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Re: Hardware musings
BLuRry wrote:
I think you're underestimating the complexity a little when it comes to
copy protected disks. Buffering an entire track would work OK for a lot
of titles, but would fail for software that relied on synchronising
tracks.
Yikes! If there are such titles, and they can't be backed up in .nib
format because they're too far off the mark, then how have these things
survived for so long that they can still be backed up and/or hopefully
replicated?
There are *plenty* of titles that do much more complex things than
just checking for track synchronization.
They are preserved by deprotecting them--cracking the protection
scheme and removing it so that the program runs from a "normal" disk.
(Of course, some would say that this fails to preserve the most
interesting part of many programs--their copy-protection scheme. ;-)
It is also possible to make successful "bit copies" of many of them,
provided that someone has reverse-engineered the copy-protection enough
to properly parameterize a bit copy program, like Copy II Plus or
Locksmith.
Copies made in this way retain the copy protection of the original,
so most cannot be imaged for storage or transmission. (The .nib format
is a very simple format which does not work for most advanced copy-
protection schemes.)
Going really far on a limb:
In theory, there's no such things as inifinity or impossibility with
this stuff -- just things that are really darn difficult to fathom
until you can wrap your head around them and break the problem into
small simpler problems. Remember, we're not talking about going
through the disk II controller board, or an IWM chip. So what else
would it take to capture these oddly formatted disks?
Most protected disks are based *precisely* on going through the Disk ][
Controller, and any attempt to dispense with it results in algorithm
failure. Not only are the schemes based on the controller function, but
also on precise timing relationships between events as observed through
the controller.
That's why the problem is so much more easily solved by running a real
Apple II, and why other solutions must essentially recreate an Apple II.
-michael
NadaNet networking for Apple II computers!
Home page: http://members.aol.com/MJMahon/
"The wastebasket is our most important design
tool--and it's seriously underused."