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Overhaul Cpu, interrupts, cycling, addressing, instructions, etc

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scawful
2024-04-22 16:59:04 -04:00
parent 1a4563f9e7
commit fd64835d22
4 changed files with 469 additions and 392 deletions
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34
src/app/emu/cpu/internal/addressing.cc
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@@ -12,30 +12,31 @@ uint32_t Cpu::Absolute(Cpu::AccessType access_type) {
}
uint32_t Cpu::AbsoluteIndexedX() {
uint16_t address = memory.ReadWord((PB << 16) | (PC + 1));
uint16_t address = ReadWord((PB << 16) | (PC + 1));
uint32_t effective_address = (DB << 16) | ((address + X) & 0xFFFF);
return effective_address;
}
uint32_t Cpu::AbsoluteIndexedY() {
uint16_t address = memory.ReadWord((PB << 16) | (PC + 1));
uint16_t address = ReadWord((PB << 16) | (PC + 1));
uint32_t effective_address = (DB << 16) | address + Y;
return effective_address;
}
uint16_t Cpu::AbsoluteIndexedIndirect() {
uint16_t address = FetchWord() + X;
return memory.ReadWord((DB << 16) | address & 0xFFFF);
callbacks_.idle(false);
return ReadWord((DB << 16) | address & 0xFFFF);
}
uint16_t Cpu::AbsoluteIndirect() {
uint16_t address = FetchWord();
return memory.ReadWord((PB << 16) | address);
return ReadWord((PB << 16) | address);
}
uint32_t Cpu::AbsoluteIndirectLong() {
uint16_t address = FetchWord();
return memory.ReadWordLong((PB << 16) | address);
return ReadWordLong((PB << 16) | address);
}
uint32_t Cpu::AbsoluteLong() { return FetchLong(); }
@@ -44,7 +45,7 @@ uint32_t Cpu::AbsoluteLongIndexedX() { return FetchLong() + X; }
void Cpu::BlockMove(uint16_t source, uint16_t dest, uint16_t length) {
for (int i = 0; i < length; i++) {
memory.WriteByte(dest + i, memory.ReadByte(source + i));
WriteByte(dest + i, ReadByte(source + i));
}
}
@@ -66,44 +67,47 @@ uint16_t Cpu::DirectPageIndexedY() {
uint16_t Cpu::DirectPageIndexedIndirectX() {
uint8_t operand = FetchByte();
if (D & 0xFF) {
callbacks_.idle(false); // dpr not 0: 1 extra cycle
}
callbacks_.idle(false);
uint16_t indirect_address = D + operand + X;
uint16_t effective_address = memory.ReadWord(indirect_address & 0xFFFF);
uint16_t effective_address = ReadWord(indirect_address & 0xFFFF);
return effective_address;
}
uint16_t Cpu::DirectPageIndirect() {
uint8_t dp = FetchByte();
uint16_t effective_address = D + dp;
return memory.ReadWord(effective_address);
return ReadWord(effective_address);
}
uint32_t Cpu::DirectPageIndirectLong() {
uint8_t dp = FetchByte();
uint16_t effective_address = D + dp;
return memory.ReadWordLong((0x00 << 0x10) | effective_address);
return ReadWordLong((0x00 << 0x10) | effective_address);
}
uint16_t Cpu::DirectPageIndirectIndexedY() {
uint8_t operand = FetchByte();
uint16_t indirect_address = D + operand;
return memory.ReadWord(indirect_address) + Y;
return ReadWord(indirect_address) + Y;
}
uint32_t Cpu::DirectPageIndirectLongIndexedY() {
uint8_t operand = FetchByte();
uint16_t indirect_address = D + operand;
uint16_t y_by_mode = GetAccumulatorSize() ? Y : Y & 0xFF;
uint32_t effective_address =
memory.ReadWordLong(indirect_address) + y_by_mode;
uint32_t effective_address = ReadWordLong(indirect_address) + y_by_mode;
return effective_address;
}
uint16_t Cpu::Immediate(bool index_size) {
bool bit_mode = index_size ? GetIndexSize() : GetAccumulatorSize();
if (bit_mode) {
return memory.ReadByte((PB << 16) | PC + 1);
return ReadByte((PB << 16) | PC + 1);
} else {
return memory.ReadWord((PB << 16) | PC + 1);
return ReadWord((PB << 16) | PC + 1);
}
}
@@ -115,7 +119,7 @@ uint16_t Cpu::StackRelative() {
uint32_t Cpu::StackRelativeIndirectIndexedY() {
uint8_t sr = FetchByte();
return (DB << 0x10) | (memory.ReadWord(SP() + sr) + Y);
return (DB << 0x10) | (ReadWord(SP() + sr) + Y);
}
} // namespace emu