Date   : Tue, 15 Oct 1985 08:40:12 EDT
From   : "Kenneth E. Van_Camp" (LCWSL) <kvancamp@PICA-LCA.ARPA>
Subject: Reading & writing 48 tpi on 96 tpi drives

Please note that I DID say I'm using DOS 2.10 to write my 48 tpi disks on
the 96 tpi drives. I can't say what happens after the disks have been on
the shelf for a year because I've only had my AT a few months. I have
definitely been able to read these 48 tpi disks on my XT, though, so I am
NOT just reading them on the same kind of drive I'm writing on. (The XT has
standard 48 tpi drives.) As far as brands are concerned, my 96 tpi drive
is the standard one that comes with all AT's from IBM. I would estimate
that I've read at least 15 diskettes on a 48 tpi drive that were created on
the 96 tpi drive. That may not be enough to reach any definite conclusions,
but so far success has been 100%. I should also mention that about half of
these diskettes were 48 tpi, the other half 96 tpi formatted to 48. So the
statement that you shouldn't use the 96 tpi disks at 48 format doesn't seem
to hold, either.
       I can't remember if there's any difference between the way DOS 2.10
and DOS 3.0 write 48 tpi diskettes, because I've always used strictly DOS
2.10. Can someone help me out on that? If there is, then this may be the
source of the problem for you 3.0 people. Using the HIDE/UNHIDE utilities
in the public domain you should be able to rename you hidden dos files and
maintain both operating systems on your hard disk. Or come to think of it,
I guess all you'd need is both versions of FORMAT.
               --Ken Van Camp