[comp.dcom.telecom] Connecting an AT&T ISDN Phone-modem to a DECstation

Ramon F Herrera <ramon@skye.mit.edu> (06/26/90)

AT&T has this nice (relatively) new phone which comes with a DB-25
connector and a built-in modem.  DEC has a (kind of) new, asymmetric,
6-conductor connector used in most of their recent small computers'
and workstations' serial ports.  Both RS232 and RS422 standards are
supported. They call it DEC423.

I recently went through the process of making these devices talk to
each other, specifically for a host computer that receives incoming
calls.  It is very straightforward, except if you want what I call the
'complementary features': the computer should automatically log you
out if the call is lost and conversely, the modem should hang up
whenever the user logs out.

Since there are a couple of tricky steps, such as making a few changes
to both hardware and software, I can E-mail specific instructions to
anyone interested.  Please reply via E-mail.


Ramon F. Herrera
Department of Civil Engineering
Massachusetts Institute of Technology
ramon@iona.mit.edu