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bsnes/higan/gba/cpu/keypad.cpp

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Update to v103r07 release. byuu says: Changelog: - gba/cpu: massive code cleanup effort - gba/cpu: DMA can run in between active instructions¹ - gba/cpu: added two-cycle startup delay between DMA activation and DMA transfers² - processor/spc700: BBC, BBC, CBNE cycle 4 is an idle cycle - processor/spc700: ADDW, SUBW, MOVW (read) cycle 4 is an idle cycle ¹: unfortunately, this causes yet another performance penalty for the poor GBA core =( Also, I think I may have missed disabling DMAs while the CPU is stopped. I'll fix that in the next WIP. ²: I put the waiting counter decrement at the wrong place, so this doesn't actually work. Needs to be more like this:    auto CPU::step(uint clocks) -> void {      for(auto _ : range(clocks)) {        for(auto& timer : this->timer) timer.run();        for(auto& dma : this->dma) if(dma.active && dma.waiting) dma.waiting--;        context.clock++;      }      ...    auto CPU::DMA::run() -> bool {      if(cpu.stopped() || !active || waiting) return false;      transfer();      if(irq) cpu.irq.flag |= CPU::Interrupt::DMA0 << id;      if(drq && id == 3) cpu.irq.flag |= CPU::Interrupt::Cartridge;      return true;    } Of course, the real fix will be restructuring how DMA works, so that it's always running in parallel with the CPU instead of this weird design where it tries to run all channels in some kind of loop until no channels are active anymore whenever one channel is activated. Not really sure how to design that yet, however.
2017-07-05 05:29:27 +00:00
auto CPU::Keypad::run() -> void {
//lookup table to convert button indexes to Emulator::Interface indexes
static const uint lookup[] = {5, 4, 8, 9, 3, 2, 0, 1, 7, 6};
if(!enable) return;
bool test = condition; //0 = OR, 1 = AND
for(auto n : range(10)) {
if(!flag[n]) continue;
bool input = platform->inputPoll(0, 0, lookup[n]);
if(condition == 0) test |= input;
if(condition == 1) test &= input;
}
if(test) cpu.irq.flag |= CPU::Interrupt::Keypad;
}