[U-Boot-Users] Smc91c111 - extra bytes in receive buffer

Earle Clubb eclubb at valcom.com
Thu May 20 18:41:53 CEST 2004

I'm trying to get the smc91c111 driver running, but I'm having trouble when
reading received packets from the data register.  There always seem to be
extra bytes between the byte count and the destination address of the
received packet.  For example, here is the beginning of a received arp

407f 0042 ffff ffff ffff 000a 407f 0042
ffff ffff ffff 000a 04d0 cd01 0806 0001
0800 0604 0001 000a 04d0 cd01 c0a8 0b01

As you can see, the status word, byte count, destination address, and the
first two bytes of the source address appear to be duplicated.  Usually the
data separating the first byte count from the second dest address is six
words, but it can vary.  Therefore, I'm not able to just trash the extra
words because I might trash part of the packet as well.

Any ideas on why this might be happening?

Another question: what do the bits in the status word for a receive mean?
I've looked through the data sheet and appnote96 and can't find any
definition of the bits.

Thanks for your help.

Earle Clubb

Software Engineer
Valcom, Inc.

E-mail: eclubb at valcom.com
Voice:  (540) 563-2000 x253
Fax:    (540) 362-9800

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