News: 11 March 2016 - Forum Rules
Current Moderators - DarkSol, KingMike, MathOnNapkins, Azkadellia, Danke

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Topics - umaggot

Pages: [1]
1
Programming / ARM/THUMB compared to 6502 ASM?
« on: May 14, 2011, 01:53:08 am »
I have a general question about ARM/THUMB hacking; it's mainly about getting started. Granted I've worked with ASM two years ago -- and fairly recently as well, GBA hacking seems to be a whole new ballpark. I usually use a combination of a cheat finder, debugger, and hex editor, not unlike what FCEUXDSP has. What I want to know is this: how could I apply the same principles -- ruling out addresses with a cheat finder, and then using a debugger to stop all of the action immediately when the address and function I'm looking for has been called, in VBA (or VBALink)?

For a game specific example, The Legend of Zelda: Four Swords for the GBA. I've been using the cheat finder to call out differences between when linked, and when unlinked -- specifically, in-game and after forcing a disconnect (in-game error screen). I haven't been using any specific numbers in the search. The problem is that I can't seem to find any specific address that calls for a link connection. I've tried checking for different address bit sizes as well, but I still end up with 0 entries by the time I'm done comparing. When I had only a handful of addresses that I saved from the search, I'd only managed to successfully find an "A button prompt" cheat (which tells you to press A on the title screen, but doesn't allow you to actually do so and enter the game). My goal is to make the game entirely single-player. If I had to take a guess, I would say that it has something to do with a multiplayer-specific call, that is made on the second VBA Link window. I don't claim to know exactly what I'm talking about, but just out of curiousity, if that were the case -- how would I work around it?

That should just about do it for questions, thank you for taking the time to read this.

Pages: [1]