Lost on PS2 Hacking

[bungholio]

I was going to attempt hacking on the PS2 and have read a bunch of stuff, but I don't know what's what.

I read a tutorial on getting master codes and I think I can handle that one not that I need to, but I'll try it just to see if I can do it. But that's pointless if I can't find a code to activate. I have no real good idea how to make codes other than to look for JALs from certain labels and maybe try a 1 or 0 to turn it on or off.

I was looking around in Devil May Cry and found player_damage_check and am sure it has something to do with infinite health, but I don't know what to do from there and why. Going by the label name I get the idea that it checks to see if I was damaged or touched by something harmful or something. I noticed a guide on the codemasters site mentioned it, but I don't know what they did or why. They changed it's address to some "jr ra" thing and zeroed out the address after it. Why does that work?

Then I saw some stop time code for the game there too. Once they found the label timer_set they jumped referers until they came across one that mentioned loadword (lw) and said it was a dead give away. Why's lw a dead give away that you change the value of that address to get the code?
I don't know how this stuff works at all.

What are some very obvious things? Like what are some things that you don't do and why, and what are some things that are obvious and why?


I was going to tamper with Devil May Cry for a starter on this stuff. I was looking at labels like "price_data_easy" "find_enemy_weak_point" "item_limit_tbl_hard" "Pl_debug_skl_on" "Pl_devil_off", and was wondering what "Mysterious_dance_blur" and "pEm_zelda" were. They also spelled pause wrong in their labels as "puase" or else that's some weird computer term I've never heard.


I was going to see how things worked because I have a cobebreaker and go to www.cmgsccc.com for my codes. I noticed I can't find crap from the addresses their codes use like infinite health being 1A8F0B52 00000BB8. There's nothing at 008F0B52 or 000F0B52 or 0A8F0B52 so I can't learn a thing from codes on their site. Do codebreaker codes have some sort of encryption because I haven't seen anything mentioned other than AR has encryption and Xploder doesn't. I have a version 9.2 or 9.3, can't remember.



In all honesty I just wanted to find a missing thing or 2 that aren't there for devil may cry like CB's "Allow Usage Of Sparda Devil Trigger" code doesn't have the fireballs with it so I wanted to find that and make it work.
I also can't learn the codes by seeing what's on your website because I don't have any of them games.

[Viper187]

1. They changed that to JR RA and NOP becauses that's where the player damage routine begins. JR RA being there causes it to return to wherever it was called from, skipping the player damage stuff.

2. Yes, they're encryped. Some codes (usually the address higher in RAM), only modify the random memory values. Assembly codes are the only thing you can look up in PS2DIS. They're typically 32-bit codes. Once you get more into assembly, you'll have an easier time spotting codes that are likely to be ASM hacks.

3. I always wanted a complete code for that devil trigger too. If I could get a hold of a copy of the SLES(?) file from the PAL version, I could probably port these:

Devil May Cry (PAL)

Sparda Sword Devil Trigger Activator
20138B70 00000000
102D4BAC 00000003
102D4BBC 00000003
202C1C10 03E00008
202C04E4 00000000

Ultimate Devil Trigger (Anmerkung!)
D07538C2 0000FDDF
005C79F0 00000003
D07538C2 0000FD7F
005C79F0 00000000
D07538C2 0000FDEF
005C79F0 00000001
D07538C2 0000FDBF
005C79F0 00000004