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Hardware > Using Pokemon Cartriges for homebrew games

#22885 - MonkeyBoy666 - Wed Jun 30, 2004 8:18 pm

Ok i here that Pokemon Ruby and Saphire had some sort of errors that required an update.

so apparently they added the update to the Pokemon Collosieum Game for the game cube. so that when you connect your Pokemon Ruby game to a gamecube running Pokemon Collosieum it installes the update.

Am i just imagining this or could we do the same thing when the pokemon cartriges only with a totally different game

or didi this nintendo update just change the save files or somethign.

I some times ramble so to refesh:
Can we use the pokemon ruby cartrige to save our own games because nintendo did this with there own update?

Also i assume nintendo didn't know that there was any errors when it came out (it wouldn't suprize me it they did) so wouldn't they use the same cartrage as the use for every other game so wouldn't this mean it is possible for every game.

Am i getting my hopes up or could there be something behind this.

#22899 - tepples - Wed Jun 30, 2004 10:24 pm

MonkeyBoy666 wrote:
or didi this nintendo update just change the save files or somethign.

Most likely.

Quote:
Can we use the pokemon ruby cartrige to save our own games because nintendo did this with there own update?

If the update to the savegames exploited a buffer overflow in the GBA software, yes. If not, no.

This brings me to a more general question: Which games have exploitable buffer overflows that would let an attacker store code in the savegame area and then have the game load it into RAM and jump to it?

However, this is all academic to a point because if you can get savegames on and off a GBA Game Pak, you can probably just multiboot the GBA and run your code directly that way.
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#22901 - ampz - Wed Jun 30, 2004 10:29 pm

The "update" could also be some setting in the RTC.

#22911 - dagamer34 - Thu Jul 01, 2004 12:45 am

ampz wrote:
The "update" could also be some setting in the RTC.


Yeah, that's what I think it is. Something to do with an error in the RTC that Pokemon Coliseum fixes.
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#22917 - MonkeyBoy666 - Thu Jul 01, 2004 1:25 am

thanks

what you said made sense

#22925 - MumblyJoe - Thu Jul 01, 2004 8:02 am

Yeah, from what people have figured out, the fixes in Colloseum and Channel fix something where berries dissapear by changing the RTC. An interesting note is that this also has served as pretty effective copy protection, only one flash card on the market is known to link up so far :P

Regardless, its not too useful for launching homebrew games... but it could possibly be useful for writing trainers or cheat patches or something for the pokemon games, seeing as I assume the code gets loaded and ran after a few other things and you could call functions that pokemon uses if you knew the addresses and signatures of them.
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