Path: utzoo!attcan!uunet!ncrlnk!ncr-sd!crash!pnet01!jbritain
From: jbritain@pnet01.cts.com (Jim Britain)
Newsgroups: comp.dcom.modems
Subject: Re: help - Courier HST doesn't connect to us at 1200 bps
Message-ID: <3630@crash.cts.com>
Date: 13 Dec 88 11:57:22 GMT
Sender: news@crash.cts.com
Organization: People-Net [pnet01], El Cajon CA
Lines: 33

The Courier 9600HST, at times can be rather touchy connecting at lower speeds
if set to full "automatic" speed and protocol sensing, when calling other
modems.

The best solution, is to optimize the configuration for each call made,
although that is not always necessary.

The solution that works for connecting to lower speed modems that are fooled
by the request for ARQ correction, is simply to disable it, and also to
disable speeds higher than the system being called.

AT&m0 will disable the negotiation for ARQ correction
AT&n3 will set the top speed of the modem to 2400 baud (n2=1200, but not
necessary).

A complete string to relieve those disconnect errors:
AT&M0&N3

It is also wise, of course, when configuring for individual systems, to 
enter the ATZ string first, so that you know that the modem is truly set to
the default NRAM values.

Or, upon disconnect issue the ATZ string to the modem, so that it is left in a
known state. (I just don't trust these things to stay in a "known" state, if
not in use).

It would also be wise for the user to lock his modem speed to his terminal
speed with the command AT&B1, and keep his speed negotiation totally within
the modem.

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