Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!samsung!uakari.primate.wisc.edu!crdgw1!ge-dab.ge.com!tarpit!bilver!bill
From: bill@bilver.UUCP (Bill Vermillion)
Newsgroups: comp.dcom.modems
Subject: Re: Passive modem?
Keywords: Modems Passive
Message-ID: <1391@bilver.UUCP>
Date: 22 Nov 90 04:25:29 GMT
References: <457@shum.huji.ac.il-> <1335@bilver.UUCP> <493@shum.huji.ac.il>
Reply-To: bill@bilver.UUCP (Bill Vermillion)
Organization: W. J. Vermillion - Winter Park, FL
Lines: 46

In article <493@shum.huji.ac.il-> marx@vms.huji.ac.il writes:
->In article <1335@bilver.UUCP>, bill@bilver.UUCP (Bill Vermillion) writes...
(all the part about needing/wanting to monitor a line with another
modem deleted - I'm just responding to what I wrote - bill)

->>If you have a "hayes" command set compatible modem set register C to 0 to
->>turn off the transmitter, then set S10 to 255 to ignore carrier status and
->>stay on line all the time, then a D or an A depending on which side of the
->>line you wish to monitor.   You need to monitor the side doing the echoing
->>so you can see what it sent, and what the other side transmitted.
  
  
->Still, Something is missing, you need some string in order to disable
->to handshaking "desire" of this modem, naturally, the modem wants to
->coordinate with the other modems, and this desire must be opressed somehow...

Nothing is missing.   Read your manual.   Set register C to 0 and the
transmit side will be turned off.   It will then be a receive only modem.

Set register 10 to 255.  That will totally ignore carrier, so it will just
sit and listen forever (or until you turn it off).
(Is that what you are talking about the "desire".)

Then by issuing the A or D, you turn the modem receiver to what part of the
line you wish to listen to, the transmit or the receive.
(Or is this what you mean by the "desire".  "desire" is not a standard
modem term ;-}  .

If you are wanting to monitor both sides of a full-duplex connection,
monitor the signal that is coming FROM the unit doing the echoing.

The only thing that won't show are things where echoing is turned off, eg
password entry, and the like.  If you monitor the other side of the line the
only thing you will get is what is transmitted to the host.

If you don't have a Hayes Brand modem, read the descriptions of the
registers described.  If you have a genuine Hayes, look in the manual and
you can even see a diagram.  It's in Appendix G of 1982 manual for the 1200
Smartmodem.   I paid about $550 for that modem discounted.  (Yes Larry,
that's the one I bought from you!).  Things have surely gotten cheaper ;-)



-- 
Bill Vermillion - UUCP: uunet!tarpit!bilver!bill
                      : bill@bilver.UUCP