Subject: Re: Floppy driver
To: Ron Roskens <garion@mermaid.micro.umn.edu>
From: Mike Schwartz <mykes@shell.portal.com>
List: amiga-dev
Date: 02/27/1994 21:26:02
At  7:08 PM 2/27/94 -0600, Ron Roskens wrote:
>>From the reaches of cyberspace, Brad Pepers wrote:
>>
>> stuff on adosfs deleted.
>>
>> I would also like to look at handling msdos disks. Maybe someone
>> could send me info on msdos disks or after the code is released
>> they can add in msdos disk handling.
>>
>
>If I'm not mistaken there already is support for the msdos file system
>in the form of a gnu msdos file system. Maybe it would be better to
>try to work the code to be able to handle that instead of trying to
>totally rewrite the msdos fs.
>
>Ron Roskens

Handling MS-DOS disks doesn't mean the filesystem.  The IBM PCs have a Western
Digital floppy controller chip that writes sectors to floppy disk differently
than the amiga OS does.  Fortunately, the Amiga hardware is capable of
reading and writing data compatible with the Western Digital controller,
but it's a
radically different program to do so.  In other words, take that amigaOS
compatible floppy driver sources and you can only use the motor on/off and
head stepping code.  The entire rest of the driver needs brand new and
custom code to read the WD controller format.

I actually had code to read/write the WD controller format, as well as code to
read write trackdisk.device format.  I have found the trackdisk format code
and even translated it to C and sent it to mtk.  I'm not much interested in
hacking kernels as other people are - my hopes were that either mtk or
someone mtk found might be willing to work with the code.  I offer to send
anyone the assembly version of the trackdisk format code - it uses the
blitter for mfm encoding and
decoding and has some non-traditional (but superior) features to
traditional trackdisk devices (unix or amigados).  For example, my routines
search the drives for a specific disk instead of requiring that specific
disk to be in a specific drive.  In other words, you can do a dir on the
floppy, eject it and put it in another drive and do dir again and the
software finds the floppy in the new drive...

I'd offer the MS-DOS (actually Atari ST, but same difference) format
routines in assembly, but I haven't been able to find them :(



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