[net.micro.apple] Look Alike Drive Question

notes@harpo.UUCP (11/18/83)

#N::37600002:000:533
!bob    Nov 18 12:13:00 1983




I have recntly purchased CUBIT, a QBERT imitation & find that while it will
boot on a genuine APPLE drive, it will not boot on a Shugart-based lookalike
by TRAK which I just purchased.  It's a full size drive.
The speed is very close, and an alignment test using a disk written on an
APPLE drive shows my look-alike alignment to be virtually identical.
Can anyone give me any help on how to overcome the problem?
						R. L. Carroll
						BTL Whippany
						Rm 2E232A
						Whippany, N.J. 07981
						harpo!bob
						201-386-2609

jhb@ecsvax.UUCP (11/23/83)

If you have a piece of software which will boot on an Apple drive but
not on an Apple look-alike drive, you are unfortunately out of luck.  The
Apple drives are capable of performing various feats which they weren't
designed to do: stepping every quarter track, writing to more than 35 tracks,
and having reproduceable times between tracks.  These features have been
used by many of the copy protection schemes because they are "unreadable"
by standard copy programs.  A protection scheme might include some essential
data in track 36, some data written on track 12.25, and have tracks 15 and
16 synchronized, for example.  Many of the Apple look-alikes aren't
capable of reproducing these tricks: slightly different electronics,
or hardware that was designed slightly differently.  Those drives just
can't run software which uses some of the crazy protection schemes.
-Joe Budge

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