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Run APU every 1 CPU clock

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This commit is contained in:
Souryo 2015-07-16 16:55:16 -04:00
parent 444db81dfc
commit d70010f324
5 changed files with 34 additions and 37 deletions
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53
Core/APU.cpp
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@ -109,21 +109,17 @@ void APU::Run()
//-At the end of a frame
//-Before APU registers are read/written to
//-When a DMC or FrameCounter interrupt needs to be fired
uint32_t targetCycle = CPU::GetCycleCount();
uint32_t currentCycle = _previousCycle;
uint32_t cyclesToRun = targetCycle - _previousCycle;
uint32_t cyclesToRun = _currentCycle - _previousCycle;
while(currentCycle < targetCycle) {
currentCycle += _frameCounter->Run(cyclesToRun);
while(_previousCycle < _currentCycle) {
_previousCycle += _frameCounter->Run(cyclesToRun);
_squareChannel[0]->Run(currentCycle);
_squareChannel[1]->Run(currentCycle);
_noiseChannel->Run(currentCycle);
_triangleChannel->Run(currentCycle);
_deltaModulationChannel->Run(currentCycle);
_squareChannel[0]->Run(_previousCycle);
_squareChannel[1]->Run(_previousCycle);
_noiseChannel->Run(_previousCycle);
_triangleChannel->Run(_previousCycle);
_deltaModulationChannel->Run(_previousCycle);
}
_previousCycle = targetCycle;
}
void APU::StaticRun()
@ -142,21 +138,16 @@ bool APU::IrqPending(uint32_t currentCycle)
return false;
}
void APU::ExecStatic(uint32_t currentCpuCycle)
void APU::ExecStatic()
{
Instance->Exec(currentCpuCycle);
Instance->Exec();
}
bool APU::Exec(uint32_t currentCpuCycle)
void APU::Exec()
{
if(IrqPending(currentCpuCycle)) {
_currentCycle++;
if(_currentCycle == 20000) {
Run();
}
if(currentCpuCycle >= 29780) {
Run();
_previousCycle = 0;
_squareChannel[0]->EndFrame();
_squareChannel[1]->EndFrame();
@ -164,19 +155,19 @@ bool APU::Exec(uint32_t currentCpuCycle)
_noiseChannel->EndFrame();
_deltaModulationChannel->EndFrame();
_blipBuffer->end_frame(currentCpuCycle);
_blipBuffer->end_frame(_currentCycle);
// Read some samples out of Blip_Buffer if there are enough to fill our output buffer
uint32_t availableSampleCount = _blipBuffer->samples_avail();
if(availableSampleCount >= APU::SamplesPerFrame) {
size_t sampleCount = _blipBuffer->read_samples(_outputBuffer, APU::SamplesPerFrame);
if(APU::AudioDevice) {
APU::AudioDevice->PlayBuffer(_outputBuffer, (uint32_t)(sampleCount * BitsPerSample / 8));
}
size_t sampleCount = _blipBuffer->read_samples(_outputBuffer, APU::SamplesPerFrame);
if(APU::AudioDevice) {
APU::AudioDevice->PlayBuffer(_outputBuffer, (uint32_t)(sampleCount * BitsPerSample / 8));
}
return true;
_currentCycle = 0;
_previousCycle = 0;
} else if(IrqPending(_currentCycle)) {
Run();
}
return false;
}
void APU::StopAudio()
@ -189,6 +180,7 @@ void APU::StopAudio()
void APU::Reset()
{
_currentCycle = 0;
_previousCycle = 0;
_squareChannel[0]->Reset();
_squareChannel[1]->Reset();
@ -200,6 +192,7 @@ void APU::Reset()
void APU::StreamState(bool saving)
{
Stream<uint32_t>(_currentCycle);
Stream<uint32_t>(_previousCycle);
Stream(_squareChannel[0].get());
Stream(_squareChannel[1].get());

5
Core/APU.h
View File

@ -21,6 +21,7 @@ class APU : public Snapshotable, public IMemoryHandler
static APU* Instance;
uint32_t _previousCycle = 0;
uint32_t _currentCycle = 0;
vector<unique_ptr<SquareChannel>> _squareChannel;
unique_ptr<TriangleChannel> _triangleChannel;
@ -62,8 +63,8 @@ class APU : public Snapshotable, public IMemoryHandler
void WriteRAM(uint16_t addr, uint8_t value);
void GetMemoryRanges(MemoryRanges &ranges);
bool Exec(uint32_t currentCpuCycle);
static void ExecStatic(uint32_t currentCpuCycle);
void Exec();
static void ExecStatic();
static void StaticRun();
static void StopAudio();

2
Core/CPU.cpp
View File

@ -1,6 +1,7 @@
#include "stdafx.h"
#include "CPU.h"
#include "PPU.h"
#include "APU.h"
CPU* CPU::Instance = nullptr;
@ -121,6 +122,7 @@ void CPU::EndFrame()
void CPU::IncCycleCount()
{
PPU::ExecStatic();
APU::ExecStatic();
_cycleCount++;
}

1
Core/CPU.h
View File

@ -662,7 +662,6 @@ public:
static const uint32_t ClockRate = 1789773;
CPU(MemoryManager *memoryManager);
static int32_t GetCycleCount() { return CPU::Instance->_cycleCount; }
static int32_t GetRelativeCycleCount() { return CPU::Instance->_relativeCycleCount + CPU::Instance->_cycleCount; }
static void SetNMIFlag() { CPU::Instance->_state.NMIFlag = true; }
static void ClearNMIFlag() { CPU::Instance->_state.NMIFlag = false; }

10
Core/Console.cpp
View File

@ -169,13 +169,15 @@ void Console::Run()
_runLock.Acquire();
_stopLock.Acquire();
uint32_t lastFrameNumber = -1;
while(true) {
bool frameDone = _apu->Exec(_cpu->Exec());
if(frameDone) {
_cpu->Exec();
uint32_t currentFrameNumber = PPU::GetFrameCount();
if(currentFrameNumber != lastFrameNumber) {
lastFrameNumber = currentFrameNumber;
_cpu->EndFrame();
if(CheckFlag(EmulationFlags::LimitFPS) && frameDone) {
if(CheckFlag(EmulationFlags::LimitFPS)) {
elapsedTime = clockTimer.GetElapsedMS();
while(targetTime > elapsedTime) {
if(targetTime - elapsedTime > 2) {