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

[David Froble]

Steven Schweda wrote:
>> - 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.

The major problem with this description is, from what direction is the 
plug (DB9) (RJ45) being observed ....

:-)

Ask me how I know this ....