🚀 go-pugleaf

Is it possible to wire up the console serial port of a Sun server in
such a way that:

    (1) the machine WILL NOT halt if the serial cable is
        unplugged at the terminal end.
    (2) the machine WILL halt in the presence of a software generated
        line break (e.g. via ioctl() calls).
    (3) the machine WILL NOT halt if the connected terminal is
        powered off.

We have been able to achieve (1) and (2) so far with the following
wiring, but not (3).

Sun file                                                     Console
Server                                                       Server
Side                                                         Side


   2  Tx  -------------------------  ------------------------- 2 Tx
                                   \/
                                   /\
   3  Rx  ------+------------------  ------------------------- 3 Rx
                |
                Z    4.7K resistor
                |
  25  -5v ------+                                             25 -5v

   7  GND ---------------------------------------------------- 7 GND

   4  RTS --+                                                  4 RTS
            |
   5  CTS --+                                                  5 CTS

   6  DSR --+                                                  6 DSR
            |
  20  DTR --+                                                 20 DTR

(diagram from "conserver" software by K.S. Braunsdorf & T. Fine)

We need this to work for the 3/160, 4/3X0, SS2, and SS10. If anyone can
suggest to me a method for getting (1), (2), & (3) to work all at once,
I would REALLY appreciate it! Oh, and ya, I know about UPS's, but that's
just not in the cards right now.

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Steve Malowany                                                Systems Analyst
Centre for Pattern Recogn. & Machine Intell.   malowany@cenparmi.concordia.ca
Department of Computer Science                       malowany@cs.concordia.ca
Concordia University                                 Montreal, Quebec, Canada
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