Hello Ilya,

Since no one else volutnteered an answer, I'll try my best.

You wrote :

> Folks,
>
> I am running in a bit of a problem here. We received an N4000 machine
> with MPE/iX. On the back panel, there is a port that has " General
> Use/ UPS Serial port" next to it.
>
> Naive as I could be, I was planning to use it as... well, a "General
> Use Serial port" (I have to connect a credit card authorisation PC to
> it).
>
> Now, HP tells me the following : "This port is intended for use with
> UPS only and, although some people have it working with other devices,
> we will not support it". They could not tell why they would not
> support it( No means No I guess).
>
> My question is: are there people around here who have it working ? Are
> there any problems ?
>
> Also, OK, I will try anyway, but what are the alternatives... I don't
> really want to get involved with DTCs unless I have to...
>
> TIA
>
> Ilya

AFAIK, the serial ports that are hooked directly to servers (this goes for
ALL servers, not just the N-Class) do not have flow-control capabilities,
among others. DTC serial ports are under control of DTS, a software piece
actually part of MPE/iX, that handles flow control, buffering, prevents
overflows, etc. These DTS capabilities are not implemented on the
console/modem/ups serial ports directly attached to the server. This is why,
unless you really have a very low activity on the port, no VPLUS, etc., you
should not use these ports.

It's my best guess that it is the reason why HP would not support using
these ports for anything else but their designated usage.

Hope this helps ...

Christian Lheureux

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