Path: utzoo!attcan!uunet!super!udel!gatech!unmvax!intvax!bryan
From: bryan@intvax.UUCP (Jon R Bryan)
Newsgroups: comp.sys.amiga
Subject: Re: Amiga software piracy
Summary: Nah, that doesn't work either.
Message-ID: <649@intvax.UUCP>
Date: 20 Dec 88 20:51:52 GMT
References: <27072@ucbvax.BERKELEY.EDU> <42600045@uicsrd.csrd.uiuc.edu> <5517@cbmvax.UUCP>
Organization: Sandia National Labs, Org. 1411, Albq, NM
Lines: 18

In article <5517@cbmvax.UUCP>, andy@cbmvax.UUCP (Andy Finkel) writes:
> Way back when I did cartridge games, I hit on a method that would
> allow a game to run *only* from cartridge (or write protected ram)...
> 
> All my tests on the static data structures of the game were done using the 
> rotate instructions on the rom.  On the 6502, at least, the status flags and

Way back in '83 (those were the days) when I had a VIC-20, I added an
expansion board to it.  Each of the slots was de-selectable.  I had a
16K RAM cartridge (those really _were_ the days!) that I added
write-protect switches to.  There were also some address switches, I
forget.  I could turn on the machine with a game cartridge plugged in
and disabled, enable the cartridge and copy the contents.  Then I'd load
the game into the RAM cartridge, flip the write-protect switch, shuffle
the addresses (when necessary) and hit the reset button.  As I recall,
Choplifter gave me a bit of trouble because it even had a latch built
into it that used to change its own address (like swapping the two 8K
halves).  But I still got it to work.