DM9000A
APPLICATION NOTES
Preliminary 11
Version: DM9000A-AN-V121
November 27, 2007
3.3 Serial EEPROM Operation
The DM9000A supports a serial EEPROM interface. The EEPROM of the DM9000A holds the
following parameters:
1. Ethernet node address.
2. Vendor ID and Product ID auto load.
3. Processor control bus pins polarity setting.
4. Wake-up mode control.
5. PHY ON or PHY OFF while powered up.
6. AUTO-MDIX enable/ disable setting.
7. LED1 & LED2 pins act as IO16 pin and IOWAIT/ WAKE pin in 16-bit mode.
8. LED mode 0 or mode 1 setting.
All of the above mentioned settings are read from the EEPROM upon hardware power-on
reset. The specific target device is IC 93C46, the 1024-bit serial EEPROM. (EEPROM is
93C46/ LC46 such as ATmel, Micro-chip, ATC, and CSI.)
All of accesses to the EEPROM are done in words. All of the EEPROM addresses in the
specification are specified as word addresses.
The default settings of the DM9000A can be changed by the I/O strap pins, or the EEPROM
bits settings with higher priority. The priority for setting the pins polarity is EEPROM > strap
pins > default setting.
3.3.1 EEPROM Format
Name Address
(Word)
Programming
Value (Hex)
Description
Ethernet
Node
Address
0 ~ 2
XX
XX
XX
XX
XX
XX
6-byte Ethernet node address.
Auto Load
Control
3
5445
Bit [1:0] = 00: Disable vendor ID and product ID programming.
*01: Accept vendor ID and product ID programming.
Bit [3:2] = 00: Disable setting of Word 6 Bit [8:0].
*01: Accept setting of Word 6 Bit [8:0].
Bit [5:4]: Reserved = 0.