OPNAcog - The sound of the NEC PC-88/PC-98 in a cog!
Wuerfel_21
Posts: 4,507
It is yet again time for a sound chip emulator cog! This time it's the YM2608 (and by extension YM2203). Yes, this is just a small variation on the YM2612 (and thus the OPN2cog), but I had it sitting around semi-unfinished for a while, so I'm properly posting it now (it's on its way into the OBEX Git as we speak)
As said, mostly the same as OPN2cog, but for YM2608.
In particular, that means:
- AY-style square waves instead of SN-style ones (the SN not really being a part of the YM2612 to begin with)
- Rhythm channels! (I even modified the Spin API demo to use them!)
- No ADPCM channel (isn't actually hooked up in NEC systems and later integrated chips don't even have the circuit)
- No DAC distortion/multiplexing
- Higher clock speeds needed
Hmm, by total number I've now made the same number of chip emulators as @Ahle2, but does this really count as a separate one from OPN2?
Comments
Yeah, about that... Still not merged: https://github.com/parallaxinc/propeller/pull/253