Intel 82540EP/EM Network Card User Manual


 
112 Software Developer’s Manual
EEPROM Interface
5.6.19 Circuit Control (Word 21h)
This word is loaded into the Circuit Control Register (CIRC) for setting PCI-X driver strength. See
Table 5-2 and Table 5-3 for suggested values.
Note: PCI-X is not applicable to the 82540EP/EM, 82541xx, and 82547GI/EI.
5.6.20 D0 Power (Word 22h high byte)
If the signature bits are valid and Power Management is not disabled, the value in this field is used
in the PCI Power Management Data Register when the Data_Select field of the Power
Management Control/Status Register (PMCSR) is set to 0 or 4. This indicates the power usage and
heat dissipation of the networking function (including the Ethernet controller and any other devices
managed by the Ethernet controller) in tenths of a watt. For example:
If word22h = 290E, POWER CONSUMPTION (in 1/10W, hex), then:
bits 15:8 = 29h Power in D0a, 29h = 4.1W
bits 7:0 = 0Eh Power in D3h, 0Eh = 1.4W
5.6.21 D3 Power (Word 22h low byte)
If the signature bits are valid and Power Management is not disabled, the value in this field is used
in the PCI Power Management Data Register when the Data_Select field of the Power
Management Control/Status Register (PMCSR) is set to 3 or 7. This indicates the power usage and
heat dissipation of the networking function (including the Ethernet controller and any other devices
managed by the Ethernet controller) in tenths of a watt as described in Section 5.6.20.
5.6.22 Reserved Words (23h - 2Eh)
Words 23h through 2Eh of the EEPROM are reserved areas for the 82541ER.
5.6.23 Reserved Words (23h - 2Fh)
Words 23h through 2Fh of the EEPROM are reserved areas for the 82544GC/EI.