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From: mboen@nixpbe.UUCP (Martin Boening)
Newsgroups: comp.sys.atari.st
Subject: Re: Attaching a CHINON drive to the ST (the saga continues...)
Summary: Disk change pin not used at all!
Keywords: ST, Chinon, diskdrive
Message-ID: <192@nixpbe.UUCP>
Date: 3 Feb 89 09:17:26 GMT
References: <1003@laura.UUCP>
Reply-To: mboening.pad@nixpbe.UUCP (Martin Boening)
Organization: Nixdorf Computer AG, Paderborn, W.-Germany
Lines: 28


Hi folks,

let me add my 2 cents worth to this.

As far as I know (read the Atari ST Profibuch for further info) the disk
change signal of the drive isn't used at all. It isn't even connected (see
specs for the disk drive connector). The Atari recognizes disk changes by
looking at the bootsector of the disk. If the (random generated) serial
number differs from that previously read, a disk change is assumed. That's
why formatters that use a constant to insert as serial number make the
detection of disk changes virtually impossible


A friend of mine had a similar problem. As it turned out he was too
impatient, changing disks while the drive was still selected. The problem
was reconstructable: Waiting for the drive LED to go out before changing
disks made the Atari recognize most disk changes, changing disks with the
drive LED still on made the Atari miss most of the disk changes. This was
on a Mega ST 2 using the internal drive delivered by Atari.

I may be wrong on this, of course. I will look at the Profibuch again to
make sure. I might also try the ATari Floppy Buch. (Both from SYBEX, both
in German)

That's it

Martin