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Path: utzoo!linus!philabs!prls!pyramid!nsc!curry
From: curry@nsc.UUCP (Ray Curry)
Newsgroups: net.micro.apple
Subject: Re: MODEM INTERFACING
Message-ID: <3583@nsc.UUCP>
Date: Thu, 15-May-86 16:53:40 EDT
Article-I.D.: nsc.3583
Posted: Thu May 15 16:53:40 1986
Date-Received: Sun, 18-May-86 10:51:43 EDT
Reply-To: curry@nsc.UUCP (Ray Curry)
Organization: National Semiconductor, Sunnyvale
Lines: 6

When using a modem with an Apple, one other thing to check is the cable 
orientation.  Apple uses a null modem cable, not a straight rs232 cable.
Transmit and receive are reversed.  If you  have a voltmeter, you can check
the cable pin 2 and pin 3.  The transmitter will have -12 volts and the 
receiver will have +.5 or so.  The modem and the cable should of course
have the opposite results on pin 2 and pin 3.