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From: les@chinet.chi.il.us (Leslie Mikesell)
Newsgroups: comp.dcom.modems,comp.misc,comp.unix.sysv386
Subject: Re: Hardware callback devices for frontending/backending a modem.
Keywords: callback device urgent
Message-ID: <1991Apr26.045004.27231@chinet.chi.il.us>
Date: 26 Apr 91 04:50:04 GMT
References: <SFZAX38@xds13.ferranti.com>
Organization: Chinet - Chicago Public Access UNIX
Lines: 21

In article <SFZAX38@xds13.ferranti.com> peter@ficc.ferranti.com (Peter da Silva) writes:

>What information do people have on devices to front-end/back-end a modem
>to implement callback? I envision two classes of devices:

>Call-back on the computer is not an option at this point, due to driver
>bugs in the computer we're using. Replacing the computer would obviate the
>need for this device: we already have software.

I would think that you would want to go back out on a different line
if the call-back is for security reasons.  For that a simple scheme
of logins with shells that effectively do a "ct" to a pre-set number
should work. (But most "ct"s don't negotiate with uugetty very well).
But if the driver bug is the one where setting the speed to B0 to
drop DTR doesn't permit asserting it again, why don't you just
use the smartmodem commands instead to break the inbound connection?
A smarter version of uugetty should be able to do that, as long as
you can turn CLOCAL on and off to give the dialing commands.

Les Mikesell
  les@chinet.chi.il.us