Emax

> FYI...Shugart, is the last name of the guy who
> invented the Floppy Drive, and subsequently the Hard
> Drive. All Floppy drives are technically "Shugart"
> drives.

Hmm, kinda...  "Real" Shugart drives, as used in old Ensoniq kit (I'm
guessing Emu too)
have slight differences in the pins from "AT" floppy drives, as used in
PC's.  Generally 720k (DD)
PC drives have the Shugart nature.
The differences are slight.  The step/direction/write/read etc.  pins are
just the same.
It's more to do with the motor enable/drive select pins.  Disk change/disk
ready are also slightly different.
However, most older machines can be tricked into ignoring this, or at worst
behaving in a slightly odd way when asked to read a drive with no disk in
(decides drive is ready, falls over reading disk).
If you're lucky, the Shugart bus you're connecting to might expect a drive
on DS1.  DS1/Motor on corresponds to DSB/Motor B on a PC/AT drive.

> Apple drives work a little differently, I'm
> not sure if they are diferent enough to be considered
> non-Shugart or not.

They're very very different.  Not just the motor eject, they run at variable
speeds.  They're not true constant linear velocity, but they do speed up and
slow down when reading 720k disks.  They don't do it for 1.44M disks though.
Furthermore, Mac disk interfaces use a special custom magic Apple chip (IWM)
which uses a different disk format - GCR instead of MFM.  Finally, the plug
is different, just to put the tin hat on things.

> In anycase, sounds like newer drives might need
> modification to work in an Emax. As I mentioned in a
> previous message, new floppy drives can be modified to
> work in an Atari ST, so I suppose it's possible to
> modify one for an Emax.

HTH,
  Gordon.