How to convert Psx Game Shark codes to ROM patch

[leo_core]

I wonder how can I convert an address code for Game Shark to ROM address, eg:

I have a code:

Mortal Kombat Trilogy
Infinite Energy P1 8003219E 00A6

How could I apply this change directly in the ROM (ISO) file?
What is the address of offset?
Thanks in advance.

[rimsky82]

GameSharks manipulate the system's RAM, so there is no way to directly use the address to patch the iso. You would have to debug the psx game, and modify the executable to achieve the desired effect.

Its the same principle as the other oft-asked question about converting par to game genie codes.

[leo_core]

GameSharks manipulate the system's RAM, so there is no way to directly use the address to patch the iso. You would have to debug the psx game, and modify the executable to achieve the desired effect.

Its the same principle as the other oft-asked question about converting par to game genie codes.

Hi rimsky82, thanks for reply.
The RAM data that are manipulate by GameShark are loaded from the iso, so I thought maybe there was a way to convert the RAM address codes to ROM offset address. So I could apply directly changes in iso file, using a hex editor (romhack).
Is there any way to do this conversion?

[rimsky82]

Oh, well in that case...

GameSharks manipulate the system's RAM, so there is no way to directly use the address to patch the iso. You would have to debug the psx game, and modify the executable to achieve the desired effect.

Its the same principle as the other oft-asked question about converting par to game genie codes.

[Lazy Bastard]

Heh.

But seriously, 'RAM data' isn't loaded from the ISO or disc. It's loaded from the system's RAM (whether the system be a PC or a real PSX). The PSX (or emulator) loads the disc (or ISO), runs various executables and loads various files into memory. As these files are executed or loaded, they change the system's current state, and as various things occur in the game, the system's state continues to change. The current state of the entire system at any given time is contained in the RAM (and registers, but that's for another conversation).

Hence, there is no direct conversion between RAM codes and actual game data files. We're not saying this to be naysayers, and you're welcome to look around the net for other information (or to simply read through our library on the main page) - it just isn't possible. You can, however, do as rimsky82 said, and perform some debugging/disassembly to figure out what needs to be changed.

[leo_core]

Heh.

But seriously, 'RAM data' isn't loaded from the ISO or disc. It's loaded from the system's RAM (whether the system be a PC or a real PSX). The PSX (or emulator) loads the disc (or ISO), runs various executables and loads various files into memory. As these files are executed or loaded, they change the system's current state, and as various things occur in the game, the system's state continues to change. The current state of the entire system at any given time is contained in the RAM (and registers, but that's for another conversation).

Hence, there is no direct conversion between RAM codes and actual game data files. We're not saying this to be naysayers, and you're welcome to look around the net for other information (or to simply read through our library on the main page) - it just isn't possible. You can, however, do as rimsky82 said, and perform some debugging/disassembly to figure out what needs to be changed.

You explained everything! Thank you, I was trying improbable things here ... but now I understand why. Really thanks!

rimsky82,
Thanks again for reply =)