Mesen/Core/APU.cpp

#pragma once

#include "stdafx.h"
#include "APU.h"
#include "CPU.h"

APU* APU::Instance = nullptr;
IAudioDevice* APU::AudioDevice = nullptr;

APU::APU()
{
	APU::Instance = this;

	_buf.sample_rate(APU::SampleRate);
	_buf.clock_rate(CPU::ClockRate);
	_apu.output(&_buf);

	_apu.dmc_reader(&APU::DMCRead);
	//_apu.irq_notifier(&APU::IRQChanged);

	_outputBuffer = new int16_t[APU::SamplesPerFrame];
}

APU::~APU()
{
	delete[] _outputBuffer;
}

void APU::Reset()
{
	_apu.reset();
}

int APU::DMCRead(void*, cpu_addr_t addr)
{
	return APU::Instance->ReadRAM(addr);
}

uint8_t APU::ReadRAM(uint16_t addr)
{
	switch(addr) {
		case 0x4015:
			return _apu.read_status(5);
			break;
	}

	return 0;
}

void APU::WriteRAM(uint16_t addr, uint8_t value)
{
	_apu.write_register(5, addr, value);
}

bool APU::Exec(uint32_t executedCycles)
{
	/*if(APU::Instance->_apu.earliest_irq() == Nes_Apu::irq_waiting) {
		CPU::SetIRQFlag();
	}*/
	_apu.end_frame(executedCycles);
	_buf.end_frame(executedCycles);
	
	// Read some samples out of Blip_Buffer if there are enough to fill our output buffer
	uint32_t availableSampleCount = _buf.samples_avail();
	if(availableSampleCount >= APU::SamplesPerFrame) {
		size_t sampleCount = _buf.read_samples(_outputBuffer, APU::SamplesPerFrame);
		APU::AudioDevice->PlayBuffer(_outputBuffer, sampleCount * BitsPerSample / 8);

		return true;
	}

	return false;
}