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Path: utzoo!linus!philabs!cmcl2!seismo!umcp-cs!chris
From: chris@umcp-cs.UUCP (Chris Torek)
Newsgroups: net.bugs.uucp
Subject: Re: Modem doesn't hang up after uucico on some sites
Message-ID: <2661@umcp-cs.UUCP>
Date: Tue, 31-Dec-85 07:50:12 EST
Article-I.D.: umcp-cs.2661
Posted: Tue Dec 31 07:50:12 1985
Date-Received: Wed, 1-Jan-86 05:02:30 EST
References: <115@sat-bc.UUCP> <478@uwvax.UUCP> <5821@fortune.UUCP>
Distribution: net
Organization: U of Maryland, Computer Science Dept., College Park, MD
Lines: 35

In article <5821@fortune.UUCP> mats@fortune.UUCP (Mats Wichmann) writes:

> ... modems have the characteristic of only supplying a ready
> signal to the outside world when a connection is established.
> This is good and proper behavior - you don't want to try to
> talk through the modem until there is something on the other
> end. But the poor terminal/system can't even send the "transparent" 
> commands to the modem until it sees this ready signal - like you
> can't send out the commands to establish the connection until
> the conenction is established (don't they call this Catch-22?). 
> So what to you do?

But first, what do others do?

> Well, the modem makers tie the signal permanently high so they
> can guarantee the terminal can always talk to the modem's ROM
> and make it dial.

Ah, but that is the wrong solution:

> Of course, once you have done this, you have broken the modem
> as far as auto-answer, becuase your carrier line never changes
> state (we just finished fixing it to be permanently on, remember).

The *right* solution is to allow the terminal/system to talk to
the modem *before* there is a connection.  Of course you only want
to do this when you are really dialing out.

Dial-out mode to the rescue!  See mod.sources for details.  4.3BSD
version only, sorry; but at least the changes should be obvious to
your local Unix guru, who can then apply them to your system.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 4251)
UUCP:	seismo!umcp-cs!chris
CSNet:	chris@umcp-cs		ARPA:	chris@mimsy.umd.edu