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APU: Fixed Square 1 sweep bug (fixes Little Red Hood without breaking Super Dodge Ball). Fixed noise channel period (was set to twice the real value)

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This commit is contained in:
Souryo 2016-01-12 17:16:01 -05:00
parent 6aed632123
commit 070f07082e
5 changed files with 10 additions and 11 deletions
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10
Core/BaseApuChannel.h
View File

@ -21,7 +21,7 @@ private:
protected:
uint16_t _timer = 0;
uint16_t _period = 0;
uint32_t _clockDivider = 2; //All channels except triangle clock overy other cpu clock
uint16_t _periodMultiplier = 1;
void SetVolume(double volume)
{
@ -89,13 +89,13 @@ public:
while(_previousCycle < targetCycle) {
if(_timer == 0) {
Clock();
_timer = _period;
_previousCycle += _clockDivider;
_timer = _period * _periodMultiplier;
_previousCycle++;
} else {
uint32_t cyclesToRun = (targetCycle - _previousCycle) / _clockDivider;
uint32_t cyclesToRun = targetCycle - _previousCycle;
uint16_t skipCount = _timer > cyclesToRun ? cyclesToRun : _timer;
_timer -= skipCount;
_previousCycle += skipCount * _clockDivider;
_previousCycle += skipCount;
if(cyclesToRun == 0) {
break;

1
Core/DeltaModulationChannel.cpp
View File

@ -9,7 +9,6 @@ DeltaModulationChannel::DeltaModulationChannel(AudioChannel channel, Blip_Buffer
{
Instance = this;
_memoryManager = memoryManager;
_clockDivider = 1;
SetVolume(0.42545);
}

2
Core/NoiseChannel.h
View File

@ -73,7 +73,7 @@ public:
break;
case 2: //400E
_period = (GetNesModel() == NesModel::NTSC ? _noisePeriodLookupTableNtsc : _noisePeriodLookupTablePal)[value & 0x0F];
_period = (GetNesModel() == NesModel::NTSC ? _noisePeriodLookupTableNtsc : _noisePeriodLookupTablePal)[value & 0x0F] - 1;
_modeFlag = (value & 0x80) == 0x80;
break;

7
Core/SquareChannel.h
View File

@ -31,7 +31,7 @@ private:
bool IsMuted()
{
//A period of t < 8, either set explicitly or via a sweep period update, silences the corresponding pulse channel.
return _period < 8 || _sweepTargetPeriod > 0x7FF;
return _period < 8 || (!_sweepNegate && _sweepTargetPeriod > 0x7FF);
}
void InitializeSweep(uint8_t regValue)
@ -54,7 +54,7 @@ private:
_sweepTargetPeriod = _period - shiftResult;
if(_isChannel1) {
// As a result, a negative sweep on pulse channel 1 will subtract the shifted period value minus 1
_sweepTargetPeriod++;
_sweepTargetPeriod--;
}
} else {
_sweepTargetPeriod = _period + shiftResult;
@ -81,6 +81,7 @@ public:
{
SetVolume(0.1128);
_isChannel1 = isChannel1;
_periodMultiplier = 2;
}
virtual void Reset(bool softReset)
@ -150,7 +151,7 @@ public:
_period |= (value & 0x07) << 8;
//The sequencer is restarted at the first value of the current sequence.
_timer = _period + 1;
_timer = _period * 2;
_dutyPos = 0;
//The envelope is also restarted.

1
Core/TriangleChannel.h
View File

@ -31,7 +31,6 @@ protected:
public:
TriangleChannel(AudioChannel channel, Blip_Buffer* buffer) : ApuLengthCounter(channel, buffer)
{
_clockDivider = 1; //Triangle clocks at the same speed as the cpu
SetVolume(0.12765);
}