mirror of
https://github.com/libretro/Mesen.git
synced 2024-12-14 04:48:42 +00:00
154 lines
3.3 KiB
C++
154 lines
3.3 KiB
C++
#pragma once
|
|
#include "stdafx.h"
|
|
#include <algorithm>
|
|
#include "Snapshotable.h"
|
|
#include "EmulationSettings.h"
|
|
#include "APU.h"
|
|
#include "BaseFdsChannel.h"
|
|
#include "ModChannel.h"
|
|
#include "BaseExpansionAudio.h"
|
|
#include "MemoryManager.h"
|
|
|
|
class FdsAudio : public BaseExpansionAudio
|
|
{
|
|
private:
|
|
const uint32_t WaveVolumeTable[4] = { 36, 24, 17, 14 };
|
|
|
|
//Register values
|
|
uint8_t _waveTable[64];
|
|
bool _waveWriteEnabled = false;
|
|
|
|
BaseFdsChannel _volume;
|
|
ModChannel _mod;
|
|
|
|
bool _disableEnvelopes = false;
|
|
bool _haltWaveform = false;
|
|
|
|
uint8_t _masterVolume = 0;
|
|
|
|
//Internal values
|
|
uint16_t _waveOverflowCounter = 0;
|
|
int32_t _wavePitch = 0;
|
|
uint8_t _wavePosition = 0;
|
|
|
|
uint8_t _lastOutput = 0;
|
|
|
|
protected:
|
|
void StreamState(bool saving) override
|
|
{
|
|
BaseExpansionAudio::StreamState(saving);
|
|
|
|
ArrayInfo<uint8_t> waveTable = { _waveTable, 64 };
|
|
SnapshotInfo volume{ &_volume };
|
|
SnapshotInfo mod{ &_mod };
|
|
|
|
Stream(volume, mod, _waveWriteEnabled, _disableEnvelopes, _haltWaveform, _masterVolume, _waveOverflowCounter, _wavePitch, _wavePosition, _lastOutput, waveTable);
|
|
}
|
|
|
|
void ClockAudio() override
|
|
{
|
|
int frequency = _volume.GetFrequency();
|
|
if(!_haltWaveform && !_disableEnvelopes) {
|
|
_volume.TickEnvelope();
|
|
if(_mod.TickEnvelope()) {
|
|
_mod.UpdateOutput(frequency);
|
|
}
|
|
}
|
|
|
|
if(_mod.TickModulator()) {
|
|
//Modulator was ticked, update wave pitch
|
|
_mod.UpdateOutput(frequency);
|
|
}
|
|
|
|
if(_haltWaveform) {
|
|
_wavePosition = 0;
|
|
UpdateOutput();
|
|
} else {
|
|
UpdateOutput();
|
|
|
|
if(frequency + _mod.GetOutput() > 0 && !_waveWriteEnabled) {
|
|
_waveOverflowCounter += frequency + _mod.GetOutput();
|
|
if(_waveOverflowCounter < frequency + _mod.GetOutput()) {
|
|
_wavePosition = (_wavePosition + 1) & 0x3F;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void UpdateOutput()
|
|
{
|
|
uint32_t level = std::min((int)_volume.GetGain(), 32) * WaveVolumeTable[_masterVolume];
|
|
uint8_t outputLevel = (_waveTable[_wavePosition] * level) / 1152;
|
|
|
|
|
|
if(_lastOutput != outputLevel) {
|
|
APU::AddExpansionAudioDelta(AudioChannel::FDS, outputLevel - _lastOutput);
|
|
_lastOutput = outputLevel;
|
|
}
|
|
}
|
|
|
|
public:
|
|
uint8_t ReadRegister(uint16_t addr)
|
|
{
|
|
uint8_t value = MemoryManager::GetOpenBus();
|
|
if(addr <= 0x407F) {
|
|
value &= 0xC0;
|
|
value |= _waveTable[addr & 0x3F];
|
|
} else if(addr == 0x4090) {
|
|
value &= 0xC0;
|
|
value |= _volume.GetGain();
|
|
} else if(addr == 0x4092) {
|
|
value &= 0xC0;
|
|
value |= _mod.GetGain();
|
|
}
|
|
|
|
return value;
|
|
}
|
|
|
|
void WriteRegister(uint16_t addr, uint8_t value)
|
|
{
|
|
if(addr <= 0x407F) {
|
|
if(_waveWriteEnabled) {
|
|
_waveTable[addr & 0x3F] = value & 0x3F;
|
|
}
|
|
} else {
|
|
switch(addr) {
|
|
case 0x4080:
|
|
case 0x4082:
|
|
_volume.WriteReg(addr, value);
|
|
break;
|
|
|
|
case 0x4083:
|
|
_disableEnvelopes = (value & 0x40) == 0x40;
|
|
_haltWaveform = (value & 0x80) == 0x80;
|
|
if(_disableEnvelopes) {
|
|
_volume.ResetTimer();
|
|
_mod.ResetTimer();
|
|
}
|
|
_volume.WriteReg(addr, value);
|
|
break;
|
|
|
|
case 0x4084:
|
|
case 0x4085:
|
|
case 0x4086:
|
|
case 0x4087:
|
|
_mod.WriteReg(addr, value);
|
|
break;
|
|
|
|
case 0x4088:
|
|
_mod.WriteModTable(value);
|
|
break;
|
|
|
|
case 0x4089:
|
|
_masterVolume = value & 0x03;
|
|
_waveWriteEnabled = (value & 0x80) == 0x80;
|
|
break;
|
|
|
|
case 0x408A:
|
|
_volume.SetMasterEnvelopeSpeed(value);
|
|
_mod.SetMasterEnvelopeSpeed(value);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}; |