Intel 82540EP/EM Network Card User Manual


 
230 Software Developer’s Manual
Register Descriptions
Table 13-5. Status Register Bit Description
31 13 12 0
Reserved Status
Field Bit(s)
Initial
Value
Description
FD 0 X
Link Full Duplex configuration Indication
When cleared, the Ethernet controller operates in half-duplex;
when set, the Ethernet controller operates in Full duplex.
The FD provides the duplex setting status of the Ethernet
controller as set by either Hardware Auto-Negotiation function,
or by software.
LU 1 X
Link Up Indication
0b = no link config; 1b = link config.
For TBI mode/internal SerDes operation: If Auto-Negotiation is
enabled, this bit is set if a valid link is negotiated. If link is forced
through CTRL.SLU, it reflects the status of this control bit.
For internal PHY mode of operation: Reflects the status of the
internal link signal indicating a transition to a Link Up.
See Section 8.6 for more information about Auto-Negotiation.
Function ID 3:2 0b
Function ID.
Provides software a mechanism to determine the Ethernet
controller function number (LAN identifier) for this MAC. Read
as: [0b,0b] LAN A, [0b,1b] LAN B.
Note: These settings are only applicable to the 82546GB/EB.
For all other Ethernet controllers, set these bits to 0b.
TXOFF 4 X
Transmission Paused
When set, Indicates the transmit function is in Pause state due
to reception of an XOFF pause frame when symmetrical flow
control is enabled. It is cleared upon expiration of the pause
timer, or receipt of an XON frame. Applicable only while working
in full-duplex flow-control mode of operation.
TBIMODE 5 X
TBI Mode/internal SerDes Indication
When set, the Ethernet controller is configured to work in TBI
mode/internal SerDes of operation.
When clear, the Ethernet controller is configured to work in
internal PHY mode.
Note: For the 82544GC/EI, reflects the status of the TBI_MODE
input pin.
For all other Ethernet controllers, set this bit to 0b.