rob@cires.colorado.edu (Rob Cuthbertson) (07/30/89)
At first, they just wouldn't hang out in the same corner of the room, then
I noticed that they would spread nasty rumors about each other. Since I
can't be expected to run the entire machine room with such petty bickering
going on, I tried to force them to get along, by connecting them together.
Thats where the problem comes in. It seems that hooking a USR Courier 2400
modem to an ADM 12+ terminal is such an impolite thing to do, the terminal will
pop a chip on its rs-232 interface board. (actually, the rs-232 interface
section of its 'motherboard') The chip that goes is a 75154 (?) and the
symptom that this causes is that the terminal will send data fine, but will
not display any incoming data.
Has anyone seen this problem before? Is there something special that I should
do to the cable pinouts before I turn them on? Or is it just that the two
will never co-operate with one another? It isn't the USR 2400's quad switch,
(the one that swaps pins 2 and 3) I've already looked into that. I can't
get any sort of problems from the cable(s) with any other terminal, and I have
tried two different USR 2400 modems, as well as two different ADM 12+'s. Both
modems work fine with any other terminal, and blow that one chip on both ADM's.
I'm at a loss. If you have a clue as to whats going on, PLEASE drop me a line.
I will summarize in E-mail to whomever asks.
--Rob Cuthbertson, CIRES
Co-operative Institute for Research in the Environmental Sciences
rob%cires@boulder.Colorado.EDU
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