> I've got a Dayna E/CS on my performa 630, so I'm sorta in the same boat.
> According to their tech specs on their web site, it uses a SONIC chip, so
> that driver should mostly work with a bit a massaging. The thing I can't
> find out about so far is the comm slot interface. I looked through Apple's
> Developer Notes and didn't see the comm slot itself mentioned. I basically
> just looked through the headings though as I didn't have time. I plan to
> study it some more later tonight. 

  I have yet to find docs on the CommSlot. Apple does not consider it
an expansion slot, they see it as a way of making different Mac models
(i.e. you're supposed to buy your Mac with something in the
CommSlot, or not at all). Thus there is little or no documentation
for developers.

  One thing you'll need to know is whether there is a ROM or not.
If you can pull the card out of the CommSlot for a moment, check
how many chips there are and their part numbers. There should
be at least one pretty big one with "National Semiconductor"
and "DP8393..." silkscreened on the top. There will likely
be another with the words "PAL" or "GAL" silkscreened
on the top. There may be more.
  If you can jot down the part numbers of all of the chips and
send them to me, I can look them up for you.

  Next you'll need to know the address of the CommSlot,
to know where the Sonic's registers are. It should be somewhere
in the 0x50000000 - 0x60000000 range. You can use the search
function in ddb to look for "2f8", which is the default value
of the Sonic's eobc register. From there we can figure out
what the base address of the Sonic would be.

  After that it should be simple: add a case to if_sn_obio.c 
or if_sn_nubus.c with the correct address and DCR setting,
and you're set.

--Denny