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#pragma once
#include "stdafx.h"
#include "SquareChannel.h"
#include "BaseExpansionAudio.h"
#include "CPU.h"
#include "Console.h"
#include "MemoryManager.h"
class MMC5Square : public SquareChannel
{
int8_t _currentOutput;
private:
virtual void InitializeSweep(uint8_t regValue) override
{
//"$5001 has no effect. The MMC5 pulse channels will not sweep, as they have no sweep unit."
}
public:
MMC5Square(shared_ptr<Console> console) : SquareChannel(AudioChannel::MMC5, console, nullptr, false)
{
_currentOutput = 0;
_isMmc5Square = true;
}
int8_t GetOutput()
{
return _currentOutput;
}
void RunChannel()
{
if(_timer == 0) {
_dutyPos = (_dutyPos - 1) & 0x07;
//"Frequency values less than 8 do not silence the MMC5 pulse channels; they can output ultrasonic frequencies."
_currentOutput = _dutySequences[_duty][_dutyPos] * GetVolume();
_timer = _period;
} else {
_timer--;
}
}
};
class MMC5Audio : public BaseExpansionAudio
{
private:
MMC5Square _square1;
MMC5Square _square2;
int16_t _audioCounter;
int16_t _lastOutput;
bool _pcmReadMode;
bool _pcmIrqEnabled;
uint8_t _pcmOutput;
protected:
void StreamState(bool saving) override
{
BaseExpansionAudio::StreamState(saving);
SnapshotInfo square1{ &_square1 };
SnapshotInfo square2{ &_square2 };
Stream(square1, square2, _audioCounter, _lastOutput, _pcmReadMode, _pcmIrqEnabled, _pcmOutput);
}
void ClockAudio() override
{
_audioCounter--;
_square1.RunChannel();
_square2.RunChannel();
if(_audioCounter <= 0) {
//~240hz envelope/length counter
_audioCounter = _console->GetCpu()->GetClockRate(_console->GetModel()) / 240;
_square1.TickLengthCounter();
_square1.TickEnvelope();
_square2.TickLengthCounter();
_square2.TickEnvelope();
}
//"The sound output of the square channels are equivalent in volume to the corresponding APU channels"
//"The polarity of all MMC5 channels is reversed compared to the APU."
int16_t summedOutput = -(_square1.GetOutput() + _square2.GetOutput() + _pcmOutput);
if(summedOutput != _lastOutput) {
_console->GetApu()->AddExpansionAudioDelta(AudioChannel::MMC5, summedOutput - _lastOutput);
_lastOutput = summedOutput;
}
_square1.ReloadCounter();
_square2.ReloadCounter();
}
public:
MMC5Audio(shared_ptr<Console> console) : BaseExpansionAudio(console), _square1(console), _square2(console)
{
_audioCounter = 0;
_lastOutput = 0;
_pcmReadMode = false;
_pcmIrqEnabled = false;
_pcmOutput = 0;
}
uint8_t ReadRegister(uint16_t addr)
{
switch(addr) {
case 0x5010:
//TODO: PCM IRQ
return 0;
case 0x5015:
uint8_t status = 0;
status |= _square1.GetStatus() ? 0x01 : 0x00;
status |= _square2.GetStatus() ? 0x02 : 0x00;
return status;
}
return _console->GetMemoryManager()->GetOpenBus();
}
void WriteRegister(uint16_t addr, uint8_t value)
{
switch(addr) {
case 0x5000: case 0x5001: case 0x5002: case 0x5003:
_square1.WriteRAM(addr, value);
break;
case 0x5004: case 0x5005: case 0x5006: case 0x5007:
_square2.WriteRAM(addr, value);
break;
case 0x5010:
//TODO: Read mode & PCM IRQs are not implemented
_pcmReadMode = (value & 0x01) == 0x01;
_pcmIrqEnabled = (value & 0x80) == 0x80;
break;
case 0x5011:
if(!_pcmReadMode) {
if(value != 0) {
_pcmOutput = value;
}
}
break;
case 0x5015:
_square1.SetEnabled((value & 0x01) == 0x01);
_square2.SetEnabled((value & 0x02) == 0x02);
break;
}
}
};