307013-003 Datasheet, PDF (328/848 Pages) Intel Corporation – Intel I/O Controller Hub 7

LAN Controller Registers (B1:D8:F0) (Desktop and Mobile Only)
Table 8-6.
Statistical Counters (Sheet 2 of 2)
ID
Counter
Description
This counter contains the number of frames that are both
misaligned (for example, CRS de-asserts on a non-octal
44
Receive Alignment
Errors
boundary) and contain a CRC error. The counter is updated, if
needed, regardless of the Receive Unit state. The Receive
Alignment Errors counter is mutually exclusive of the Receive
CRC Errors and Receive Short Frame Errors counters.
48
Receive Resource
Errors
This counter contains the number of good frames discarded due
to unavailability of resources. Frames intended for a host whose
Receive Unit is in the No Resources state fall into this category. If
the LAN controller is configured to Save Bad Frames and the
status of the received frame indicates that it is a bad frame, the
Receive Resource Errors counter is not updated.
52
Receive Overrun
Errors
This counter contains the number of frames known to be lost
because the local system bus was not available. If the traffic
problem persists for more than one frame, the frames that follow
the first are also lost; however, because there is no lost frame
indicator, they are not counted.
56
Receive Collision
Detect (CDT)
This counter contains the number of frames that encountered
collisions during frame reception.
60
Receive Short
Frame Errors
This counter contains the number of received frames that are
shorter than the minimum frame length. The Receive Short
Frame Errors counter is mutually exclusive to the Receive
Alignment Errors and Receive CRC Errors counters. A short frame
will always increment only the Receive Short Frame Errors
counter.
64
Flow Control
Transmit Pause
This counter contains the number of Flow Control frames
transmitted by the LAN controller. This count includes both the
Xoff frames transmitted and Xon (PAUSE(0)) frames transmitted.
68
Flow Control
Receive Pause
This counter contains the number of Flow Control frames
received by the LAN controller. This count includes both the Xoff
frames received and Xon (PAUSE(0)) frames received.
Flow Control
72 Receive
Unsupported
This counter contains the number of MAC Control frames
received by the LAN controller that are not Flow Control Pause
frames. These frames are valid MAC control frames that have the
predefined MAC control Type value and a valid address but has
an unsupported opcode.
76
Receive TCO Frames
This counter contains the number of TCO packets received by the
LAN controller.
78
Transmit TCO
Frames
This counter contains the number of TCO packets transmitted.
The Statistical Counters are initially set to 0 by the ICH7’s integrated LAN controller
after reset. They cannot be preset to anything other than 0. The LAN controller
increments the counters by internally reading them, incrementing them and writing
them back. This process is invisible to the processor and PCI bus. In addition, the
counters adhere to the following rules:
• The counters are wrap-around counters. After reaching FFFFFFFFh the counters
wrap around to 0.
• The LAN controller updates the required counters for each frame. It is possible for
more than one counter to be updated as multiple errors can occur in a single frame.
• The counters are 32 bits wide and their behavior is fully compatible with the IEEE
802.1 standard. The LAN controller supports all mandatory and recommend
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Intel ^® ICH7 Family Datasheet