mirror of
https://github.com/MoleskiCoder/EightBit.git
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1edabd79f3
Signed-off-by: Adrian Conlon <Adrian.conlon@gmail.com>
39 lines
747 B
C++
39 lines
747 B
C++
#include "stdafx.h"
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#include "Processor.h"
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EightBit::Processor::Processor(Bus& bus)
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: m_bus(bus) {
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}
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void EightBit::Processor::reset() {
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if (lowered(POWER()))
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throw std::logic_error("POWER cannot be low");
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raise(INT());
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raise(NMI());
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raise(RESET());
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PC().word = MEMPTR().word = 0;
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}
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int EightBit::Processor::run(int limit) {
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int current = 0;
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while (LIKELY(powered()) && current < limit) {
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current += singleStep();
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}
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return current;
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}
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int EightBit::Processor::singleStep() {
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if (UNLIKELY(lowered(RESET())))
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reset();
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return step();
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}
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uint8_t EightBit::Processor::fetchByte() {
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return getByte(PC().word++);
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}
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void EightBit::Processor::fetchWord(register16_t& output) {
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output.low = fetchByte();
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output.high = fetchByte();
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}
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