Official Nintendo Game Boy Emulator for Nintendo 64 (Pokémon Stadium)

[Mezmorize]

My EverDrive 64 finally showed up yesterday, which was perfect timing for my birthday. Today I finally got a chance to play around with it and test out one of the accessories I had bought for the N64, the Transfer Pak. I picked it up for a mere four dollars because it was being sold as broken/as is because it was untested by the seller. The reason I bought it was because of what I read from Wikipedia about the two Pokémon Stadium games. For example, with the first Pokémon Stadium game: At the GB Tower, the player can play Pokémon Red, Blue, or Yellow on the Nintendo 64 using the Transfer Pak.

I don't own any of those Game Boy games, but do own a flash cartridge for Game Boy. After testing it out with Pokémon Blue (the only Pokémon game I've ever really played), I wondered if I would be able to make it boot any other Game Boy games.

I first picked Wario Land II to test out because it was the same size ROM as Pokémon Blue as well as the same cartridge type. Just by changing the title of the game in the header to match Pokémon Blue and then fixing the checksum, I was able to get it to boot:

Awesome, even the Super Game Boy features were working! But unfortunately, after the intro it errors out when the N64 tries to save to the cartridge.

As a second test, I tried the non Super Game Boy game Super Mario Land. Had to do quite a few modifications to get this one working, the usual title + checksum modification wasn't enough. After changing the Destination Code (0x14A=01 for non Japanese) the game finally attempted to boot, but that still was not enough. Finally, I changed the cartridge type settings in the header as well as padded the game to 1MB, and it finally also booted up.

It soon gave an error about saving, just like Wario did. But, after simply removing the Game Boy cartridge from the Transfer Pak and re-inserting it, the game proceeded to play!

And that's about as far as my testing has came.
Still haven't tried a Game Boy Color game, nor have I tested out the potentially updated emulator inside the N64 game Pokémon Stadium 2.

[olala]

there were nice mod dood, anyho hapy bday mez
dood

[Hacc]

U Got Everything To "Accurately" Boot? (riPHP). Good job!

[Mezmorize]

I still haven't got around to trying the second game, or a Game Boy Color game >.<
Really hope some good N64 hacker will remove the checks from the game, so non-modified ROMS (another words original cartridges) will work too.

I did try one more Game Boy game since I posted the above, which is my favorite Game Boy Game: Final Fantasy Adventure. It had no problems at all and unlike the previous two games I tried, it never gave any type of error about saving. Now that I think about it, I have yet to reboot it and see if it did indeed save though.

I should probably re-post this somewhere else besides the EverDrive forums to try to find someone who could hack Pokemon Stadium.

Thanks for the links Hacc, I did see the one by ugetab after I created this thread. Just like Hybrid mentioned, if the checksum of the Game Boy game is bad, Pokemon Stadium will not get past the first screen. That's kind of a good thing, it proves that the emulator is not checking for the specific Pokemon checksums, just Game Boy in general (real hardware won't boot a game with a bad checksum either).

The first line of ugetab's code might be bypassing one of the checks, but the rest (far as I could tell) are just making it seem like there is Pokemon Red savedata on the cartridge. As you can see in my video's, that don't really matter. In my video it shows ???? and will still boot the cartridge. The most important checks would be 1. Correct checksum 2. Pokemon title in the header 3. Non Japanese region game.

I won't have a chance to do anymore testing until further in the week, likely Wednesday.

Edit:
Oh yeah, and in my initial test if the game was less than 1MB, the transfer would error out. Guess the emulator thinks it's not getting the full game. But after padding the two smaller games to 1MB, they would boot up properly. So that would be a fourth important check.