Path: utzoo!attcan!uunet!cs.utexas.edu!tut.cis.ohio-state.edu!pt.cs.cmu.edu!rochester!rit!ultb!clf3678
From: clf3678@ultb.isc.rit.edu (C.L. Freemesser)
Newsgroups: comp.sys.atari.st
Subject: Re: Experience with Toshiba 3 1/2 inch double sided drives?
Summary: Media changes
Message-ID: <1662@ultb.isc.rit.edu>
Date: 24 Nov 89 03:21:06 GMT
References: <3156@csv.viccol.edu.au> <1705@hiatus.dec.com>
Reply-To: clf3678@ultb.isc.rit.edu (C.L. Freemesser)
Organization: Information Systems and Computing @ RIT, Rochester, New York
Lines: 21

To fix the media change problem with homebrew 3.5 inch disk drives, run
a jumper between pins 2 and 28 on the drive's 34 pin connector.  I've
found that using 30 AWG wire works well.  Take a small bit of wire, and
solder the ends to the back of the drive's connector.  The even numbered
pins stick out the back of the connector.

On some drives, this will cause the disk to be "permanently" write
protected.  My Tandy/Teac drive has this problem.  My guess is that the
signals aren't getting through to the computer.  You might try using a
diode instead of a wire, but that hasn't done much good either.

I'm not an electronics expert (yet), but this fix seems to work fine.
Of course, TOS 1.4 fixes this problem, so you don't have to run a
jumper.


Chris Freemesser, Rochester Institute of Technology :BITNET:%clf3678@RITVAX
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