1 Oct
1998
1 Oct
'98
11:55 a.m.
On Thu, 1 Oct 1998, Max Eskin wrote:
Is there a device that would allow _any_ disk,
independently of
format, including Apple ][ disks, to be read? I know Teledisk can do
this for all conventional formats, but not Apple disks. It would be
nice to connect one of these and read the disk image into a file.
The main reason why I ask is for rescuing messed up floppies...
Not quite.
PCs use a disk controller chip based on an NEC 765 design that can not
read ANYTHING other than MFM (some can also do FM), with IBM 3740 style
sector headers. That comprises about 2000 different disk formats that
have been used, but explicitly EXCLUDES GCR of Apple ][ and Mac 400K &
800K; hard sectored; and a few hundred others.
The Western Digital disk controller chips (179X, before they changed over to
NEC style) could do a reasonably real track read of anything MFM
regardless of sector header structure. They were used in TRS-80s and a
LOT of machines OTHER THAN PC.
The Amiga hardware can almost do what you want, or try the old Central
Point Option board.
For diskette recovery, the Option Board is probably about the best
available possibility, but it's discontinud, so you'll need to do some
looking. And it did NOT work reliably on high density, FM, nor many GCRs.
--
Fred Cisin cisin(a)xenosoft.com
XenoSoft http://www.xenosoft.com
2210 Sixth St. (510) 644-9366
Berkeley, CA 94710-2219