Hacking Games Using an Emulator

[LiquidManZero]

I can't promise this is going to be great info, but I'll try to answer any questions.

First thing, you've got to have an emulator set up and working. This is somewhat complicated matter what with all the plugins and bios images needed, and unless requested, I'm not going to say anything about how to do this.

I tend to use PSXeven, mostly because it's the only one I've gotten to work well and reliably. The basic way of extracting the RAM from a savestate is going to be pretty much the same on any emulator.

From here on down, I'll probably rewrite what I've got a bit later:

How to find the offset to the beginning of the RAM:
Assuming you've got an emulator going, and have at least one savestate for the game already... Most of the emulators have the state compressed using gzip, so you have to decompress it. You should be able to do this if you've got something like winzip, winrar, 7zip, or any decent archive program. The easy way is often to just rename the file to add at the end ".gz" and then open it with whatever is set to open those. Just extract the file where you can find it, and then open it in a hex editor...

Bleh... OK, I'm leaving some things out, I'll have to resume this a bit later... So don't complain too much right now about this, it's very much incomplete...



Random information:
1BA - Start of emulated RAM in an ePSXe savestate.

[St3ph]

Hacking Games Using an Emulator

cool.. i'm using PSXeven to hack the suikoden 2 game, but then there's a lot of black box which i don't quite understand.. so hopefully will look into it more .

[LiquidManZero]

Hacking Games Using an Emulator

Here's some interesting information. There's at least two different modern psx emulators with debugger functions, and one of them has breakpointing...

http://psxemulator.gazaxian.com/

Keep in mind, this sucker is probably going to be slow for most people. It also seems to requires a specific dll file, thanks to m$ being bastards.

The attached file is that dll file. If the emulator asks for it when you start it up, just put that dll in the same folder as psxfin.exe.

[ugetab]

Re: Hacking Games Using an Emulator

The file wnaspi32.dll is needed to access games from the CDROM drive. It, and INASPI32.SYS / INSTASPI.EXE can be found in the attachment. Just put it in the same folder, reopen the emulator, and it'll work.

[LiquidManZero]

Re: Hacking Games Using an Emulator

That's nice of it. Damn windows, it should have that by default if there's cd/dvdrom support.

[ugetab]

Re: Hacking Games Using an Emulator

I got into this debugger a bit, and learned some of it's quirks.

Here's the result:
Wild Arms:
Enable 'Map' Option Under Config(Assembly Hack, Same as the 'Map Select Debug Menu', but doesn't interfere with menu systems):
D00600F0 2C4E
300600FC 0001

Here's the actual information I learned about it:
When adding Breakpoints, choose Debug>Break before modifying the list. This prevents crashes. Once the list has been edited, you can go to Debug>Run and continue.

Define Breakpoints(among other things, like disassembly) using 0x# for hex numbers. This allows the numbers entered to be used. The Dos Prompt box will register errors with entering long numbers without 0x before them.

The addresses between the PSX using a Gameshark and the Debugger may be a little different in some cases. Remember to check any code modifications from the Gameshark before you deem your efforts complete.

Edit:
apparently, Gamesharks can't handle condition stacking with D0 codes. I'll just make it rely on the first one.

[LiquidManZero]

Re: Hacking Games Using an Emulator

Impressive. Good to know that the debugger on that works reasonably. If I get some time to screw around with that, I might finally be able to do some codes that were impossible to hack with a gameshark.

[St3ph]

Re: Hacking Games Using an Emulator

okie, erm, hi once again. just in case people wonder, it's me St3ph from the previous, i don't know what or where went wrong, i can't use my old ID again, so this will be my new iD

anyway, what i wanted to ask is, erm, what type of burning application do you guys use? coz i still can't get the CD image to my PC. got fed up , so wanted to seek help. thanks in advance.

[MathUser]

Re: Hacking Games Using an Emulator

I know Alcohol 120 is the reccomended program. I woould suggest using that.

[Deathwing Zero]

Re: Hacking Games Using an Emulator

I agree, Alcohol 120% is the best choice. But make the CD Image as bin and cue, since all emulators recognize that you shouldn't have to mount the image in a virtual CD Drive. When you make a Playstation game into a .ISO it seems to screw up some games.

Here are my settings:

Skip reading errors: Checked
All other boxes: Unchecked

Once you click next, there is an Image Format drop down menu, I changed mine to bin + cue (CDR Win Image file), but you will have the choice of Media Descriptor Format (.MDF) CDR Win Image File (.bin) Clone CD Image File (.img) and Standard ISO (.iso).

I prefer .bin because all the emulators ive used recognize that format and I don't have to mount the image to play it.

[LiquidManZero]

Re: Hacking Games Using an Emulator

I don't recomend using Alcohol 120% to burn clonecd images. I've tried it several different times and it failed every single time.

One thing to keep in mind when dealing with backing up playstation games (or just dealing with disc images of them), is that the CD Audio tracks (as in, the ones you could play in a normal cd player) will generally not work in game. There's a bit of a difference in the location(s) of something after a psx game is imaged, and it's enough to throw most games out of whack.

[Deathwing Zero]

Re: Hacking Games Using an Emulator

I have that same problem. I only use Alcohol 120% to make CD Images and burn .bin/.cue, .iso and .mds/.mdf.

[St3ph]

Re: Hacking Games Using an Emulator

okie, i've got it to work already.. i load my game, played it, everything was fine, but there's one thing which i couldn't find and that is, where to set my gameshark or address? i don't quite understand , and it's completely different from PSX Even

[Deathwing Zero]

Re: Hacking Games Using an Emulator

You will need a gameshark CD image. I only have gameshark 5.0 cd. I can host it for you if you want it, but GS 5.0 doesn't like "50" codes, so they'll need to be converted.

If you are using PCSX, you can still use PEC.

Hope that helps out

[LiquidManZero]

Re: Hacking Games Using an Emulator

I don't understand why emulators tend to have horrible code usage support. I'm sure it's not that insanely difficult to do, and a lot of people would appreciate it.