Date:	Wed, 14 Apr 1999 17:59:13 +0100
From:	Matthias Paul <PAUL-MA AT reze-1 DOT rz DOT rwth-aachen DOT de>
Subject:	Re: Maximum floppy drive size
To:	opendos AT delorie DOT com
Message-id:	<2B945DA2589@reze-1.rz.rwth-aachen.de>
Organization:	Rechenzentrum RWTH Aachen
X-Mailer:	Pegasus Mail v3.22
Reply-To:	opendos AT delorie DOT com

A long while ago, on Tue, 23 Feb 1999, Ray Greene wrote:

> I have come across a driver called ZapA that will let you access and boot
> from a Zip drive as though it were a floppy drive - the Zip drive becomes
> a: or b: - at http://www.blueskyinnovations.com
> 
> However, it says that MS-DOS will only recognise up to a 32Mb floppy drive,
> which is a waste of a lot of Zip disk space.
> 
> Can anyone tell me if OpenDOS has the same 32Mb limit for floppy drives? 

As others have already answered, DOS assumes floppies to be FAT12, 
which explains the 32 Mb limit. However, there is also another 
limitation, the maximum count of sectors per track. DR DOS tools like
FORMAT, DISKCOPY, and DISKCOMP will (currently) support a maximum of 
36 sectors per track for removable floppy-like media, since this is 
the sector count of 3.5" extra-density (ED) floppies (2.88Mb/4Mb), 
which, however, failed to get a larger acceptance. This is due to 
code allocating memory for track buffering.

Matthias 

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eMail: <Matthias DOT Paul AT post DOT rwth-aachen DOT de>
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