102 lines
2.0 KiB
C++
102 lines
2.0 KiB
C++
#pragma once
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#include <cstdint>
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#include <array>
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#include <functional>
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#include "Memory.h"
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#include "Signal.h"
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namespace EightBit {
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class Processor {
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public:
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enum Masks {
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Mask1 = 0x01,
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Mask2 = 0x03,
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Mask3 = 0x07,
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Mask4 = 0x0f,
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Mask5 = 0x1f,
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Mask6 = 0x3f,
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Mask7 = 0x7f,
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Mask8 = 0xff,
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};
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enum Bits {
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Bit16 = 0x10000,
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Bit15 = 0x8000,
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Bit14 = 0x4000,
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Bit13 = 0x2000,
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Bit12 = 0x1000,
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Bit11 = 0x800,
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Bit10 = 0x400,
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Bit9 = 0x200,
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Bit8 = 0x100,
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Bit7 = 0x80,
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Bit6 = 0x40,
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Bit5 = 0x20,
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Bit4 = 0x10,
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Bit3 = 0x8,
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Bit2 = 0x4,
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Bit1 = 0x2,
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Bit0 = 0x1,
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};
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static uint8_t highNibble(uint8_t value) { return value >> 4; }
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static uint8_t lowNibble(uint8_t value) { return value & Mask4; }
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static uint8_t promoteNibble(uint8_t value) { return value << 4; }
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static uint8_t demoteNibble(uint8_t value) { return highNibble(value); }
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static uint16_t makeWord(uint8_t low, uint8_t high) {
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return (high << 8) | low;
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}
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Processor(Memory& memory);
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const Memory& getMemory() const { return m_memory; }
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register16_t getProgramCounter() const { return pc; }
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void setProgramCounter(register16_t value) { pc = value; }
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register16_t getStackPointer() const { return sp; }
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void setStackPointer(register16_t value) { sp = value; }
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bool isHalted() const { return m_halted; }
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void halt() { --pc.word; m_halted = true; }
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virtual void initialise();
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void reset();
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virtual register16_t getWord(uint16_t address) const {
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return m_memory.getWord(address);
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}
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virtual void setWord(uint16_t address, register16_t value) {
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m_memory.setWord(address, value);
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}
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protected:
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Memory& m_memory;
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int cycles;
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register16_t pc;
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register16_t sp;
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bool m_halted;
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void pushWord(register16_t value);
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register16_t popWord();
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uint8_t fetchByte() {
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return m_memory.get(pc.word++);
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}
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uint16_t fetchWord() {
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auto value = getWord(pc.word);
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pc.word += 2;
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return value.word;
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}
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};
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} |