mirror of https://github.com/bsnes-emu/bsnes.git
30 lines
700 B
C++
30 lines
700 B
C++
auto APU::DMA::run() -> void {
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if(!r.enable) return;
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if(r.rate == 0 && ++s.clock < 768) return; // 4000hz
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if(r.rate == 1 && ++s.clock < 512) return; // 6000hz
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if(r.rate == 2 && ++s.clock < 256) return; //12000hz
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if(r.rate == 3 && ++s.clock < 128) return; //24000hz
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s.clock = 0;
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uint8 data = bus.read(s.source);
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if(r.direction == 0) s.source++;
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if(r.direction == 1) s.source--;
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if(r.target == 0) {
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apu.channel2.r.volumeRight = data.bits(0,3);
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apu.channel2.r.volumeLeft = data.bits(4,7);
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} else {
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apu.channel5.s.data = data;
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}
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if(--s.length) return;
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if(r.loop) {
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s.source = r.source;
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s.length = r.length;
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} else {
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r.enable = false;
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}
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}
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