20000 Leagues Under the Sea

I upped this game to the ADF Zone a few days ago (wrongly calling it 20000 MILES Under the Sea, mea culpa )... it has a manual copy protection (based on a colour chart that was included with the original game) that will produce a "Software Failure" error message when I click on the wrong colour. Can someone please have a look at this game?

Let's get this thread back on top.

Still looking for a crack of 20000 Leagues Under the Sea, i.e. the English version of this game! Mind you, not the "unofficial" translation (done by Ackerlight) of the French version (with the French title screen), but a crack of the official English version!

[Ian]

You see Codetapper has challenged AmigaBoy to crack it, lets see if Amigaboy is up to it

What ya' say Amigaboy are you going to do it??

hehe. Lemme check out Fighter Duel Pro first.....I'm also working on Neuromancer and Indianopolis 500 (only getting rid of manual protections....not disk protections)

I might check out 20000 leagues later

Great news. I'd really like to see this game cracked. GO Amigaboy, GO!!!

Can someone upload it?

I don't think I have it

[Codetapper]

AmigaBoy: 20000 Leagues under the Sea is now in the ADF zone.

These Dos games aren't quite so easy to crack, but from a brief look at the code it doesn't appear to be encrypted (the check part anyway). No doubt the list of colours and combinations are at least eor'd to give a bit of protection.

If you get stuck and need any help, gimme a yell and I'll take a proper look but you try and crack it first. We need more crackers around here

heh. Thanks dude

I prefer "reverser" over "cracker", but hey, call it what you want

bleh

I just looked at this game (for about 1 hour!) and I got absolutely nowhere

I set breakpoints all over the place, and nothing. Kwap

The reason I'm having trouble is, it's a DOS game. I don't want to resort to having to learn the Amiga's OS until I master NDOS and the like.

Anyway. Let me tell ya what I tried, and you can tell me what I'm doing wrong

First. I tried to break on any access of the "Consult the color chart" message. This would allow me to see where it starts the protection.....but it didn't break

And then....I decided to try to break on any access of the number we're supposed to look up in the manual, but this number kept jumping around in memory

And then....I decided to try to break on any access to the actual colours (even though they're probably part of the Consult the color" thingy)....but it didn't break

And then....I decided to search for any instructions that would maybe load the addresses of ANY of these.....And I found none

And then.....No and then!

Actually, after that I decided to start mucking around with PAL/NTSC switching, but my experiments went horribly wrong (this has nothing to do with the game btw)

C00000 move.b #0,$dff1dc ; Switch to NTSC....Works fine
C00008 jmp $c00000

While in NTSC

C00000 move.b #32,$dff1dc ; Supposed to switch to PAL...Didn't work
C00008 jmp $c00000 ; Is it cause I'm on KS1.3?

[Codetapper]

First, the PAL/NTSC thing requires ECS/AGA chipset. On an OCS machine, it will do nothing as that register doesn't exist.

I suspect when you are doing the move to $dff1dc it is changing but you are probably in the AR cart at that time and switching it straight back to what it previously was. If you ran it as a program on ECS/AGA I am sure it would work. (That's all the AGA fix intro I use does).

[BTW if you are trying that PAL/NTSC stuff for Fighter Duel Pro, don't! That has nothing to do with the PAL/NTSC check, I'll bet it checks the frequency via Execbase looking for #50 or #60 to decide whether it's PAL or NTSC. When you move.b #$20,$dff1dc it doesn't change ExecBase at all so the game will still say "sorry, needs a PAL machine" or whatever. You must kill the check routine not just hardwire $dff1dc].

As for 20000 leagues, yeah Dos games suck. You could try searching for $bfe001 accesses for when you press the mouse down on a colour?

(The other thing which would be good but is a slim chance would be when the game crashes, it might do the RESET command so if you searched for that opcode you could trace backwards from there. It could crash via other means however so there is probably not much of a chance that you will succeed via this method. ie. game could just set a0=0 and clear (a0)+, increment it and keep clearing until the amiga crashes!)