bsnes/gb/apu/apu.cpp

117 lines
3.5 KiB
C++

#include <gb/gb.hpp>
#define APU_CPP
namespace GameBoy {
#include "square1/square1.cpp"
#include "square2/square2.cpp"
#include "wave/wave.cpp"
#include "noise/noise.cpp"
#include "master/master.cpp"
#include "serialization.cpp"
APU apu;
void APU::Main() {
apu.main();
}
void APU::main() {
while(true) {
if(scheduler.sync == Scheduler::SynchronizeMode::All) {
scheduler.exit(Scheduler::ExitReason::SynchronizeEvent);
}
if(sequencer_base == 0) { //512hz
if(sequencer_step == 0 || sequencer_step == 2 || sequencer_step == 4 || sequencer_step == 6) { //256hz
square1.clock_length();
square2.clock_length();
wave.clock_length();
noise.clock_length();
}
if(sequencer_step == 2 || sequencer_step == 6) { //128hz
square1.clock_sweep();
}
if(sequencer_step == 7) { //64hz
square1.clock_envelope();
square2.clock_envelope();
noise.clock_envelope();
}
sequencer_step++;
}
sequencer_base++;
square1.run();
square2.run();
wave.run();
noise.run();
master.run();
hipass(master.center, master.center_bias);
hipass(master.left, master.left_bias);
hipass(master.right, master.right_bias);
interface->audioSample(master.left, master.right);
clock += cpu.frequency;
if(clock >= 0 && scheduler.sync != Scheduler::SynchronizeMode::All) co_switch(scheduler.active_thread = cpu.thread);
}
}
void APU::hipass(int16& sample, int64& bias) {
bias += ((((int64)sample << 16) - (bias >> 16)) * 57593) >> 16;
sample = sclamp<16>(sample - (bias >> 32));
}
void APU::power() {
create(Main, 2 * 1024 * 1024);
for(unsigned n = 0xff10; n <= 0xff3f; n++) bus.mmio[n] = this;
for(auto& n : mmio_data) n = 0x00;
sequencer_base = 0;
sequencer_step = 0;
square1.power();
square2.power();
wave.power();
noise.power();
master.power();
}
uint8 APU::mmio_read(uint16 addr) {
static const uint8 table[48] = {
0x80, 0x3f, 0x00, 0xff, 0xbf, //square1
0xff, 0x3f, 0x00, 0xff, 0xbf, //square2
0x7f, 0xff, 0x9f, 0xff, 0xbf, //wave
0xff, 0xff, 0x00, 0x00, 0xbf, //noise
0x00, 0x00, 0x70, //master
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, //unmapped
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, //wave pattern
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, //wave pattern
};
if(addr == 0xff26) {
uint8 data = master.enable << 7;
if(square1.enable) data |= 0x01;
if(square2.enable) data |= 0x02;
if( wave.enable) data |= 0x04;
if( noise.enable) data |= 0x08;
return data | table[addr - 0xff10];
}
if(addr >= 0xff10 && addr <= 0xff3f) return mmio_data[addr - 0xff10] | table[addr - 0xff10];
return 0xff;
}
void APU::mmio_write(uint16 addr, uint8 data) {
if(addr >= 0xff10 && addr <= 0xff3f) mmio_data[addr - 0xff10] = data;
if(addr >= 0xff10 && addr <= 0xff14) return square1.write (addr - 0xff10, data);
if(addr >= 0xff15 && addr <= 0xff19) return square2.write (addr - 0xff15, data);
if(addr >= 0xff1a && addr <= 0xff1e) return wave.write (addr - 0xff1a, data);
if(addr >= 0xff1f && addr <= 0xff23) return noise.write (addr - 0xff1f, data);
if(addr >= 0xff24 && addr <= 0xff26) return master.write (addr - 0xff24, data);
if(addr >= 0xff30 && addr <= 0xff3f) return wave.write_pattern(addr - 0xff30, data);
}
}