Looking for an 8 bit FDC...

[Fred Cisin]

> >You still have to put up with the "blindness' during the IAM interval and
> >the lack of support for MFM 128-byte sectors--and the lack of support for
> >non-standard address marks (not at all uncommon in old formats).  At least
> >with the WD chips, you can read the raw track data.

On Tue, 25 Oct 2005, Allison wrote:
> Ah huh, what?

The IAM interval is easily handled by masking that signal.  (interrupt the
cable, or (on older cruder drives) cover the index with tape.)

> Who does 128byte MF sectors???  If you really have to it's
> possible to tell a 765 that it's a short sector in mfm.

I have half a dozen formats that I was unable to put into XenoCopy,
due to 128 MFM.  I never could get reliable reading, so I did those with
a 1791.

> As to non standard
> address marks that was a tandyism and 765 "read deleted" works.

I don't remember any non-standard address marks other than Tandy, but
there could have been.
'course the 1791 didn't want to write all of the ones that the 1771 did!


I understand that the 765 multi-sector "track read" was better for MOST of
the market, but WE would rather have had the WD style "raw" track read.

--
Grumpy Ol' Fred     		cisin at xenosoft.com