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- Path: tdl.com!tuna
- From: tuna@tdl.com (Chris Cochems)
- Newsgroups: comp.sys.cbm
- Subject: Re: A Hacker's Question..
- Date: 3 Jan 1996 19:33:42 GMT
- Organization: The Diamond Lane
- Message-ID: <4celmm$5a7@news.tdl.com>
- References: <3866938583@news.tdl.com> <820634998@p71.f411.n201.z2.ftn>
- NNTP-Posting-Host: tdl.com
- X-Newsreader: TIN [version 1.2 PL2]
-
- Pontus Berg (Pontus.Berg@p71.anet.canit.se) wrote:
- : In a message of 02 Jan 96 Chris Cochems wrote to All:
-
- : CC> $8000 overrides the programs' RAM pointer! Fastload then makes it's
- : CC> changes, and switches itself back out, leaving you with your
- : CC> reset-protected program in memory!
-
- : You make it sound as if it's all there! "... leaving you with the
- : reset-protected program in memory, or at least the parts of the program that was
- : not trashed by the reset".
-
- : By a reset you can say goodbye to $0000-$07e8, $07f8-$0803, $8000/$a000
- : (whichever is hit with $55 by the resetroutine, depending on how smart you cart
- : is) and also $fd30-$fd50. Not seldom are these areas vital to the game!
-
- Well, Fast Load does a very fast reset, so I think it doesn't trash much
- of anything. It modifies two locations used in BASIC, and switches
- itself out without going through most of the long initialization routines.
-
- Anyway, coders can easily defeat all snapshot carts by putting code to
- read the cartridge IO lines, and making sure all of them return either
- zero or non-constant values. If ANY of those locations contains a
- constant non-zero value, there's a cartridge in for sure. I don't think
- there is a snapshot cartridge that cannot be found in this fashion.
-
- I have seen games (such as Ultimate Wizard) that will not load if you
- have ANY cartridge in. Even with a disabled fastload, it will not work!
-
- It's kinda too bad they put so much work into doing that, cause it's
- really easy to just filecopy the disk, and add your loader code from
- you old cracked copy of WIZARD to crack Ultimate WIZARD. If they had
- just encrypted all the files instead, it would have been a bit tougher to
- crack.
-
- As it is, my cracked copy of Ultimate Wizard is compatible with Fast
- Load, where the original is NOT!
-