Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uunet!motcid!scheer
From: scheer@cell.mot.COM (Jon Scheer)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Floppy drive / controller woes
Summary: 3.5" floppy drive promblems.
Message-ID: <1572@hazel7.UUCP>
Date: 9 Mar 90 02:09:33 GMT
References: <2039@aipna.ed.ac.uk> <90065.133116JIW2@psuvm.psu.edu>
Organization: Motorola Inc., Cellular Infrastructure Div., Arlington Heights, IL
Lines: 34



   The problem is that your floppy thinks it is connected to an XT, and
it is using pin 34 as a Drive Ready indication.  When you hook up a
3.5" floppy to an AT, you want pin 34 to indicate Disk Change.

   Look on the logic board on the floppy.  There will probably be a
jumper labeled  DS/RDY or some such thing.  Usually it is three
pins where you jumper the middle and one of the outside pins.

   This one had me going for months...   (I have a lot of 'war stories'
about hooking up 3.5" drives.)


   Like someone else stated, there is another way you can get around this
problem -- sort of.  You need to hit ^C at the Dos prompt after changing
disks.


   One 3.5" floppy drive that I have doesn't have any jumpers on it.
I get the impression that it was designed for use with an XT.  But
I wonder if I can get it to work on an AT if I put a capacitor
in series with pin 34 so the AT would only see pulses...  Hmmm...
Something to try this weekend...  (Any bets?? :-)

   Hope this helps.

Jon
3/8/90
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