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Add JML, AND AbsoluteLong, ADC AbsoluteLong

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scawful
2023-08-19 19:12:28 -04:00
parent f5c5c34b47
commit 7dcbc7f83c
4 changed files with 350 additions and 176 deletions
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29
src/app/emu/cpu.cc
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@@ -66,6 +66,9 @@ uint8_t CPU::FetchByteDirectPage(uint8_t operand) {
}
void CPU::ExecuteInstruction(uint8_t opcode) {
// Update the PC based on the Program Bank Register
PC |= (static_cast<uint16_t>(PB) << 16);
// uint8_t opcode = FetchByte();
uint8_t operand = -1;
switch (opcode) {
@@ -94,7 +97,7 @@ void CPU::ExecuteInstruction(uint8_t opcode) {
ADC(operand);
break;
case 0x6F: // ADC Absolute Long
operand = memory.ReadByte(AbsoluteLong());
operand = memory.ReadWord(AbsoluteLong());
ADC(operand);
break;
case 0x71: // ADC DP Indirect Indexed, Y
@@ -153,8 +156,7 @@ void CPU::ExecuteInstruction(uint8_t opcode) {
AND(Absolute());
break;
case 0x2F: // AND Absolute Long
operand = memory.ReadByte(AbsoluteLong());
AND(operand);
ANDAbsoluteLong(AbsoluteLong());
break;
case 0x31: // AND DP Indirect Indexed, Y
operand = memory.ReadByte(DirectPageIndirectIndexedY());
@@ -177,16 +179,13 @@ void CPU::ExecuteInstruction(uint8_t opcode) {
AND(operand);
break;
case 0x39: // AND Absolute Indexed, Y
operand = memory.ReadByte(AbsoluteIndexedY());
AND(operand);
AND(AbsoluteIndexedY());
break;
case 0x3D: // AND Absolute Indexed, X
operand = memory.ReadByte(AbsoluteIndexedX());
AND(operand);
AND(AbsoluteIndexedX());
break;
case 0x3F: // AND Absolute Long Indexed, X
operand = memory.ReadByte(AbsoluteLongIndexedX());
AND(operand);
AND(AbsoluteLongIndexedX());
break;
case 0x06: // ASL Direct Page
@@ -451,7 +450,7 @@ void CPU::ExecuteInstruction(uint8_t opcode) {
JMP(Absolute());
break;
case 0x5C: // JMP Absolute Long
// JMP();
JML(AbsoluteLong());
break;
case 0x6C: // JMP Absolute Indirect
JMP(AbsoluteIndirect());
@@ -574,7 +573,7 @@ void CPU::ExecuteInstruction(uint8_t opcode) {
break;
case 0xEA: // NOP No Operation
// NOP();
NOP();
break;
case 0x01: // ORA DP Indexed Indirect, X
@@ -1010,6 +1009,14 @@ void CPU::AND(uint16_t address) {
}
}
// New function for absolute long addressing mode
void CPU::ANDAbsoluteLong(uint32_t address) {
uint32_t operand32 = memory.ReadWordLong(address);
A &= operand32;
SetZeroFlag(A == 0);
SetNegativeFlag(A & 0x80000000);
}
} // namespace emu
} // namespace app
} // namespace yaze