Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!bu.edu!snorkelwacker.mit.edu!mintaka!bloom-beacon!eru!hagbard!sunic!liuida!indic.se!zap
From: zap@indic.se (Jonas Petersson)
Newsgroups: comp.sys.hp
Subject: Re: need HELP with HP MUX board strange behaviour
Keywords: 98642A MUX RS232C 9000/300 irritation
Message-ID: <1991Apr23.201626.13721@indic.se>
Date: 23 Apr 91 20:16:26 GMT
References: <1991Apr19.234717.25668@bronze.ucs.indiana.edu>
Organization: Indic Computerised Air Quality Surveillance
Lines: 42

In article <1991Apr19.234717.25668@bronze.ucs.indiana.edu> teg@peabody.iusb.indiana.edu (Tim Gurbick) writes:
> [a lot about MUX problems]

I have also had a weird problem with the 98642A MUX on 375 and 340 (that is -
all that I've tried with): 

The systems we sell need to have 2 modems, one for data collection at 1200/2400
baud and one for support etc at 19200 baud (a USR HST modem). 

First I try the HST on the internal serial port as I imagined that it would
be the safest. Seemed to work fine but when I try to run something heavy, like
zmodem, it seems to get handshaking problems and starts over all the time.

Now I move the HST to the MUX instead - and strange things start to happen: 
For some reason the RTS wont work unless I try to run kermit on that 
line - kermit fails, but when I quit kermit everything works fine.
If I then run 'cu' on that line it goes back to the initial state again.

But the good thing is that handshaking works fine on the MUX after
running kermit!

So after some hours of trial&error I came up with the solution to
add something like:

mux1::boot:/bin/sh /etc/HSTinit

to /etc/inittab (where HSTinit is a script that runs kermit safely)
and removing the possibility to run 'cu' on that line.

As we need the slow modem anyway there really isn't anything to make a
fuzz about, but I just wanted to point out that there probably are
some minor problems with both serial ports. HP labs people might want
to enlighten us? A glance on the kermit and cu code would help.

		Regards / Jonas

"Just what the world needs - more bugs!" -- Photographer in Arachnophobia.
-- 
     ///  "Are you THE Zaphod Beeblebrox ????" # zap@indic.se
__  ///                                        # Air Quality Surveillance
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 \///  Didn't you hear - I come in sixpacks !" #   in the air..."