Added basic EPSM IRQ behavior

Core/BaseMapper.cpp

@@ -14,7 +14,7 @@
 #include "CPU.h"
 
 void BaseMapper::WriteRegister(uint16_t addr, uint8_t value) { }
-void BaseMapper::WriteEPSM(uint16_t addr, uint8_t value) { _epsmaudio->WriteRegister(addr, value); }
+void BaseMapper::WriteEPSM(uint16_t addr, uint8_t value) {_epsmaudio->WriteRegister(addr, value); }
 uint8_t BaseMapper::ReadRegister(uint16_t addr) { return 0; }
 void BaseMapper::InitMapper(RomData &romData) { }
 void BaseMapper::Reset(bool softReset) { }
@@ -787,7 +787,7 @@ uint8_t BaseMapper::DebugReadRAM(uint16_t addr)
 void BaseMapper::WriteRAM(uint16_t addr, uint8_t value)
 {
 	if((addr == 0x4016) & (_console->GetCpu()->GetCycleCount() % 2 == 1)){ WriteEPSM(addr, value); }
-	if ((addr >= 0x401c && addr <= 0x401f)) { WriteEPSM(addr, value); }
+	if ((addr >= 0x401c && addr <= 0x401f)) {WriteEPSM(addr, value); }
 	if(_isWriteRegisterAddr[addr]) {
 		if(_hasBusConflicts) {
 			uint8_t prgValue = _prgPages[addr >> 8][(uint8_t)addr];

Core/EPSMAudio.h

@@ -5,6 +5,7 @@
 #include "BaseExpansionAudio.h"
 #include "SSGAudio.h"
 #include "Console.h"
+#include "Cpu.h"
 
 #include <array>
 #include "ym3438.h"
@@ -19,9 +20,22 @@ class EPSMAudio : public EPSMSSGAudio
 	int16_t _lastOutputs[2];
 	int16_t _currentOutputs[2];
 	uint8_t writeValue;
-	int16_t writeAddr;
+	uint16_t writeAddr;
+	uint16_t irqATimer;
+	uint16_t irqBTimer;
+	uint16_t irqACurrentTimer;
+	uint16_t irqBCurrentTimer;
+	uint8_t irqATimerEnable;
+	uint8_t irqBTimerEnable;
+	uint8_t irqAHighValue;
+	uint8_t irqALowValue;
+	uint8_t irqBValue;
+	uint16_t currentRegister;
+
 
 	double _clock;
+	double _clockIRQ;
+	double _cycleCountIRQ = 0;
 
 	static constexpr uint8_t cycleCount = 24;
 
@@ -39,7 +53,6 @@ class EPSMAudio : public EPSMSSGAudio
 
 	void UpdateOutputLevel()
 	{
-		int16_t summedOutput = 0;
 		for (size_t x = 0; x < 2; x++)
 		{
 			_console->GetApu()->AddExpansionAudioDelta(x == 0 ? AudioChannel::EPSM_L : AudioChannel::EPSM_R, _currentOutputs[x] - _lastOutputs[x]);
@@ -69,6 +82,71 @@ class EPSMAudio : public EPSMSSGAudio
 		};
 	}
 
+
+	void WriteToChipIRQ(uint16_t addr, uint8_t value)
+	{
+		switch (addr) {
+		case 0xC000:
+		case 0xC002:
+			currentRegister = value;
+			break;
+
+		case 0xE000:
+			if (currentRegister == 0x24) {
+				//Timer A High 8 bits
+				//std::cout << "Timer A High 8 bits" << std::endl;
+				irqAHighValue = value;
+			}
+			if (currentRegister == 0x25) {
+				//Timer A Low 2 bits
+				//std::cout << "Timer A Low 2 bits" << std::endl;
+				irqALowValue = (value & 0x3);
+			}
+			if (currentRegister == 0x26) {
+				//Timer B 8 bits
+				//std::cout << "Timer B 8 bits" << std::endl;
+				irqBValue = value;
+			}
+			if ((currentRegister == 0x27) && ((value & 0x5)|(value & 0xA))) {
+				//Load+Enable IRQ (0xA = TimerB, 0x5 = TimerA)
+				//std::cout << "Load+Enable IRQ" << std::endl;
+				if ((currentRegister == 0x27) && (value & 0x5)) {
+					irqATimer = (uint16_t(irqAHighValue) << 2) | irqALowValue;
+					irqACurrentTimer = 72 * (1024 - irqATimer) * 2;
+					irqATimerEnable = 1;
+					//std::cout << "Load+Enable IRQ A" << std::endl;
+				}
+				if ((currentRegister == 0x27) && (value & 0xA)) {
+					irqBTimer = 1152 * (256 - irqBValue) * 2;
+					irqBCurrentTimer = irqBTimer;
+					irqBTimerEnable = 1;
+					//std::cout << "Load+Enable IRQ B " << irqBCurrentTimer << std::endl;
+				}
+			}
+			if ((currentRegister == 0x27) && (value & 0x30)) {
+				//Enable/Reset IRQ
+				//std::cout << std::hex << uint16_t(value) << "Reset IRQ" << std::endl;
+				_console->GetCpu()->ClearIrqSource(IRQSource::EPSM);
+				irqATimerEnable = 0;
+				irqBTimerEnable = 0;
+			}
+			if ((currentRegister == 0x29) && (value & 0x3)) {
+				//enable IRQ's
+				//std::cout << "enable IRQ's" << std::endl;
+			}
+			break;
+		case 0xE002:
+			/*if (currentRegister == 0x10) {
+				std::cout << "0x10" << std::endl;
+			}*/
+			break;
+		}
+
+		//irqBValue = value;
+		//std::cout << std::hex << irqBValue << std::endl;
+
+	}
+
 	uint32_t getClockFrequency()
 	{
 		return _console->GetSettings()->GetEPSMClockFrequency() / 6;
@@ -92,6 +170,29 @@ class EPSMAudio : public EPSMSSGAudio
 		EPSMSSGAudio::ClockAudio();
 
 		_clock += getClockFrequency() / (double)_console->GetCpu()->GetClockRate(_console->GetModel());
+		_clockIRQ += (getClockFrequency()*6) / (double)_console->GetCpu()->GetClockRate(_console->GetModel());
+		while (_clockIRQ >= _cycleCountIRQ) {
+			_cycleCountIRQ++;
+			//std::cout << _cycleCountIRQ << std::endl;
+			if (irqATimerEnable) {
+				irqACurrentTimer--;
+				if (!irqACurrentTimer) {
+					//std::cout << "***IRQ***" << std::endl;
+					irqATimerEnable = 0;
+					_console->GetCpu()->SetIrqSource(IRQSource::EPSM);
+				}
+
+			}
+			if (irqBTimerEnable) {
+				irqBCurrentTimer--;
+				if (!irqBCurrentTimer) {
+					//std::cout << "***IRQ***" << std::endl;
+					irqBTimerEnable = 0;
+					_console->GetCpu()->SetIrqSource(IRQSource::EPSM);
+				}
+
+			}
+		}
 
 		while (_clock >= cycleCount)
 		{
@@ -117,7 +218,6 @@ class EPSMAudio : public EPSMSSGAudio
 				if(input.wrote)
 				{
 					input.wrote = false;
-
 					OPN2_Write(&_chip, input.addr, input.data);
 				}
 			}
@@ -131,9 +231,9 @@ class EPSMAudio : public EPSMSSGAudio
 		}
 	}
 
-	virtual uint32_t GetSSGClockFrequency()
+	virtual uint32_t GetSSGClockFrequency() override
 	{
-		return EPSMSSGAudio::GetSSGClockFrequency() * (_console->GetSettings()->GetEPSMClockFrequency() / 3579545.0 );
+		return EPSMSSGAudio::GetSSGClockFrequency() * (_console->GetSettings()->GetEPSMClockFrequency() / 3579545 );
 	}
 
 public:
@@ -144,7 +244,10 @@ class EPSMAudio : public EPSMSSGAudio
 		_inputBuffer = {};
 
 		_clock = 0;
+		_clockIRQ = 0;
 
+		irqATimerEnable = 0;
+		irqBTimerEnable = 0;
 		OPN2_Reset(&_chip);
 		OPN2_SetChipType(0);
 	}
@@ -182,13 +285,13 @@ class EPSMAudio : public EPSMSSGAudio
 		if (addr == 0x401d) { addr = 0xE000; }
 		if (addr == 0x401e) { addr = 0xC002; }
 		if (addr == 0x401f) { addr = 0xE002; }
-
 		switch(addr) {
 			case 0xC000:
 			case 0xE000:
 			case 0xC002:
 			case 0xE002:
 
+				WriteToChipIRQ(addr, value);
 				const uint8_t a0 = (addr & 0xF000) == 0xE000;
 				const uint8_t a1 = !!(addr & 0xF);
 				EPSMSSGAudio::WriteRegister(addr, value);

Core/MemoryManager.cpp

@@ -133,7 +133,7 @@ void MemoryManager::Write(uint16_t addr, uint8_t value, MemoryOperationType oper
 {
 	if(_console->DebugProcessRamOperation(operationType, addr, value)) {
 		_ramWriteHandlers[addr]->WriteRAM(addr, value);
-		if ((addr == 0x4016) | (addr >= 0x401c && addr <= 0x401f)) {
+		if ((addr == 0x4016) /*| (addr >= 0x401c && addr <= 0x401f)*/) {
 			_ramWriteHandlers[0xE000]->WriteRAM(addr, value);
 		}
 	}

Core/Types.h

@@ -30,6 +30,7 @@ enum class IRQSource
 	FrameCounter = 2,
 	DMC = 4,
 	FdsDisk = 8,
+	EPSM = 16,
 };
 
 enum class MemoryOperation

Core/Vrc7Audio.h

@@ -41,7 +41,6 @@ class Vrc7Audio : public BaseExpansionAudio
 
 	void UpdateOutputLevel()
 	{
-		int16_t summedOutput = 0;
 		_console->GetApu()->AddExpansionAudioDelta(AudioChannel::VRC7, _currentOutput - _lastOutput);
 		_lastOutput = _currentOutput;
 	}