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Overclocking: Improved compatibility with games that write to $4011 + fixed PAL issues with OC

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This commit is contained in:
Souryo 2017-07-17 19:35:16 -04:00
parent a4d0b00fe7
commit 547fbab29f
6 changed files with 13 additions and 16 deletions
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9
Core/DeltaModulationChannel.cpp
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@ -33,6 +33,8 @@ void DeltaModulationChannel::Reset(bool softReset)
_silenceFlag = true;
_needToRun = false;
_lastValue4011 = 0;
//Not sure if this is accurate, but it seems to make things better rather than worse (for dpcmletterbox)
//"On the real thing, I think the power-on value is 428 (or the equivalent at least - it uses a linear feedback shift register), though only the even/oddness should matter for this test."
_period = (GetNesModel() == NesModel::NTSC ? _dmcPeriodLookupTableNtsc : _dmcPeriodLookupTablePal)[0] - 1;
@ -153,8 +155,9 @@ void DeltaModulationChannel::WriteRAM(uint16_t addr, uint8_t value)
break;
case 1: { //4011
uint8_t newValue = value & 0x7F;
uint8_t previousLevel = _outputLevel;
_outputLevel = value & 0x7F;
_outputLevel = newValue;
if(EmulationSettings::CheckFlag(EmulationFlags::ReduceDmcPopping) && abs(_outputLevel - previousLevel) > 50) {
//Reduce popping sounds for 4011 writes
@ -164,9 +167,11 @@ void DeltaModulationChannel::WriteRAM(uint16_t addr, uint8_t value)
//4011 applies new output right away, not on the timer's reload. This fixes bad DMC sound when playing through 4011.
AddOutput(_outputLevel);
if((value & 0x7F) > 0 && EmulationSettings::GetOverclockAdjustApu()) {
if(_lastValue4011 != value && newValue > 0) {
Console::SetNextFrameOverclockStatus(true);
}
_lastValue4011 = newValue;
break;
}

2
Core/DeltaModulationChannel.h
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@ -30,6 +30,8 @@ private:
bool _silenceFlag = true;
bool _needToRun = false;
uint8_t _lastValue4011 = 0;
void InitSample();
void FillReadBuffer();

1
Core/EmulationSettings.cpp
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@ -42,7 +42,6 @@ bool EmulationSettings::_hasOverclock = false;
uint32_t EmulationSettings::_overclockRate = 100;
uint32_t EmulationSettings::_extraScanlinesBeforeNmi = 0;
uint32_t EmulationSettings::_extraScanlinesAfterNmi = 0;
uint32_t EmulationSettings::_ppuScanlineCount = 262;
double EmulationSettings::_effectiveOverclockRate = 100;
bool EmulationSettings::_overclockAdjustApu = true;
bool EmulationSettings::_disableOverclocking = false;

7
Core/EmulationSettings.h
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@ -397,7 +397,6 @@ private:
static bool _disableOverclocking;
static uint32_t _extraScanlinesBeforeNmi;
static uint32_t _extraScanlinesAfterNmi;
static uint32_t _ppuScanlineCount;
static double _effectiveOverclockRate;
static double _effectiveOverclockRateSound;
@ -727,12 +726,6 @@ public:
_audioSettingsChanged = true;
}
static void SetPpuScanlineCount(uint32_t scanlineCount)
{
_ppuScanlineCount = scanlineCount;
UpdateEffectiveOverclockRate();
}
static void DisableOverclocking(bool disabled)
{
_disableOverclocking = disabled;

4
Core/PPU.cpp
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@ -112,25 +112,23 @@ void PPU::SetNesModel(NesModel model)
_vblankEnd = 260;
_standardNmiScanline = 241;
_standardVblankEnd = 260;
EmulationSettings::SetPpuScanlineCount(262);
break;
case NesModel::PAL:
_nmiScanline = 241;
_vblankEnd = 310;
_standardNmiScanline = 241;
_standardVblankEnd = 310;
EmulationSettings::SetPpuScanlineCount(312);
break;
case NesModel::Dendy:
_nmiScanline = 291;
_vblankEnd = 310;
_standardNmiScanline = 291;
_standardVblankEnd = 310;
EmulationSettings::SetPpuScanlineCount(312);
break;
}
_nmiScanline += EmulationSettings::GetPpuExtraScanlinesBeforeNmi();
_palSpriteEvalScanline = _nmiScanline + 24;
_standardVblankEnd += EmulationSettings::GetPpuExtraScanlinesBeforeNmi();
_vblankEnd += EmulationSettings::GetPpuExtraScanlinesAfterNmi() + EmulationSettings::GetPpuExtraScanlinesBeforeNmi();
}

2
Core/PPU.h
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@ -28,7 +28,6 @@ class PPU : public IMemoryHandler, public Snapshotable
{
protected:
static PPU* Instance;
static constexpr uint16_t _palSpriteEvalScanline = 265;
BaseMapper *_mapper;
@ -52,6 +51,7 @@ class PPU : public IMemoryHandler, public Snapshotable
uint16_t _standardNmiScanline;
uint16_t _vblankEnd;
uint16_t _nmiScanline;
uint16_t _palSpriteEvalScanline;
PPUControlFlags _flags;
PPUStatusFlags _statusFlags;