93 lines
2.8 KiB
C++
93 lines
2.8 KiB
C++
#pragma once
|
|
|
|
#include <cstdint>
|
|
|
|
#include "ClockedChip.h"
|
|
#include "Bus.h"
|
|
#include "Register.h"
|
|
|
|
#include "EightBitCompilerDefinitions.h"
|
|
|
|
namespace EightBit {
|
|
class Processor : public ClockedChip {
|
|
public:
|
|
// http://graphics.stanford.edu/~seander/bithacks.html#FixedSignExtend
|
|
// b: number of bits representing the number in x
|
|
// x: sign extend this b-bit number to r
|
|
[[nodiscard]] static constexpr int8_t signExtend(int b, uint8_t x) noexcept {
|
|
const uint8_t m = bit(b - 1); // mask can be pre-computed if b is fixed
|
|
x = x & (bit(b) - 1); // (Skip this if bits in x above position b are already zero.)
|
|
const auto result = (x ^ m) - m;
|
|
return result;
|
|
}
|
|
|
|
Processor(const Processor& rhs) noexcept;
|
|
bool operator==(const Processor& rhs) const noexcept;
|
|
|
|
[[nodiscard]] constexpr auto& PC() noexcept { return m_pc; }
|
|
[[nodiscard]] constexpr const auto& PC() const noexcept { return m_pc; }
|
|
|
|
int run(int limit) noexcept;
|
|
virtual int step() noexcept = 0;
|
|
virtual void execute() noexcept = 0;
|
|
void execute(uint8_t value) noexcept;
|
|
|
|
[[nodiscard]] virtual register16_t peekWord(register16_t address) noexcept = 0;
|
|
virtual void pokeWord(register16_t address, register16_t value) noexcept = 0;
|
|
|
|
DECLARE_PIN_INPUT(RESET)
|
|
DECLARE_PIN_INPUT(INT)
|
|
|
|
protected:
|
|
Processor(Bus& memory) noexcept;
|
|
|
|
[[nodiscard]] constexpr auto& opcode() noexcept { return m_opcode; }
|
|
[[nodiscard]] constexpr auto& BUS() noexcept { return m_bus; }
|
|
|
|
virtual void handleRESET();
|
|
virtual void handleINT();
|
|
|
|
void memoryWrite(register16_t address, uint8_t data);
|
|
void memoryWrite(register16_t address);
|
|
void memoryWrite(uint8_t data);
|
|
virtual void memoryWrite();
|
|
virtual void busWrite();
|
|
|
|
uint8_t memoryRead(register16_t address);
|
|
virtual uint8_t memoryRead();
|
|
virtual uint8_t busRead();
|
|
|
|
uint8_t fetchByte();
|
|
|
|
[[nodiscard]] virtual register16_t getWord() = 0;
|
|
virtual void setWord(register16_t value) = 0;
|
|
|
|
[[nodiscard]] register16_t getWordPaged(register16_t address);
|
|
[[nodiscard]] register16_t getWordPaged(uint8_t page, uint8_t offset);
|
|
[[nodiscard]] virtual register16_t getWordPaged() = 0;
|
|
void setWordPaged(register16_t address, register16_t value);
|
|
void setWordPaged(uint8_t page, uint8_t offset, register16_t value);
|
|
virtual void setWordPaged(register16_t value) = 0;
|
|
|
|
[[nodiscard]] virtual register16_t fetchWord() = 0;
|
|
|
|
virtual void push(uint8_t value) = 0;
|
|
[[nodiscard]] virtual uint8_t pop() = 0;
|
|
|
|
virtual void pushWord(register16_t value) = 0;
|
|
[[nodiscard]] virtual register16_t popWord() = 0;
|
|
|
|
[[nodiscard]] register16_t getWord(register16_t address);
|
|
void setWord(register16_t address, register16_t value);
|
|
|
|
void jump(const register16_t destination) noexcept;
|
|
virtual void call(register16_t destination);
|
|
virtual void ret();
|
|
|
|
private:
|
|
Bus& m_bus;
|
|
uint8_t m_opcode = Mask8;
|
|
register16_t m_pc;
|
|
};
|
|
}
|