# $Id: Sun-serial,v 8.1 1998/06/07 16:24:55 ksb Exp $

[ksb sez:
 I don't think you need to do this if your console server box is on a UPS.
 The rest is from Tom Fine.
]

If you are going to be hooking Sun consoles to your console server, you
will run into a problem:  The sun will halt whenever the cable is unplugged.
It will also halt when the the console server is powered off and on.  To
prevent this we modified the wiring of our serial cables at the end that
attaches to the suns.

The server can still be halted by generating a software line break, which
is can be done by sending an escape sequence to the console server.

WE WILL NOT BE HELD RESPONSIBLE FOR ANY DAMAGES CAUSED BY ATTEMPTING A
PARTIAL OR COMPLETE IMPLEMENTATION OF THIS MODIFICATION.
"WE" refers to The Ohio State University and
specifically, the employees of CIS Department of Ohio State.

This is a diagram of the cable we use.

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

I'm not a hardware person, but I think the important part is adding the
resistor.  The rest is icing, more or less.