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Article #7098Re: DTR held high from program control?
From: Ray Curry
Date: Fri, 12 Sep 1986 04:36
Date: Fri, 12 Sep 1986 04:36
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1278 bytes
According to schematics I have for the 512 Mac, the dtr pin on the scc is not connected at all. The pin 6 of the connector is permanently tied to +12 volts. I hear Apple had trouble hooking in their telephone system with built in modems because dtr was permanently held high. Perhaps newer macs have changed this but I have never had my modem hang up even when exiting macterminal and returning. I have been tempted to try opening the mac and connecting the dtr up, but since the scc has to be initialized to use the dtr pin, it would impact any software not doing so, so I haven't. Has anybody every confirmed with a breakout box that the dtr signal ever moves? Perhaps rts/cts are being used and refered to as dtr.
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Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: arc1-ca.pugleaf.net!utzoo!mnetor!seismo!lll-crg!lll-lcc!pyramid!nsc!curry From: curry@nsc.UUCP (Ray Curry) Newsgroups: net.micro.mac Subject: Re: DTR held high from program control? Message-ID: <3773@nsc.UUCP> Date: Fri, 12-Sep-86 00:36:09 EDT Article-I.D.: nsc.3773 Posted: Fri Sep 12 00:36:09 1986 Date-Received: Fri, 12-Sep-86 05:11:42 EDT References: <458@aecom.UUCP> Reply-To: curry@nsc.UUCP (Ray Curry) Distribution: net Organization: National Semiconductor, Sunnyvale Lines: 11