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CPU: Allow move instructions to be interrupted by an IRQ/NMI

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+ Implemented WAI instruction
This commit is contained in:
Sour 2019-03-02 10:58:25 -05:00
parent 28a151e00d
commit e321b247ac
1 changed files with 32 additions and 34 deletions
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30
Core/Cpu.Instructions.cpp
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@ -655,11 +655,10 @@ Move operations
****************/
void Cpu::MVN()
{
#ifndef DUMMYCPU
_state.DBR = _operand & 0xFF;
uint32_t destBank = _state.DBR << 16;
uint32_t srcBank = (_operand << 8) & 0xFF0000;
do {
uint8_t value = ReadData(srcBank | _state.X);
Write(destBank | _state.Y, value);
@ -670,23 +669,19 @@ void Cpu::MVN()
_state.Y++;
_state.A--;
if(_state.A != 0xFFFF) {
//"Idle" cycles, instruction re-reads OP code and operands before every new byte
Read((_state.K << 16) | (_state.PC - 3), MemoryOperationType::Read);
Read((_state.K << 16) | (_state.PC - 2), MemoryOperationType::Read);
Read((_state.K << 16) | (_state.PC - 1), MemoryOperationType::Read);
//Operation isn't done, set the PC back to the start of the instruction
_state.PC -= 3;
}
} while(_state.A != 0xFFFF);
#endif
}
void Cpu::MVP()
{
#ifndef DUMMYCPU
_state.DBR = _operand & 0xFF;
uint32_t destBank = _state.DBR << 16;
uint32_t srcBank = (_operand << 8) & 0xFF0000;
do {
uint8_t value = ReadData(srcBank | _state.X);
Write(destBank | _state.Y, value);
@ -698,13 +693,9 @@ void Cpu::MVP()
_state.A--;
if(_state.A != 0xFFFF) {
//"Idle" cycles, instruction re-reads OP code and operands before every new byte
Read((_state.K << 16) | (_state.PC - 3), MemoryOperationType::Read);
Read((_state.K << 16) | (_state.PC - 2), MemoryOperationType::Read);
Read((_state.K << 16) | (_state.PC - 1), MemoryOperationType::Read);
//Operation isn't done, set the PC back to the start of the instruction
_state.PC -= 3;
}
} while(_state.A != 0xFFFF);
#endif
}
/********************
@ -1090,7 +1081,14 @@ void Cpu::STP()
void Cpu::WAI()
{
#ifndef DUMMYCPU
//Wait for interrupt
while(!_irqSource && !_nmiFlag) {
_memoryManager->IncrementMasterClockValue<4>();
}
Idle();
Idle();
#endif
}
/****************