On Mon, 8 Mar 1999, Paul Mather wrote:
SNIP..............
> -----
> Console on a DEC VAXstation 3100 or DECstation 3100:
> Connector: mmj
> 
>                           Corresponding 25 pin RS-232 pins
> 1 DTR                                  20
> 2 TD (+)                                2
> 3 TD (-)                                7
> 4 RD (-)                                7
> 5 RD (+)                                3
> 6 DSR                                   6
> 
> This isn't RS-232, its a differential interface (hence the + and - pins) 
> (RS-422?).
> -----

	Can't be RS-422 because it swings too far and isn't truly
differential. If it were differential, there wouyld be no ground reference
for the handshaking lines. I believe that it is actually RS-423 (same as
newer VTxxx terminals) which is inter-operable with RS-232...

PCW