Patching Gameshark to N64 ROMs

[Nayib]

Hey, guys. I kinda need help with this.

I want to patch a gameshark code, specifically this one:

(Enable All Cheats) - Diddy Kong Racing

810EB22E FFFF
810EB22C 10FF

I want this to be permanent on the ROM. I've read this is possible with Super Mario 64, and there's probably some process to doing it that I'm not aware of.

If someone could explain to me how this is done, then I'd be grateful!

[The Colonel]

I know you can enter new codes into old ROMs, not sure about GS codes.

[SubDrag]

It's not that complicated but you need to know assembly. There are multiple ways but simplest way is the function to get cheat data just hardcode in ram to return true or FF and move to rom in equivalent spot. You can use static analysis of ram dump using ida pro or my disassembler on goldeneye vault of all loads of that spot, or easier yet is use nemu and breakpoint read on cheat spot. Ill cover this in hacking class 6 but it will be a little while till out. Use renegade 64 to assemble replacement lines. You might need to redo crc on rom after change using rn64crc

[Nayib]

Umm... Subdrag. I'm sure that makes complete and total sense... But I have NO IDEA what it means.

I guess Hacking Class 6 will save me on this one.

[XeRo9009]

Originally Posted by SubDrag

It's not that complicated but you need to know assembly. There are multiple ways but simplest way is the function to get cheat data just hardcode in ram to return true or FF and move to rom in equivalent spot. You can use static analysis of ram dump using ida pro or my disassembler on goldeneye vault of all loads of that spot, or easier yet is use nemu and breakpoint read on cheat spot. Ill cover this in hacking class 6 but it will be a little while till out. Use renegade 64 to assemble replacement lines. You might need to redo crc on rom after change using rn64crc

I hope this isn't too much to ask... but SubDrag! Is it possible for you or anyone else on the board with great N64 hacking skills (such as Coolboyman) to do this on the Banjo-Tooie rom with Bottle's Revenge enabled? The reason I ask is because the 64drive (new flashcart for the N64) doesn't do Gameshark codes and those without a Gameshark won't be able to access the mode on original hardware.

Of course I have an original cart and can buy a Gameshark, but those using the flash cart for the soon-to-be-compatible Banjo-Tooie rom will have no way to access this mode even with a Gameshark AFAIK.

[SubDrag]

Here are the spots in BT you would want to change in RAM addresses to enable Bottles Revenge in NTSC:
800D394C 24020001
800D3960 24020001
800D3938 24020001

80030080 240E0002
8003001C 240E0002
800300D8 240C0002
80030148 240F0002



Unfortunately, the bad news is I can't find the compressed file containing these ASM instructions, and I know some are encrypted, maybe in those.