On Tue, 24 Sep 96 16:01:16 -0600 
 Greg Oster <oster@cs.usask.ca> wrote:

 > Are there any known problems with NetBSD 1.2 auto-sensing the 10base2
 > Ethernet connection on a DEC Multia [21066, 166MHz, 24MB RAM]?  

I had the same problem w/ my Multia.  The problem is that the 21040
can't software select between the bnc/aui.  Basically, I think the
world looks like this:


              -------- UTP
              |
        Tulip |                    -------- AUI
              |                    |
	      -------- Transceiver |
				   |
				   -------- BNC

So, the Tulip choses "UTP" or "Transceiver" ... then, you have to tell
the transceiver which port to use.  On the 21040 PCI cards, this is a
jumper.  Matt Thomas told me once that, on the Multia, it's some
Multia-specific register that the de driver doesn't know about.

 > On NetBSD bootup it prints:
 >   ...
 >   de0: enabling Thinwire/AUI port
 >   ...

...which is why you see this, since it's really selecting the
thing that gives you "Thinwire/AUI" ... but it doesn't know which
of the two it's giving you :-)

 > I'd like to hear from anyone who's got a Multia and is using the 10base2 
 > Ethernet connection in NetBSD.  All indications from the net are that it 
 > should work just fine.  I'd just like to confirm that my case is "abnormal", 
 > and that I'm missing something else.... 

I haven't gotten the BNC working on my multia ... I just have a transceiver
plugged into the AUI for now (there wasn't much room, so I had to ... 
modify the transeiver a bit.. :-)

To do it right, we probably need a better way of selecting media in
general (if_media longword in struct ifnet, with some encoding of
media based on interface type; there was a really sane proposal on
bsdi-users some months ago... Matt?  Do you still have that?).
Once media selection is solved, maybe a machine-dependent callback
to deal with the appropriate frobbing ...

 -- save the ancient forests - http://www.bayarea.net/~thorpej/forest/ -- 
Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                               Home: 408.866.1912
NAS: M/S 258-6                                          Work: 415.604.0935
Moffett Field, CA 94035                                Pager: 415.428.6939