13 Oct
2008
13 Oct
'08
11:01 a.m.
-------------- Original message from Eric Smith <eric at brouhaha.com>:
--------------
Dave Dunfield wrote:
When I image disked my set, it found both 8 and 10 sector disks. The 3B1 can
format in either 8 or 10 sectors. It looks like the main software is all in 10 sector
disks and the other add on software is in 8 sectors. The 2 disks that failed to image
where from the same add on package, don't remember which and they showed
up as 9 sectors ??? Anadisk finds the same and can read the first 8 sectors and
errors on the 9th.
I might try tonight to reload the OS on another drive to see what the Images them
selves produce.
Jerry
Jerry Wright
g-wright at att.net
most likely there is some other factor in the
8-sector format
which makes it incompatible with the PC disk controller...
I don't remember the particulars of the 3b1 disk formats, but they used
a 2797 FDC, which is certainly capable of reading and writing some disk
formats that the 765 FDCs can't deal with. As you say, there must be
more different than just the 8 sectors per track, as IBM DOS 1.0 used 8
sectors per track on the PC.
Possibly they are using a non-standard code for the sector length in the
address fields.
Eric