Path: utzoo!attcan!uunet!mcvax!piet
From: piet@cwi.nl (Piet Beertema)
Newsgroups: comp.dcom.modems
Subject: Re: autobauding a TrailBlazer on a UNIX PC
Message-ID: <514@sering.cwi.nl>
Date: 25 May 88 09:43:42 GMT
References: <282@ditka.UUCP> <1030@astroatc.UUCP> <240@bungia.Bungia.MN.ORG>
Organization: CWI, Amsterdam
Lines: 27


	>Oh!  One other thing - Be sure to set S55 to 3 on dial-in modems.  It
	>enables the machine that is dialing in to send a +++ and not take your
	>modem off-line.
Arrgh! That explains a problem I've been having for some time
and that Telebit couldn't explain either (telebit!modems, are
you listening?): after a +++ escape sequence, I couldn't get
the thing online again with ATO; only the sequence
  AT%O
  ATO
would restore the connection, but for that to work I had to
enable remote access on the dialin modem; not really acceptable.

The explanation is that I had set S55=0 (the default value) on
the dialin modem. I would have expected the modem to look for
the +++ escape sequence *only* in data coming in via the RS232
port. But apparently it also recognizes +++ as such when it
comes in via the line: that means the modems on *both* ends
were taken offline by one escape sequence, and thus both of
them needed an ATO command to go online again. This looks
pretty much like a bug to me.

Thanks for the hint!

-- 
	Piet Beertema, CWI, Amsterdam
	(piet@cwi.nl)