> * WHAT * SPARC 20 printer port?!?
> 
> On the back of an SS20 I see:
> 
>           [MBUS]             [SBUS3]            [SBUS1]
>           [MBUS]             [SBUS2]            [SBUS0]
>                          [dbri]
> [Mono FB] [A/B ser] (KB) [dbri] [TP] [SCSI] [Audio I/O]
> 
> I don't see anything resembling a printer port.  You're probably best off
> shoving your bpp into one of the lower slots on the '20 and going that way.

(The following is all from memory, I don't have a 20 handy to look at,
or even to log into right now and check for SUNW,bpp0 in prtconf, so I
may be about to make a fool of myself. I'm pretty damn sure, though,
which I guess means I'm gonna make even more of a fool of myself by
saying so, if I'm wrong)

The 20 doesn't have ISDN.

Those two ports you've labelled [dbri] are the key. They're not. (the
dbri chip is used for audio, and uses those audio ports at the end)

One is the AUI port (needing Sun's Special Expensive Adapter Cable,
like the one that was used for the ss10 and also put the audio there -
not sure if the 20's port also still supports the audio piggyback for
the external speakerbox), the other is the parallel port (needing
Sun's Special Expensive Adapter Cable exactly like the one that was
used for the 10)

Look closely, you'll see one labelled like "<...>" for ethernet, and
one labelled like "//" for parallel port.  You'll also see that the
little screw-locks on either side of the two ports are keyed, and
slightly different for each port to stop you plugging the wrong
Sun Special Expensive Adapter Cable in the wrong port.

I noted with pleasure recently that the SPARC/Xterminal-1 has a
full-size parallel port, 2 full-size serial ports, and a full-size AUI
(with the stupid clip, but *that* cable nightmare is not Sun's fault).
Not much else, though, which i guess is why.

--
Dan.