I've run into this similar problem.  I believe the problem is caused by the
network card being used in a jumperless configuration.  Many NE2000 network
controllers have additional non-NE2000 defined features that allow base i/o
addresses and other configuration info to be stored in the controller itself.

For instance, the Realtek 8019AS chip has a whole series of configuration
registers in Bank3 of the non-volatile register file.  If the controller is set
to this mode, you must determine (trial and error...) the base i/o address and
then modify the config info.  One chipset that I looked at had some very high
base address that you could write to 3 times to change the configured base
address.  I don't remember what chip that was, I want to say it was an SMC chip,
but I'm not sure.

You may be able to reset the base address with a utility created by the card's
manufacturer or an OS.  I tried putting mine in a windows machine and it didn't
actually save new  config data.  I don't like to shutdown my linux box, so I
didn't try it in there :)

Anyways...  I think to figure it out, your going to need to see the datasheet
for whatever chip that card has.  I'm not sure how you would find that out
exactly.  You could try using it in a linux machine and see what modules it
uses.  Typically ne2k cards use the 8390 module for the core ne2k support and
then some other module to get at the special features of the given card.

Hope that helps,
Eric


On Tue, 9 Mar 2004 16:25:23 -0500
Herbert Graf <mailinglist2@FARCITE.NET> wrote:

> > >         I suppose it's possible they've been rebadged, I don't
> > > know. One is on a
> > > DE-220 NIC and the other is on a DE-250 NIC. I haven't been able
> > > to find any
> > > info on them. Thanks, TTYL
> >
> > I don't know the chip, but if you want to interface your PIC to
> > the ethernet
> > using the cards (I am guessing here), you could connect directly
> > to the ISA
> > connection on the card.  There is info on the ISA bus at
> > http://www.techfest.com/hardware/bus/isa.htm.  Otherwise, I guess
> > you could
> > trace the tracks back to the IC to find out which signals are on
> > which pin.
> > If you need to repair one, then it probably wouldn't help.
>
>         I am interfacing to ISA NICs using the code from the picnic project.
>
>         The problem is the DE-250 card is working but my DE-220 cards act like
>         they
> aren't there, every register read comes back 0xff. I've confirmed the
> address being addressed and all looked fine until I noticed that bits 11, 12
> and 13 were being pulled up high by the card all the time??
>
>         I need the datasheet of the chip to figure out why it's in this state,
> perhaps it's not 100% NE2000 compatible, or perhaps there's a part of the
> NE2000 initialization was being skipped. My theory so far has been perhaps
> ISA PnP getting in the way: i.e. the cards are waiting to start the PnP
> process, but further research seems to point to no on that theory.
>
>         The DE-250 card is working, but poorly, again I'm working under the
> assumption that there is some slight deviation in either the PIC's routines
> or NE2000 compatibility of the cards.
>
>         TTYL
>
> ----------------------------------
> Herbert's PIC Stuff:
> http://repatch.dyndns.org:8383/pic_stuff/
>
> --
> http://www.piclist.com hint: The PICList is archived three different
> ways.  See http://www.piclist.com/#archives for details.

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