Re: Disks for 3.5" drive

[dempson@atlantis.actrix.gen.nz (David Empson)]

In article <jeffsterDq8Mqx.EA4@netcom.com>,
The Jeffster! <jeffster@netcom.com> wrote:
> I have an Apple 3.5" disk drive, and when I see that there is an 800k 
> capacity of the disks, I worry, because double-sided, or "low-density" 
> disks are formatted to 720k with an IBM. Are regular low-density disks 
> usable on the drive?

Yes.  Actually, they are "double density" disks (MF2D).  The Apple II
and PC use different low-level formats on these disks.  The Apple II
is able to squeeze more data onto the disk by varying the rotation
speed of the drive, so that it spins faster on the outer tracks and
slower on the inner tracks.

The Mac uses the same physical format on its 400K (single sided) and
800K (double sided) double density 3.5" disks.

Recent Macs are also able to support the 720K PC format and 1.44MB
high density disks (the Mac and PC use the same physical format on
high density disks, but different file systems).

> If not, then can I use a high-density disk and just have the drive
> format it to 800k?

This should work, but is unnecessary.  I wouldn't recommend it unless
you cover up the hole indicating that it is a high density disk, to
avoid confusing a Mac or PC.
-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand