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From: chad@norge.dec.com
Newsgroups: comp.sys.atari.st
Subject: Re: Fujitsu Drive Problem
Message-ID: <1272@hiatus.dec.com>
Date: 23 Jun 89 13:52:05 GMT
References: <-286589998@hpcupt1.HP.COM> <741@lilink.UUCP>
Sender: news@hiatus.dec.com
Organization: Digital Equipment Corporation, Nasua, NH USA
Lines: 13


I too added a toshiba DSDD drive to my 520 STFM.  I too had the problem of
non-protected disks not signalling media change.  Someone in my company sent me some
USENET articles from long ago discussing this.  I added a 1n1418 diode from
pin 34 (most drives use 2 -- head load here, mine had pin 34 as media change detect so
I used that instead) to pin 28, write protect detect.  It should modulate the signal
from 2/34 onto pin 28, write protect detect.  This should fix the media change 
problem.  However, this leads to another problem in some drives.  Non-protected disks
sometimes appear write protected.  Wht I ended up doing (just a couple days ago
in fact) was to buy a $0.40 slide switch at Radio Shack and to switch the
diode.  I normally leave it closed for media detection but now when I have non-protected disks showing up protected I just flip the switch and all is as normal.

Chad