78 lines
1.6 KiB
C++
78 lines
1.6 KiB
C++
#pragma once
|
|
|
|
#include <array>
|
|
#include <cstdint>
|
|
#include <string>
|
|
|
|
namespace EightBit {
|
|
|
|
typedef union {
|
|
struct {
|
|
#ifdef HOST_LITTLE_ENDIAN
|
|
uint8_t low;
|
|
uint8_t high;
|
|
#endif
|
|
#ifdef HOST_BIG_ENDIAN
|
|
uint8_t high;
|
|
uint8_t low;
|
|
#endif
|
|
};
|
|
uint16_t word;
|
|
} register16_t;
|
|
|
|
class Memory {
|
|
public:
|
|
Memory(uint16_t addressMask);
|
|
|
|
virtual uint16_t& ADDRESS() { return m_address; }
|
|
virtual uint8_t& DATA() { return *m_data; }
|
|
|
|
virtual uint8_t& placeDATA(uint8_t value) {
|
|
m_temporary = value;
|
|
m_data = &m_temporary;
|
|
return DATA();
|
|
}
|
|
|
|
virtual uint8_t& referenceDATA(uint8_t& value) {
|
|
m_data = &value;
|
|
return DATA();
|
|
}
|
|
|
|
virtual uint8_t peek(uint16_t address) const;
|
|
virtual uint16_t peekWord(uint16_t address) const;
|
|
|
|
virtual uint8_t get(uint16_t address) {
|
|
ADDRESS() = address;
|
|
return reference();
|
|
}
|
|
|
|
virtual register16_t getWord(uint16_t address);
|
|
|
|
virtual void set(uint16_t address, uint8_t value) {
|
|
ADDRESS() = address;
|
|
reference() = value;
|
|
}
|
|
|
|
virtual void setWord(uint16_t address, register16_t value);
|
|
|
|
virtual uint8_t& reference() {
|
|
uint16_t effective = ADDRESS() & m_addressMask;
|
|
return m_locked[effective] ? placeDATA(m_bus[effective]) : referenceDATA(m_bus[effective]);
|
|
}
|
|
|
|
void clear();
|
|
void loadRom(const std::string& path, uint16_t offset);
|
|
void loadRam(const std::string& path, uint16_t offset);
|
|
|
|
protected:
|
|
std::array<uint8_t, 0x10000> m_bus;
|
|
std::array<bool, 0x10000> m_locked;
|
|
|
|
uint16_t m_addressMask; // Mirror
|
|
uint8_t m_temporary; // Used to simulate ROM
|
|
uint16_t m_address;
|
|
uint8_t* m_data;
|
|
|
|
int loadMemory(const std::string& path, uint16_t offset);
|
|
};
|
|
} |