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CPU: Implement TRB/TSB instructions

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This commit is contained in:
Sour 2019-02-14 07:08:46 -05:00
parent 3cf0b0e46d
commit f979d31971
2 changed files with 31 additions and 7 deletions
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36
Core/Cpu.Instructions.cpp
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@ -799,9 +799,9 @@ void Cpu::STZ()
/******************* /*******************
Bit test operations Bit test operations
********************/ ********************/
template<typename T> void Cpu::TestBits(T value) template<typename T> void Cpu::TestBits(T value, bool alterZeroFlagOnly)
{ {
if(_instAddrMode <= AddrMode::ImmM) { if(alterZeroFlagOnly) {
//"Immediate addressing only affects the z flag (with the result of the bitwise And), but does not affect the n and v flags." //"Immediate addressing only affects the z flag (with the result of the bitwise And), but does not affect the n and v flags."
if(((T)_state.A & value) == 0) { if(((T)_state.A & value) == 0) {
SetFlags(ProcFlags::Zero); SetFlags(ProcFlags::Zero);
@ -827,20 +827,44 @@ template<typename T> void Cpu::TestBits(T value)
void Cpu::BIT() void Cpu::BIT()
{ {
if(CheckFlag(ProcFlags::MemoryMode8)) { if(CheckFlag(ProcFlags::MemoryMode8)) {
TestBits<uint8_t>(GetByteValue()); TestBits<uint8_t>(GetByteValue(), _instAddrMode <= AddrMode::ImmM);
} else { } else {
TestBits<uint16_t>(GetWordValue()); TestBits<uint16_t>(GetWordValue(), _instAddrMode <= AddrMode::ImmM);
} }
} }
void Cpu::TRB() void Cpu::TRB()
{ {
//TODO if(CheckFlag(ProcFlags::MemoryMode8)) {
TestBits<uint8_t>(GetByteValue(), true);
uint8_t value = ReadData(_operand);
value &= ~_state.A;
Write(_operand, value);
} else {
TestBits<uint16_t>(GetWordValue(), true);
uint16_t value = ReadDataWord(_operand);
value &= ~_state.A;
WriteWord(_operand, value);
}
} }
void Cpu::TSB() void Cpu::TSB()
{ {
//TODO if(CheckFlag(ProcFlags::MemoryMode8)) {
TestBits<uint8_t>(GetByteValue(), true);
uint8_t value = ReadData(_operand);
value |= _state.A;
Write(_operand, value);
} else {
TestBits<uint16_t>(GetWordValue(), true);
uint16_t value = ReadDataWord(_operand);
value |= _state.A;
WriteWord(_operand, value);
}
} }
/****************** /******************

2
Core/Cpu.h
View file

@ -205,7 +205,7 @@ private:
void STZ(); void STZ();
//Test bits //Test bits
template<typename T> void TestBits(T value); template<typename T> void TestBits(T value, bool alterZeroFlagOnly);
void BIT(); void BIT();
void TRB(); void TRB();