At 10:06 Uhr +0200 15.9.2001, Andrew Weiss wrote:
>I am just coming back to 68K OS's and last I heard, the 800K floppy was
>the difficult item to support... at least when doing Mac emulation on a
>PC since the drive is variable speed and almost impossible to
>support. ... I thought FDHD drives did indeed work, however.
>
>I guess I'm mistaken.

Yes. The situation is sort-of inverse on the mac68k side. PeeCee floppy
controllers encapsulate MFM in hardware, whereas the mac68k machines have
to do most of the encoding for GCR and MFM in software. Problem is: GCR was
developed on the Apple II to be easily implemented in software. MFM is much
tougher.

And finally, there is the small problem that the register structure of the
Apple controllers is not documented.

	hauke


--
"It's never straight up and down"     (DEVO)