7.6

Device VDD (VDDVARIO, VDD33REG, VDD33A): .................................................................... Note 7.7

Note: Current consumption is determined by operating frequency, temperature, and supply voltage,

as well as external source/sink requirements.

Note 7.6 0oC to +70oC for commercial version, -40oC to +85oC for industrial version.

Note 7.7 The device VDD voltage levels are indicated in the supply current tables below.

Note: Above values do not include the supply current for the magnetics. Based on the recommended

implementation, the maximum supply current needed for the magnetics is 108mA.

Table 7.3 Maximum Supply Current Characteristics VDDVARIO=3.3V + 300mV

PARAMETER SUPPLY NAME SUPPLY VOLTAGE MAX CURRENT UNITS

Variable Voltage Supply Current VDDVARIO 3.6V 12 mA

+3.3V Regulator Supply Current VDD33REG 3.6V 85 mA

+3.3V Analog Supply Current VDD33A 3.6V 48 mA

Table 7.4 Maximum Supply Current Characteristics VDDVARIO=2.5V + 10%

PARAMETER SUPPLY NAME SUPPLY VOLTAGE MAX CURRENT UNITS

Variable Voltage Supply Current VDDVARIO 2.75V 9 mA

+3.3V Regulator Supply Current VDD33REG 3.6V 85 mA

+3.3V Analog Supply Current VDD33A 3.6V 48 mA

Table 7.5 Maximum Supply Current Characteristics VDDVARIO=1.8V + 10%

PARAMETER SUPPLY NAME SUPPLY VOLTAGE MAX CURRENT UNITS

Variable Voltage Supply Current VDDVARIO 1.98V 7 mA

+3.3V Regulator Supply Current VDD33REG 3.6V 85 mA

+3.3V Analog Supply Current VDD33A 3.6V 48 mA

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7.6 DC Electrical Specifications

This section details the DC electrical specifications of the LAN9221/LAN9221i I/O buffers. The

electrical specifications in this section are valid over the indicated voltage range and the temperature

range specified in Section 7.2, "Operating Conditions**".

Note: When operating at reduced VDDVARIO voltage levels (less than 3.0V), do not rely on internal

pull-up and pull-down resistors to determine signal state. Refer to the individual signal

descriptions in Chapter 2, Pin Description and Configuration for more information.

Table 7.6 I/O Buffer Characteristics VDDVARIO=3.3V +/- 300mV

PARAMETER SYMBOL MIN TYP MAX UNITS NOTES

VIS Type Input Buffer

Low Input Level VILI -0.3 V

High Input Level VIHI 5.5 V

Negative-Going Threshold VILT 1.01 1.18 1.35 V Schmitt Trigger

Positive-Going Threshold VIHT 1.40 1.61 1.81 V Schmitt Trigger

Schmitt Trigger Hysteresis

(VIHT - VILT)

VHYS 350 423 492 mV

Input Leakage

(VIN = VSS or VDDVARIO)

IIH -10 +10 uA Note 7.8

Input Leakage

(VIN = 5.5V)

IIH 120 uA Note 7.8, Note 7.9

Input Capacitance CIN 2.5 pF

VO12 Type Buffer

Low Output Level VOL 0.4 V IOL = 12mA

High Output Level VOH VDDVARIO - 0.4 VI

OH = -12mA

VOD12 Type Buffer

Low Output Level VOL 0.4 V IOL = 12mA

VOD8 Type Buffer

Low Output Level VOL 0.4 V IOL = 8mA

VO8 Type Buffer

Low Output Level VOL 0.4 V IOL = 8mA

High Output Level VOH VDDVARIO - 0.4 VI

OH = -8mA

ICLK Input Buffer

Low Input Level VILCK -0.3 0.5 V

High Input Level VIHCK 1.4 3.6 V

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Table 7.7 I/O Buffer Characteristics VDDVARIO=2.5V +/- 10%

PARAMETER SYMBOL MIN TYP MAX UNITS NOTES

VIS Type Input Buffer

Low Input Level VILI -0.3 V

High Input Level VIHI 5.5 V

Negative-Going Threshold VILT 0.78 0.94 1.1 V Schmitt Trigger

Positive-Going Threshold VIHT 1.13 1.32 1.51 V Schmitt Trigger

Schmitt Trigger Hysteresis

(VIHT - VILT)

VHYS 304 384 472 mV

Input Leakage

(VIN = VSS or VDDVARIO)

IIH -10 +10 uA Note 7.8

Input Leakage

(VIN = 5.5V)

IIH 120 uA Note 7.8, Note 7.9

Input Capacitance CIN 2.5 pF

VO12 Type Buffer

Low Output Level VOL 0.4 V IOL = 9mA

High Output Level VOH VDDVARIO - 0.4 VI

OH = -9mA

VOD12 Type Buffer

Low Output Level VOL 0.4 V IOL = 9mA

VOD8 Type Buffer

Low Output Level VOL 0.4 V IOL = 6mA

VO8 Type Buffer

Low Output Level VOL 0.4 V IOL = 6mA

High Output Level VOH VDDVARIO - 0.4 VI

OH = -6mA

ICLK Input Buffer

Low Input Level VILCK -0.3 0.5 V

High Input Level VIHCK 1.4 3.6 V

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Note 7.8 This specification applies to all inputs and tri-stated bi-directional pins. Internal pull-down

and pull-up resistors add +/- 50uA per-pin (typical). When operating at reduced VDDVARIO

voltage levels (less than 3.0V), do not rely on internal pull-up and pull-down resistors to

determine signal state. Refer to the individual signal descriptions in Chapter 2, Pin

Description and Configuration for more information.

Note 7.9 This is the total VIN input leakage for the entire device. This value should be divided by

the number of pins driven to VIN MAX to calculate per-pin leakage. For example, if 10 pins

are driven to the maximum operational limit for VIN (5.5V or 5.25V, dependant on

VDDVARIO), the per-pin input leakage is the maximum input leakage current divided by

10.

Table 7.8 I/O Buffer Characteristics VDDVARIO=1.8V +/- 10%

PARAMETER SYMBOL MIN TYP MAX UNITS NOTES

VIS Type Input Buffer

Low Input Level VILI -0.3 V

High Input Level VIHI 5.25 V

Negative-Going Threshold VILT 0.54 0.69 0.83 V Schmitt Trigger

Positive-Going Threshold VIHT 0.878 1.06 1.24 V Schmitt Trigger

Schmitt Trigger Hysteresis

(VIHT - VILT)

VHYS 277 368 525 mV

Input Leakage

(VIN = VSS or VDDVARIO)

IIH -10 +10 uA Note 7.8

Input Leakage

(VIN = 5.25V)

IIH 120 uA Note 7.8, Note 7.9

Input Capacitance CIN 2.5 pF

VO12 Type Buffer

Low Output Level VOL 0.4 V IOL = 4mA

High Output Level VOH VDDVARIO - 0.4 VI

OH = -4mA

VOD12 Type Buffer

Low Output Level VOL 0.4 V IOL = 4mA

VOD8 Type Buffer

Low Output Level VOL 0.4 V IOL = 3mA

VO8 Type Buffer

Low Output Level VOL 0.4 V IOL = 3mA

High Output Level VOH VDDVARIO - 0.4 VI

OH = -3mA

ICLK Input Buffer

Low Input Level VILCK -0.3 0.5 V

High Input Level VIHCK 1.4 3.6 V

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DATASHEET

Note 7.10 Measured at the line side of the transformer, line replaced by 100Ω (+/- 1%) resistor.

Note 7.11 Offset from16 nS pulse width at 50% of pulse peak

Note 7.12 Measured differentially.

Note 7.13 Min/Max voltages guaranteed as measured with 100Ω resistive load.

Table 7.9 100BASE-TX Transceiver Characteristics

PARAMETER SYMBOL MIN TYP MAX UNITS NOTES

Peak Differential Output Voltage

High

VPPH 950 - 1050 mVpk Note 7.10

Peak Differential Output Voltage

Low

VPPL -950 - -1050 mVpk Note 7.10

Signal Amplitude Symmetry VSS 98 - 102 % Note 7.10

Signal Rise & Fall Time TRF 3.0 - 5.0 nS Note 7.10

Rise & Fall Time Symmetry TRFS --0.5nS Note 7.10

Duty Cycle Distortion DCD 35 50 65 % Note 7.11

Overshoot & Undershoot VOS --5%

Jitter 1.4 nS Note 7.12

Table 7.10 10BASE-T Transceiver Characteristics

PARAMETER SYMBOL MIN TYP MAX UNITS NOTES

Transmitter Peak Differential

Output Voltage

VOUT 2.2 2.5 2.8 V Note 7.13

Receiver Differential Squelch

Threshold

VDS 300 420 585 mV

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O

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DATASHEET

7.7 Clock Circuit

The LAN9221/LAN9221i can accept either a 25MHz crystal (preferred) or a 25 MHz single-ended clock

oscillator (±50 PPM) input. The LAN9221/LAN9221i shares the 25MHz clock oscillator input (CLKIN)

with the crystal input XTAL1/CLKIN. If the single-ended clock oscillator method is implemented, XTAL2

should be left unconnected and CLKIN should be driven with a nominal 0-3.3V clock signal. The input

clock duty cycle is 40% minimum, 50% typical and 60% maximum.

It is recommended that a crystal utilizing matching parallel load capacitors be used for the

LAN9221/LAN9221i crystal input/output signals (XTAL1, XTAL2). See Table 7.11, "LAN9221/LAN9221i

Crystal Specifications" for crystal specifications. Refer to application note AN10.7 - “Parallel Crystal

Circuit Input Voltage Control” for additional information.

Note 7.14 The maximum allowable values for Frequency Tolerance and Frequency Stability are

application dependant. Since any particular application must meet the IEEE +/-50 PPM

Total PPM Budget, the combination of these two values must be approximately +/-45 PPM

(allowing for aging).

Note 7.15 Frequency Deviation Over Time is also referred to as Aging.

Note 7.16 The total deviation for the Transmitter Clock Frequency is specified by IEEE 802.3u as

+/- 50 PPM.

Note 7.17 0oC for commercial version, -40oC for industrial version.

Note 7.18 +70oC for commercial version, +85oC for industrial version.

Note 7.19 This number includes the pad, the bond wire and the lead frame. PCB capacitance is not

included in this value. The XTAL1/CLKIN and XTAL2 pin and PCB capacitance values are

required to accurately calculate the value of the two external load capacitors. These two

external load capacitors determine the accuracy of the 25.000 MHz frequency.

Table 7.11 LAN9221/LAN9221i Crystal Specifications

PARAMETER SYMBOL MIN NOM MAX UNITS NOTES

Crystal Cut AT, typ

Crystal Oscillation Mode Fundamental Mode

Crystal Calibration Mode Parallel Resonant Mode

Frequency Ffund - 25.000 - MHz

Frequency Tolerance @ 25oCF

tol - - +/-50 PPM Note 7.14

Frequency Stability Over Temp Ftemp - - +/-50 PPM Note 7.14

Frequency Deviation Over Time Fage - +/-3 to 5 - PPM Note 7.15

Total Allowable PPM Budget - - +/-50 PPM Note 7.16

Shunt Capacitance CO-7 typ-pF

Load Capacitance CL- 20 typ - pF

Drive Level PW300 - - uW

Equivalent Series Resistance R1--50Ohm

Operating Temperature Range Note 7.17 -Note 7.18 oC

LAN9221/LAN9221i

XTAL1/CLKIN Pin Capacitance

-3 typ-pFNote 7.19

LAN9221/LAN9221i XTAL2 Pin

Capacitance

-3 typ-pFNote 7.19

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O

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DATASHEET

Chapter 8 Package Outline

8.1 56-QFN Package

Notes:

1. All dimensions are in millimeters.

2. Position tolerance of each terminal and exposed pad is ± 0.05 mm at maximum material condition.

Dimension “b” applies to plated terminals and is measured between 0.15 and 0.30 mm from the

terminal tip.

3. The pin 1 identifier may vary, but is always located within the zone indicated.

Figure 8.1 56 Pin QFN Package Definition

Table 8.1 56 Pin QFN Package Parameters

MIN NOMINAL MAX REMARKS

A 0.70 ~ 1.00 Overall Package Height

A1 0.00 0.02 0.05 Standoff

A2 ~ ~ 0.90 Mold Cap Thickness

D/E 7.85 8.00 8.15 X/Y Body Size

D1/E1 7.55 ~ 7.95 X/Y Mold Cap Size

D2/E2 5.75 5.90 6.05 X/Y Exposed Pad Size

L 0.30 ~ 0.50 Terminal Length

b 0.18 0.25 0.30 Terminal Width

e 0.50 Basic Terminal Pitch

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O

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SMSC LAN9221/LAN9221i 149 Revision 2.9 (03-01-12)

DATASHEET

Figure 8.2 56 Pin QFN Recommended PCB Land Pattern

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O

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Revision 2.9 (03-01-12) 150 SMSC LAN9221/LAN9221i

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Chapter 9 Datasheet Revision History

Table 9.1 Customer Revision History

REVISION LEVEL & DATE SECTION/FIGURE/ENTRY CORRECTION

Rev. 2.9

(03-01-12)

Section 5.4.8,

"FLOW—Flow Control

Updated Pass Control Frames (bit 2) description to

“When set, the MAC will pass the pause frame to

the host...”

Rev. 2.8

(07-14-11)

Table 2.4, “System and

Power Signals,” on page 18

nLED1 description modified to indicate that the

signal is driven low when operating speed is

100Mbs and is driven high during autonegotiation,

when the cable is disconnected, and during 10

Mbs operation.

Section 5.2.1, "RX FIFO

Ports," on page 78

RX Data FIFO port is aliased to 16 WORD

locations, not 16 DWORD locations.

Section 5.2.2, "TX FIFO

Ports," on page 78

TX Data FIFO port is aliased to 16 WORD

locations, not 16 DWORD locations.

Section 3.6.2.1, "TX

Checksum Calculation," on

page 33

Added note stating TX Checksum calculation

should not be used for UDP packets under IPv6.

Rev. 2.7

(03-15-10)

Chapter 2, "Pin Description

and Configuration," on

page 15

Added pin 1 designator to pin diagram

Section 7.2, "Operating

Conditions**," on page 139

Added note: “Do not drive input signals without

power supplied to the device.”

Section 6.9, "Power

Sequence Timing," on

page 136

Added power sequence timing section

Rev. 2.5

(11-13-08)

All Fixed various typos

Rev. 2.4

(10-24-08)

All Fixed various typos

Table 7.1 on page 140 and

Table 7.2 on page 141

Added power consumption values.

Section 7.5, "Worst Case

Current Consumption," on

page 142

Updated with current consumption values for

various VDDVARIO values.

Section 7.6, "DC Electrical

Specifications," on page 143

Added input capacitance and input leakage values.

Section 3.8, "General

Purpose Timer (GP Timer),"

on page 37

Changed incorrect “GPT_CNT” reference to

“GPT_LOAD”: “On a reset, or when the

TIMER_EN bit changes from set ‘1’ to cleared ‘0,’

the GPT_LOAD field is initialized to FFFFh.”

Section 5.3.23, "E2P_CMD

– EEPROM Command

Corrected MAC Address Loaded (bit 8) type from

“RO” to “R/WC”

Table 7.11 on page 147 Updated crystal specifications:

Drive Level: 300uW

ESR: 50 Ohms.

High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O

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Rev. 2.3

(08-18-08)

Note 7.9 on page 145 Note following I/O Buffer Characteristics table

modified:

Changed from: ".....the per-pin input leakage is 10

divided by the maximum input leakage current."

to: ".....the per-pin input leakage is the maximum

input leakage current divided by 10."

Rev. 2.2

(06-19-08)

Figure 1.2, "Internal Block

Diagram"

Diagram redone.

The word “Core” was added to the regulator block

title.

Table 2.4, “System and

Power Signals,” on page 18

Changed VDD_CORE/VDD18CORE bulk

capacitor value from 10uF to 4.7uF.

Rev. 2.2

(06-10-08)

Auto-negotiation

Advertisement on page 120

Bits 9 and 15 relabeled as Reserved, Read-Only

(RO), with a default of 0.

Auto-negotiation

Advertisement on page 120

Fixed definition of bits 11:10 when equal to “11” by

adding “advertise support for..” to beginning of

definition. Also added note stating “When both

symmetric PAUSE and asymmetric PAUSE

support are advertised, the device will only be

configured to, at most, one of the two settings

upon auto-negotiation completion.”

Section 3.5, "Wake-up

Frame Detection," on

page 26 and Section 5.4.1,

"MAC_CR—MAC Control

Added note: “When wake-up frame detection is

enabled via the WUEN bit of the WUCSR—Wake-

up Control and Status Register, a broadcast wake-

up frame will wake-up the device despite the state

of the Disable Broadcast Frame (BCAST) bit in the

MAC_CR—MAC Control Register.”

Section 5.4.12,

"WUCSR—Wake-up Control

and Status Register," on

page 115

Fixed typo in bit 9: “... Mac Address [1:0] bit set to

0.” was changed to “...Mac Address [0] bit set to 0.”

Section 3.6.1.1, "RX

Checksum Calculation," on

page 32

“checksum = [B0, B1] + C0 + [B2, B3] + C1 + …

+ [0, BN] + CN-1” changed to “checksum = [B1,

B0] + C0 + [B3, B2] + C1 + … + [0, BN] + CN-1”

Section 2.2, “External Pull-

Up/Pull-Down Resistors

Added section. Added references to this section

throughout the pin description tables as applicable.

Rev. 2.1

(05-13-08)

Section 1.1, "Block

Diagram"

Removed the system memory block and arrow

above the microprocessor/ microcontroller

Rev. 1.92

(10-22-07)

Chapter 2 Pin Description

and Configurationon

page 15

Pin assignment information re-organized into

separate table.

EECLK pin description in

Chapter 2 Pin Description

and Configurationon

page 15

Note added to EECLK pin description to indicate

proper usage.

Table 9.1 Customer Revision History (continued)

REVISION LEVEL & DATE SECTION/FIGURE/ENTRY CORRECTION