SID player for the 32X
Posted: Wed Oct 09, 2013 5:47 pm
Here's another small project of mine. I've taken a SID player I wrote a few months back and ported it to the 32X:
ROM download
YouTube video (the video turned out a bit loud, so I recommend not watching it on full volume)
Pretty much everything is done on the slave SH2: it emulates both the 6510 and 6581, does the audio mixing, and the DMA:ing of audio data to the PWM circuit. Everything is pure C (except the final conversion from mono to stereo and lowpass-filtering), so there's certainly room for improvement, although it already seems to run fast enough.
The emulation isn't the most accurate. For example I don't emulate the SID filters; nor do I emulate the CIA or the VIC-II or any of their interrupts (I always call the PLAY routine at 50 Hz). Still, that works well enough for a fair amount of songs.
ROM download
YouTube video (the video turned out a bit loud, so I recommend not watching it on full volume)
Pretty much everything is done on the slave SH2: it emulates both the 6510 and 6581, does the audio mixing, and the DMA:ing of audio data to the PWM circuit. Everything is pure C (except the final conversion from mono to stereo and lowpass-filtering), so there's certainly room for improvement, although it already seems to run fast enough.
The emulation isn't the most accurate. For example I don't emulate the SID filters; nor do I emulate the CIA or the VIC-II or any of their interrupts (I always call the PLAY routine at 50 Hz). Still, that works well enough for a fair amount of songs.
