EightBit/src/IntelProcessor.cpp

114 lines
2.7 KiB
C++

#include "stdafx.h"
#include "../inc/IntelProcessor.h"
std::array<int, 8> EightBit::IntelProcessor::m_halfCarryTableAdd = { { 0, 0, 1, 0, 1, 0, 1, 1 } };
std::array<int, 8> EightBit::IntelProcessor::m_halfCarryTableSub = { { 0, 1, 1, 1, 0, 0, 0, 1 } };
EightBit::IntelProcessor::IntelProcessor(Bus& bus)
: LittleEndianProcessor(bus) {
for (int i = 0; i < 0x100; ++i)
m_decodedOpcodes.at(i) = i;
LoweredHALT.connect([this](EventArgs) noexcept { --PC(); });
RaisedHALT.connect([this](EventArgs) noexcept { ++PC(); });
RaisedPOWER.connect([this](EventArgs) {
PC() = SP() = Mask16;
resetWorkingRegisters();
raiseHALT();
});
}
EightBit::IntelProcessor::IntelProcessor(const IntelProcessor& rhs) noexcept
: LittleEndianProcessor(rhs) {
m_sp = rhs.m_sp;
m_memptr = rhs.m_memptr;
HALT() = rhs.HALT();
}
void EightBit::IntelProcessor::resetWorkingRegisters() noexcept {
AF() = BC() = DE() = HL() = Mask16;
}
DEFINE_PIN_LEVEL_CHANGERS(HALT, IntelProcessor);
void EightBit::IntelProcessor::handleRESET() {
Processor::handleRESET();
PC() = 0;
}
void EightBit::IntelProcessor::push(const uint8_t value) {
memoryWrite(--SP(), value);
}
uint8_t EightBit::IntelProcessor::pop() {
return memoryRead(SP()++);
}
EightBit::register16_t EightBit::IntelProcessor::getWord() {
const auto returned = LittleEndianProcessor::getWord();
MEMPTR() = BUS().ADDRESS();
return returned;
}
void EightBit::IntelProcessor::setWord(const register16_t value) {
LittleEndianProcessor::setWord(value);
MEMPTR() = BUS().ADDRESS();
}
void EightBit::IntelProcessor::restart(const uint8_t address) {
call(MEMPTR() = { address, 0 });
}
int EightBit::IntelProcessor::callConditional(const int condition) {
MEMPTR() = fetchWord();
if (condition)
call(MEMPTR());
return condition;
}
int EightBit::IntelProcessor::jumpConditional(const int condition) {
MEMPTR() = fetchWord();
if (condition)
jump(MEMPTR());
return condition;
}
int EightBit::IntelProcessor::returnConditional(const int condition) {
if (condition)
ret();
return condition;
}
void EightBit::IntelProcessor::jr(const int8_t offset) noexcept {
jump(MEMPTR() = PC() + offset);
}
int EightBit::IntelProcessor::jrConditional(const int condition) {
const auto offsetAddress = PC()++;
if (condition) {
const auto offset = memoryRead(offsetAddress);
jr(offset);
}
return condition;
}
void EightBit::IntelProcessor::ret() {
LittleEndianProcessor::ret();
MEMPTR() = PC();
}
bool EightBit::IntelProcessor::operator==(const EightBit::IntelProcessor& rhs) const noexcept {
return
LittleEndianProcessor::operator==(rhs)
&& HALT() == rhs.HALT()
&& MEMPTR() == rhs.MEMPTR()
&& SP() == rhs.SP()
&& AF() == rhs.AF()
&& BC() == rhs.BC()
&& DE() == rhs.DE()
&& HL() == rhs.HL();
}