Single-Chip Ethernet Controller with HP Auto-MDIX Support and PCI Interface

Datasheet

4.3.9Missed Frame and Buffer Overflow Counter Reg (MISS_FRAME_CNTR)

Offset:

0020h

Size:

32 bits

The DMAC maintains two counters to track the number of missed frames during a receive operation. The MISS_FRAME_CNTR register reports the current value of these counters and their overflow bits.

BITS

DESCRIPTION

TYPE

DEFAULT

 

 

 

 

31:29

RESERVED

RO

-

 

 

 

 

28

MIL RX FIFO Full Counter Overflow (MIL_OVER)

RC

0b

 

Overflow bit for the MIL_FIFO_FULL counter. This bit is automatically

 

 

 

cleared on a read.

 

 

 

 

 

 

27:17

MIL RX FIFO Full Counter (MIL_FIFO_FULL)

RC

000h

 

This field indicates the number of frames missed due a MIL RX FIFO full

 

 

 

condition. This counter is automatically cleared on a read.

 

 

 

 

 

 

16

RX Buffer Unavailable Counter Overflow (UNAV_OVER)

RC

0b

 

Overflow bit for the RX_BUFF_UNAV counter. This bit is automatically

 

 

 

cleared on a read.

 

 

 

 

 

 

15:0

RX Buffer Unavailable Counter (RX_BUFF_UNAV)

RC

0000h

 

This field indicates the number of frames missed due to receive buffers

 

 

 

being unavailable. This counter is incremented each time the DMAC

 

 

 

discards an incoming frame. This counter is automatically cleared on a

 

 

 

read.

 

 

 

 

 

 

SMSC LAN9420/LAN9420i

115

Revision 1.22 (09-25-08)

 

DATASHEET