[Info-vax] DEC3000->DECServer90TL->CMM comunication problem

[Steven Schweda]

> - we tried to connect a PC with WinXP to the DECServer ports
> through RS232 and "listen" on the Hyperterminal software to
> the ports (setting appropriate transmission parameters) but
> without any success. On the other hand, we are not sure about
> the wiring between the RJ45 -> RS323 (9 pins).

   Sounds reasonable, if you could trust your cable.

   I normally use null-modem cables with 25-pin connectors,
and then 25-pin-to-9-pin adapters when I want to connect to a
9-pin serial port on a computer.  The result seems to be as
follows (which will look better with a fixed-width font):

                  DS90TL port (F)

    i     i     o     -     o     o     o     i      in/out
    1     2     3     4     5     6     7     8
   Rgnd  RXD   Tgnd  CTS   RTS   TXD   DTR   DSR
               Gnd   (nc)   +-----------+

   ---------------------____--------------------


      D-9 (F)
   5  4  3  2  1
    9  8  7  6


         DCE   DS90
         D9F    RJ
   +-- DCD 1 - 8 DSR
   |   TXD 2 - 6 TXD
   |   RXD 3 - 2 RXD
   |   DSR 4 - 7 DTR ----+
   |   GND 5 - 1 Rgnd    |
   |           3 Tgnd    |
   +-- DTR 6 - 8 DSR     |
       CTS 7 - 5 RTS ----+
       RTS 8 - 4 CTS
       RI  9 - nc

   Pins 1 and 6 of the D-9 connector are joined in my
(null-modem) cable.  Pins 5 and 7 of the DS90 are joined by
the DS90.  I don't claim that it's all correct, but it seems
to work here, so it should be adequate for your testing.