SID player for the 32X

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mic_
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SID player for the 32X

Post by mic_ » 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.

TechnoZealot
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Post by TechnoZealot » Sun Oct 20, 2013 10:04 pm

Very nice! :D

haroldoop
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Post by haroldoop » Mon Oct 21, 2013 1:16 am

Cool. :)

mic_
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Post by mic_ » Mon Oct 21, 2013 7:27 am

I'm planning to make a music disk out of this. It's mostly done, except that I need to create graphics for UI. Hopefully I'll find time for that in the next few weeks.

mic_
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Post by mic_ » Sat Nov 02, 2013 9:24 am

Alright, here's the multi-song version:

ROM + instructions
YouTube video

While I was at it, I modified the mixing a bit. I now output 24 kHz mono instead of 22.05 kHz stereo (the SID chip doesn't have any left/right balance anyway). And the output is no longer super-loud.

mic_
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Post by mic_ » Sun Nov 03, 2013 4:30 pm

Another update, this time with some bugfixes and UI additions:

ROM + instructions
YouTube video

I've also released the source code.

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