82801CA Datasheet, PDF (255/521 Pages) Intel Corporation – I/O Controller Hub 3-S (ICH3-S)

LAN Controller Registers (B1:D8:F0)
7.2.12
General Status Register
Offset Address: 1Dh
Default Value: N/A
Attribute:
Size:
RO
8 bits
Bit
Description
7:3 Reserved.
Duplex Mode. This bit indicates the wire duplex mode.
2
0 = Half duplex
1 = Full duplex
Speed. This bit indicates the wire speed:
1
0 = 10 Mbps
1 = 100 Mbps
Link Status Indication. This bit indicates the status of the link:
0
0 = Invalid
1 = Valid
7.2.13 Statistical Counters
The ICH3’s integrated LAN Controller provides information for network management statistics by
providing on-chip statistical counters that count a variety of events associated with both transmit
and receive. The counters are updated by the LAN Controller when it completes the processing of a
frame (that is, when it has completed transmitting a frame on the link or when it has completed
receiving a frame). The Statistical Counters are reported to the software on demand by issuing the
Dump Statistical Counters command or Dump and Reset Statistical Counters command in the SCB
Command Unit Command (CUC) field.
Table 7-6. Statistical Counters
ID
Counter
Description
0 Transmit Good Frames
This counter contains the number of frames that were transmitted
properly on the link. It is updated only after the actual transmission
on the link is completed, not when the frame was read from memory
as is done for the Transmit Command Block status.
4
Transmit Maximum
Collisions (MAXCOL) Errors
This counter contains the number of frames that were not transmitted
because they encountered the configured maximum number of
collisions.
8
Transmit Late Collisions
(LATECOL) Errors
This counter contains the number of frames that were not transmitted
since they encountered a collision later than the configured slot time.
12 Transmit Underrun Errors
A transmit underrun occurs because the processor system bus
cannot keep up with the transmission. This counter contains the
number of frames that were either not transmitted or retransmitted
due to a transmit DMA underrun. If the LAN Controller is configured
to retransmit on underrun, this counter may be updated multiple
times for a single frame.
16
Transmit Lost Carrier Sense
(CRS)
This counter contains the number of frames that were transmitted by
the LAN Controller despite the fact that it detected the de-assertion
of CRS during the transmission.
20 Transmit Deferred
This counter contains the number of frames that were deferred
before transmission due to activity on the link.
24 Transmit Single Collisions
This counter contains the number of transmitted frames that
encountered one collision.
Intel^® 82801CA ICH3-S Datasheet
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