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Coding > GBA as a GCN controller

#58963 - pete - Thu Oct 27, 2005 5:29 pm

Hi there!

I've been pondering on the question for quite a while now, but the more I think about it, the more I realize it isnt't as trivial as I thought. I'd like to write a GBA app that turns it into a general, configurable GCN controller (due to the fact that the former has less buttons) using the link cable. I thought it would make for a sweet introductory link port project, but as I gathered the required documentation, it seems like I'll need a hand with this after all.

What comm mode should I use, UART? How do I answer the controller probe sequence, since the GCN sends 8 low bits followed by a high stop bit (9 bits in all)? Does the link cable have a circuit that takes care of that? Perhaps someone has already done that before? Is this possible at all?

Alright, that's enough questions for now. Thanks for any help!

EDIT: Here's where I got the GCN controller protocol: http://www.int03.co.uk/crema/hardware/gamecube/gc-control.htm

#59275 - pete - Sun Oct 30, 2005 10:48 pm

Awww, come on, I can't be the only one to have thought of that? There gotta be someone out there either as curious or as cheap as I am! Making a rom that lets you map your GBA buttons to GCN ones shouldn't be that difficult...

No one interested in joining forces for this project? <:/

#59288 - tepples - Mon Oct 31, 2005 3:47 am

I believe the GBA hardware has some sort of "JOYBUS mode" that handles the ADB/N64/GCN style pulse-width modulation for you. Has this been cracked?
_________________
-- Where is he?
-- Who?
-- You know, the human.
-- I think he moved to Tilwick.

#59614 - pete - Wed Nov 02, 2005 10:05 pm

Oh, yeah, I do remember reading about JOYBUS somewhere. Thanks a lot for the tip, I'll have look in that direction.

By the way, for those interested in the GBA internals, the no$gba emulator documentation is THE way to go. There's an awesome lot of tasty info in there. But again, I suppose most of you already knew that. :)

Later!