Intel 82559 用户手册

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Write access to the EEPROM is similar to the read access outlined above, with the differences of a 

write opcode and step 4:

1. Activate the EEPROM by writing a 1 to the EECS bit.

2. Write the read opcode, including the start bit (110b), one bit at a time, starting with the most 

significant bit (1):

a. Write the opcode bit to the EEDI bit.

b. Write a 1 to EESK bit then wait the minimum SK high time.

c. Write a 0 to EESK bit then wait the minimum SK low time.

d. Repeat steps 2.a through 2.c for the next two opcode bits.

3. Write the address field, one bit at a time, starting with the most significant bit.

a. Write the address bit to the EEDI bit.

b. Write a 1 to EESK bit then wait the minimum SK high time.

c. Write a 0 to EESK bit then wait the minimum SK low time.

d. Read the EEDO bit (looking for the dummy 0 bit).

e. Repeat steps 3.a through 3.d until the EEDO bit equals 0, indicating that the address field 

has been completely written.

4. Write a 16-bit word to the EEPROM, one bit at a time, starting with the most significant bit 

(write a data bit to the EEDI bit):

a. Write a 1 to the EESK bit then wait the minimum SK high time.

b. Write a 0 to the EESK bit then wait the minimum SK low time.

c. Repeat steps 4.a through 4.c an additional 15 times.

5. De-activate the EEPROM by writing a 0 to the EECS bit.

The Management Data Interface (MDI) Control register is a 32-bit entity at offset 10h of the CSR. 

The MDI Control register is used to read and write bits from the management data Interface. More 

details regarding the MDI can be found in 

.

SCB Command Word

SCB Status Word

Base + 0h

SCB General Pointer

Base + 4h

PORT

Base + 8h

EEPROM Control Register

Reserved

Base + Ch

MDI Control Register

Base + 10h