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From: TDSTRONG%MTUS5.BITNET@VM1.NoDak.EDU (Tim Strong)
Newsgroups: comp.sys.handhelds
Subject: RE: mac cable to 48sx, using MacKermit
Message-ID: <3876B31980000BC7@gacvx2.gac.edu>
Date: 29 Mar 91 16:12:14 GMT
Lines: 26
Return-path: <@VM1.NoDak.EDU:TDSTRONG@MTUS5.BITNET>
In-reply-to: Your message of Thu, 28 Mar 1991 22:26 CST
To: handhelds@gac.edu

Swap your TX and RX lines.  That I think is the problem.  As I understand
it there are two types of devices when it comes to labeling lines: DTE's
(Data Terminal Equipment) and DCE's (Data Communications Equipment).  When one
attaches a modem or a printer to a computer one is hooking a DCE to a DTE.
In this case the lines are hooked up so that their names match ie TX to TX,
RX to RX.  The problem here is that you are hooking up two DTE's the Mac and
the 48.  In such cases what is needed is called a "null modem" connector.
What this means is that the Send and Recieve lines are swapped inside the cable
so that TX is attached to RX on the other end.

If that all confuses you (sometimes I think us computer people make up
jargon just to feel important), try this.  Look at your diagram.  Notice
how youve labeled TX as output at both ends.  Shouldn't the output of one
machine be attached to the input of the other?  So shouldn't TX be
attached to RX?

Also don't worry about shield.  It can probably be either left unconnected
or hooked to signal ground.

Hope this helps?

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  I__)  _   _I  _   _   TIM STRONG <TDSTRONG%MTUS5.BITNET@CUNYVM.EDU>
  I  \ (_I (_I (_I I    MICHIGAN TECH.    HOUGHTON, MICHIGAN

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