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Audio > Streaming music from External Memory to a (modded) Gameboy

#34313 - enliteneer - Mon Jan 17, 2005 6:02 pm

Ok not really a "modded" Gameboy, but I have an Xport2 (www.charmedlabs.com") that has 16MB of RAM. that Ive got plugged into the GBA.

My goal is to decode AAC externally (on the Xport) but play it through the GBA. Since the audio would already be uncompressed ready-to-go, could it be placed in the GBA's audio buffer directly or would the data still need to be converted to another (GBA) format at runtime?

Any ideas?

#34318 - tepples - Mon Jan 17, 2005 9:10 pm

The GBA native audio format is signed 8-bit mono PCM; stereo uses two separate streams. You can probably easily coax your AAC decoder into outputting this format.
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#34536 - enliteneer - Fri Jan 21, 2005 2:09 am

Fortunately, the ouput is PCM...

but it seems most of the (source code) examples/demos Ive seen convert the wav file to an .h file and compile it with the mainline code and then access it as you would any variable...

BUT...

in general, I just need to read the wav data into local memory (RAM) and then send it to the sound chip, correct? Would that cause any syncing problems between how fast I read from external and write out to the audio?