Oki ADPCM conversion to other chips?

superdeadite · Post by **superdeadite** » 2023-01-21, 12:00:56

I know absolutely nothing about programming. I'm just an MSX user that loves VGMPlay. Was wondering if there is an easy way to convert Oki ADPCM data to an MSX friendly format such as MSX-Audio or OPL4? Thanks for reading.

Post by **ValleyBell** » 2023-01-22, 10:00:19

I don't think there are any tools that can do that right now.

In theory:

OKIM6295 -> OPL4 should be easy to do, as both chips store a list of all possible samples at the beginning of the ROM. It just needs decompression of the ADPCM samples.
OKIM6295 -> MSX-Audio won't work. (4 channels > 1 channel)
OKIM6258 -> OPL4/MSX-Audio may be difficult due to the chip using realtime streaming (like the YM2612 PCM channel)

superdeadite · Post by **superdeadite** » 2023-01-22, 19:26:14

ValleyBell wrote:I don't think there are any tools that can do that right now.

In theory:

OKIM6295 -> OPL4 should be easy to do, as both chips store a list of all possible samples at the beginning of the ROM. It just needs decompression of the ADPCM samples.

OKIM6295 -> MSX-Audio won't work. (4 channels > 1 channel)

OKIM6258 -> OPL4/MSX-Audio may be difficult due to the chip using realtime streaming (like the YM2612 PCM channel)

Thanks for the info. OKIM6295 to OPL4 alone would be amazing as that would open up a lot more arcade games for MSX playback.

Tiny-Yarou, a cool Japanese dude did make a custom patch for the MSX Bosconian to use the X68000 version music using YM2151 + MSX-Audio, but of course that's using his own custom code, and the end result is impressive but not perfect. Now if only I wasn't a complete coding moron.

andlabs · Post by **andlabs** » 2023-01-28, 17:09:58

superdeadite wrote:using YM2151

Congratulations to this hack for being the first MSX game ever to use the SFG modules for music. Do you have a link? I'm curious about running this on real hardware now. (And I have all three MSX-AUDIO modules and an FM-PAC as well, in case one is also needed.)

superdeadite · Post by **superdeadite** » 2023-01-28, 19:37:17

andlabs wrote:
superdeadite wrote:using YM2151
Congratulations to this hack for being the first MSX game ever to use the SFG modules for music. Do you have a link? I'm curious about running this on real hardware now. (And I have all three MSX-AUDIO modules and an FM-PAC as well, in case one is also needed.)

Seems I am not allowed to post links. (post count too low?)
The Bosconian patch is on Tiny-Yarou's website. It can be found by searching for "DEEP! P6! DEEP! MSX!"
There are also SFG patches to add arcade OPN music to MSX versions of Kikikaikai, Scramble Formation, Legend of Kage, Commando, and Arkanoid 2.
You can find them by searching for "github toughkiddev" then in the "mglOcm/ArcadeEnhanced" folder.