Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!att!mtuxo!mtfmi!mec
From: mec@mtfmi.att.com (M.CONNICK)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Reading the carrier detect line on a modem.
Message-ID: <1275@mtfmi.att.com>
Date: 14 Jul 89 13:27:34 GMT
References: <8338@saturn.ucsc.edu>
Reply-To: mec@mtfmi.UUCP (79153-M.CONNICK)
Organization: AT&T Bell Labs, Middletown NJ
Lines: 16

In article <8338@saturn.ucsc.edu> sirkm@ssyx.ucsc.edu (Greg Anderson) writes:

>A casual inspection of Inside Macintosh didn't get me any information
>about reading the carrier detect line; in fact, it appears that the
>Macintosh serial port doesn't HAVE a carrier detect line.

>Any information on this subject would be appreciated--even if the only
>answer is "it can't be done".

Most Mac modem cables are wired to bring the modem CD signal to the
Mac CTS lead. So you detect carrier loss by checking the status of
CTS.

-----------------------------------------------------
Michael Connick    att!mtfmi!mec        201-957-3057
AT&T Bell Labs     MT 3F-113	        (Dept. 79153)