#pragma once #include "pch.h" #include "NES/Mappers/Nintendo/MMC3.h" class MMC3_254 : public MMC3 { private: uint8_t _exRegs[2] = {}; protected: bool AllowRegisterRead() override { return true; } void InitMapper() override { MMC3::InitMapper(); AddRegisterRange(0x6000, 0x7FFF, MemoryOperation::Read); RemoveRegisterRange(0x8000, 0xFFFF, MemoryOperation::Read); } void Serialize(Serializer& s) override { MMC3::Serialize(s); SV(_exRegs[0]); SV(_exRegs[1]); } uint8_t ReadRegister(uint16_t addr) override { uint8_t value = InternalReadRam(addr); if(_exRegs[0]) { return value; } else { return value ^ _exRegs[1]; } } void WriteRegister(uint16_t addr, uint8_t value) override { switch(addr) { case 0x8000: _exRegs[0] = 0xFF; break; case 0xA001: _exRegs[1] = value; break; } MMC3::WriteRegister(addr, value); } };