Date   : Mon, 05 May 2003 23:10:06 +0000
From   : "W.Scholten" <wouter.scholten@...>
Subject: Re: BBC Micro Games Copy Protection

John Kortink wrote:

> I can remember what a nightmare the tape version of Elite was.
> It used every trick in the book, fake tape blocks, interrupt
> routines, tricky timing, garbled routines, jumping all over
> the place, using almost every free byte in the machine. I did
> manage to hack it (still have the hacked version). I later bought
> the disc version as well though. I had got to see so much of the
> Elite code by then that I built some code to hack out all the
> spaceship wireframe models so you could print them (published
> in A&B Computing June 1986, 'Elite fleet') and increase the
> number of random Saturn dots plotted on the opening screen).

I thought the elite tape version was extremely easy to crack. I remember
the use of an IRQ routine to flip the last block bit for the last file,
but nothing else stands out in my memory as being difficult (I've still
got my cracked version, and the disassembly onto thermal paper... (it's
fading :( )).

First game I tried to crack was fortress. I recall it took some work
(several stages of: read a bit of data that also included new code to
read more from the cassette port, you had to check that code and use all
but the jump to the code from the next decoded block etc.). That also
didn't seem difficult to me, but after that elite seemed really easy.

As other noted, the really tricky ones are supposed to be the Kevin
Edwards games (like galaforce), and Alien 8. I was planning to have a go
last summer to see how difficult it would be but still haven't got round
to it...

Regards,

Wouter

P.S. Was anyone else here disappointed as I was in the tape version of
Elite? No missions, very few ships, no military or mining lasers... (I
only got (a copy of) the disc version in 1995 when I bought a 2nd hand
BBC with disc drive!)
-- 
BBC/atom/old magazine scans etc:
http://www.astro.livjm.ac.uk/~bbc/