
Early Copy Protection on the Apple II - StylifyYourBlog
http://www.fadden.com/techmisc/cassette-protect.htm
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fit2rule
My earliest memory defeating copy protection went like this: typical for games
of my system in those days, programs were loaded from tape, and often
consisted of a small stub program in BASIC to do loading/protection, followed
by raw assembly loaded directly into memory .. if you tried to break out of
the game and return to the BASIC interpreter, the stub loader would trap the
break and issue a "NEW" command, 'wiping' the program from memory.

Well, someone figured out that all the NEW command did was set a single byte
to #400, which was the top of usable memory or something, and then the
interpreter would see .. nothing. So we wrote an "OLD" command that simply
replaced that value with maximum memory avialable - and voila, program loaded
again! I'll never forget the joy of typing in that 10-line OLD command,
loading up a protected game, breaking into BASIC, seeing that the game had
been 'wiped', then typing 'OLD' to get it all back again .. so I could save it
to tape again. That moment sent me off on a wonderful journey that is still
not over, 30 years later .. I think copy protection is responsible for
motivating more software development by hackers over the decades than,
perhaps, any other aspect ..

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patcheudor
Wow, that brought back some memories. I used a darkStar SYSTEMS Snapshot board
on my II+ to copy the contents of a program running in RAM to disk so I could
then use assembler to edit out the copy protection. While my original Snapshot
board is long lost, I still have the IIe version. I believe this would qualify
as a hacking unicorn:

[http://defaultstore.com/copycat.png](http://defaultstore.com/copycat.png)

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kazinator
The later protections were very interesting also.

The Apple II disk drives featured head movement that was operated by
programmed I/O. For increments of a stepper motor were required to go from one
track to another. This made it possible to write data in quarter track
increments, giving rise to one copy protection scheme.

A conventional track-by-track disk copy program would not correctly copy data
written in a spiral pattern using quarter track increments.

There were also schemes whereby tracks were written at a different speed. The
logic-state-sequencer state machine for shifting bits from the head would
still read the data correctly, but the program could tell a copy made at a
conventional speed from the genuine article, due to the different size and
content of the gap.

Programs that did this sort of thing would tend to have to be cracked by
removing all the checks, and replacing their disk loading routines with
conventional ones that read ordinary tracks that are copyable with any disk
copying utility.

~~~
cweiss
The way folks used to duplicate disks protected by custom head-positioning
schemes was through a variety of track-by-track copying programs (Locksmith,
Nibbles Away, and Penulticopy were the most popular IIR) that could be fed
parameter files with custom instructions for head positioning/rotation speed
to duplicate the data for a given piece of software.

These parameter files were generally created by the community, who raced to be
the first to gain fame publishing the keys for whatever just released or
impossible-to-crack software came out. For a brief time, there was a thriving
underground of parameter file traders.

I knew of someone who'd actually compiled a book of parameters, got it printed
at a local copy shop and would sell it for $16 at swap meets. He eventually
got a C&D from the makers of Locksmith claiming that the parameters he was
publishing were covered under their copyright (even though they were created
by the community). Not sure if they actually had a legal case, but he wasn't
about to find out.

~~~
kazinator
The makers of Locksmith took a position which might be called "ironically
consistent", as in: "We make a utility for breaking copyright, so, darn it, it
behooves us to demonstrate deep ignorance of copyright!". :)

I used Nibbles Away and Locksmith, but never for disks that needed the
parameters; just ordinary "garden variety" copying.

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DrTung
Not mentioned was the A2FS1 Flight Simulator Game, I still remember hacking it
to make a tape copy.

1st stage loader was easy, but when I started the game from the tape copy it
just printed:

"Stolen aircraft!" "Stolen aircraft!" etc.

Much later and after some Jolt Colas I got it running on the copy :-)

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CPAhem
aah - a trip down memory lane

