On Sun, 2 Jun 2002, Randy Beaudreault wrote:

> I just read this on the OS X Unix list and thought this would be of 
> interest here with all the 68k floppies having no access and this 
> being a driver for the SWIM3 floppy chip.  Is the SWIM3 on 68k Macs 
> or just IWM?

68k Macs have IWM, SWIM, SWIM II (Q630 and similar), and possibly SWIM III
on the AV Quadras, but I'm not certain on that last one.  The driver would
be of some use for the SWIM and SWIM II, but it would require significant
modifications.

Specifically, everything that this driver does using DMA would have to be
rewritten to make the CPU do the byte-shoving, and the step routines
between tracks would have to be modified to single-step.  It isn't
super-difficult, but it isn't super-easy.  It'd be a good -second- project
for a kernel hacker.  :-)

There are a few other small differences between the various SWIMs (well,
there are a -lot- of differences, but most of them fall into the category
of "features deleted because nobody used them or they didn't work well
enough").

If somebody decides to work on such a port, please email me.


Later,
David

---------------------------------------------------------------------
David A. Gatwood                                dgatwood@gatwood.net
Developer Docs Writer                             dgatwood@apple.com
Apple Computer                                  dgatwood@mklinux.org

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