Path: utzoo!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!decwrl!ucbvax!ucsfcgl!cca.ucsf.edu!wet!rick
From: rick@wet.UUCP (Rick Rutledge)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Re: 360K drive installation problem - FIXED!
Summary: AT/XT differences
Keywords: floppy drive
Message-ID: <1412@wet.UUCP>
Date: 4 Aug 90 01:56:52 GMT
References: <2830.269cca61@cc.curtin.edu.au> <3006.26aedccd@cc.curtin.edu.au>
Reply-To: rick@wet.UUCP (Rick Rutledge)
Organization: Wetware Diversions, San Francisco
Lines: 36

Gumley_LE@cc.curtin.edu.au (Liam Gumley) writes in response to himself:
 >> I just got hold of a spare 5.25" 360K disk drive, so I slotted it into
 >> my old '286, which previously only had a 5.25" 1.2M drive.
 >> However the 360K drive is not working properly. 
 >
 >It is now fixed!  In summary....
 >I found there was an electronic fault with the drive, but once that was fixed,
 >it still did not work.  The steps needed to get it to work were
 >(1) Removing the terminating resistor pack from the 360K drive.  This is
 >apparently a requirement if it is the last floppy drive (B:) in the system.
 >The TRP was located at the back of the disk drive board, and was about the
 >only removable component on the board.

Unless you switched the cable, your A: drive was already the last drive in 
the chain.  I'd be willing to be that if you looked *it* has a terminating
resister...

 >(2) Covering pin 34 on the disk's controller connector with tape.  Someone
 >suggested cutting the corresponding wire on the controller cable, but the tape
 >solution is a bit easier to reverse.  I'm not exactly sure why this works...

This should be the disk change line.  XT's and AT's use a different method
to determine if a disk has been (re)inserted.  Some newer drives have a 
jumper to let you select AT or XT sensing.  We used to cut the trace on the
motherboard, rather than the cable, but the cable would work as well.

 >Thanks to everyone who offered assistance.
 >Cheers, Liam.

You're welcome, though I didn't offer assistance until after the fact.

-- 
------------------------------------------------------------------------------
Rick Rutledge        {hoptoad|ucsfcca|claris}!wet!rick            rick@wet.UUCP
"Voici le secret." dit le renard.  "On ne voit bien qu'avec le coeur.
L'essentiel est invisible aux yeux." -Antoine de St. Exupery, _le Petit Prince_