Thread: GBA multiplayer over DS wireless

I just had an urge to look into anything that could allow me to play my multiplayer GBA games over wireless with another DS doing the same thing, but I haven't found anything so here I am asking about it.

I have a CycloDS Evolution, an EZflash 3-in-1, and several multiplayer-capable GBA games, which should be more than enough for such a thing to work. I have my games backed up and I use them with the 3-in-1 for convenience and for trying new things, and no I don't pirate or cheat in multiplayer.

It seems like a somewhat simple task considering that GBA games can be booted with a graphical border around it, which I think is a decent indicator that extra DS hardware functions can be used while playing a GBA game. I don't know all the in-depth stuff, but I'm assuming all that is needed is a DS application that configures and enables the DS wireless/wi-fi which is then hooked to the GBA multiplayer connection when booting from the GBA slot.

Playing multiplayer DS games over wi-fi which are designed only for the proprietary wireless protocol would also be very awesome, but that's not my focus of this thread. Such a thing might require that the games be backups and can't be run from their original cards, unless perhaps the application works like the NDS Backup Tool where the flash card is replaced with the game card after starting the utility.

So, does anyone happen to know if anything like this is available or if anyone is working on it or wants to develop it? If not maybe you can post your support for it to encourage developers to pick it up.
Pilot_51 is offline Report Post Reply With Quote

The *.ds.gba format is nothing special. It's the exact same as the *.nds file but with a small header attached to the front of it. This is needed so that the program can be flashed to traditional *.gba flash carts (Flash2Advance, X-rom, etc). It doesn't switch to GBA mode at any time.

Yes, the DS has control over both the ARM7 and ARM9. The main problem is that the ARM7 functions in two entirely separate ways depending on whether you're in DS mode or GBA mode. For example, there are some essential trig functions the ARM7 can do in GBA mode but not in DS mode, and the same goes the other way around. In DS mode, the ARM7 mostly only controls the touchscreen, speakers, and wifi (among other things), while in GBA mode it handles EVERYTHING.

Exophase (the one who emulated the GBA on the PSP) has stated that while it might be possible to translate GBA ARM7 commands into DS commands on the fly, it would be very buggy and prone to incompatibilities and graphical glitches. The only other alternative would be a purely software-based renderer, which would be slow as molasses if it was ever created.

Stephen Stair, the guy behind the homebrew DS wifi library, has already attempted DS tunneling; that is, using standard wifi in place of local ad-hoc traffic for games that only have local wireless options. He gave up after a while, as the DS has very strict timing requirements when using local wireless, whereas when using wifi it accommodates for slower transfer times and missed packets.