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From: curry@nsc.NSC.COM (Ray Curry)
Newsgroups: comp.sys.mac
Subject: Re: Mac+ DTR upside down?
Message-ID: <3897@nsc.NSC.COM>
Date: Tue, 25-Nov-86 17:17:56 EST
Article-I.D.: nsc.3897
Posted: Tue Nov 25 17:17:56 1986
Date-Received: Wed, 26-Nov-86 00:14:33 EST
References: <1372@umd5>
Reply-To: curry@nsc.UUCP (Ray Curry)
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Don't forget that the rs232/rs422 world defines their signals as active (DTR)
but the lines are all physical (DTR-).  DTR- line being held low is active.