Intel 82541xx Network Card User Manual


 
Software Developer’s Manual 229
Register Descriptions
The ADVD3WUC bit (Advertise D3Cold Wakeup Capability Enable control) allows the
AUX_PWR pin to determine whether D3Cold support is advertised. If full 1 Gb/s operation in D3
state is desired but the system’s power requirements in this mode would exceed the D3Cold
Wakeup-Enabled specification limit (375 mA at 3.3 V dc), this bit can be used to prevent the
capability from being advertised to the system.
EEPROM settings allow the default PHY behavior to re-negotiate a lower functional link speed in
D3 and D0u states, when PHY operation is still needed for manageability or wakeup capability.
The EN_PHY_PWR_MGMT bit allows this capability to be disabled, in case full 1Gb/s speed is
desired in these states. The PHY is always powered-down in D3 states when unneeded for either
manageability or wakeup support.
Table 13-4. Little-Endian Data Ordering
13.4.2 Device Status Register
STATUS (00008h; R)
This register provides software status indication about the Ethernet controller’s settings and modes
of operation.
Note: TBI Mode is used only by the 82544GC/EI Ethernet controller. Internal SerDes mode is used only
by the
82546GB/EB and 82545GM/EM Ethernet controllers.
BEM = 0 (64-bit mode; Little-Endian)
63 0
08 07 06 05 04 03 02 01
10 0f 0e 0d 0c 0b 0a 09