Mesen2/Core/NES/Mappers/Mmc3Variants/MMC3_199.h
2022-09-08 21:29:52 -04:00

68 lines
No EOL
1.8 KiB
C++

#pragma once
#include "pch.h"
#include "NES/Mappers/Nintendo/MMC3.h"
class MMC3_199 : public MMC3
{
private:
uint8_t _exRegs[4] = {};
protected:
uint32_t GetChrRamSize() override { return 0x2000; }
uint16_t GetChrRamPageSize() override { return 0x400; }
void InitMapper() override
{
_exRegs[0] = 0xFE;
_exRegs[1] = 0xFF;
_exRegs[2] = 1;
_exRegs[3] = 3;
MMC3::InitMapper();
}
void Serialize(Serializer& s) override
{
MMC3::Serialize(s);
SVArray(_exRegs, 4);
}
void WriteRegister(uint16_t addr, uint8_t value) override
{
if(addr == 0x8001 && (GetState().Reg8000 & 0x08)) {
_exRegs[GetState().Reg8000 & 0x03] = value;
UpdatePrgMapping();
UpdateChrMapping();
} else {
MMC3::WriteRegister(addr, value);
}
}
void UpdateMirroring() override
{
switch(GetState().RegA000 & 0x03) {
case 0: SetMirroringType(MirroringType::Vertical); break;
case 1: SetMirroringType(MirroringType::Horizontal); break;
case 2: SetMirroringType(MirroringType::ScreenAOnly); break;
case 3: SetMirroringType(MirroringType::ScreenBOnly); break;
}
}
void UpdatePrgMapping() override
{
MMC3::UpdatePrgMapping();
SelectPrgPage(2, _exRegs[0]);
SelectPrgPage(3, _exRegs[1]);
}
void SelectChrPage(uint16_t slot, uint16_t page, ChrMemoryType memoryType) override
{
MMC3::SelectChrPage(slot, page, page < 8 ? ChrMemoryType::ChrRam : ChrMemoryType::ChrRom);
MMC3::SelectChrPage(0, _registers[0], _registers[0] < 8 ? ChrMemoryType::ChrRam : ChrMemoryType::ChrRom);
MMC3::SelectChrPage(1, _exRegs[2], _exRegs[2] < 8 ? ChrMemoryType::ChrRam : ChrMemoryType::ChrRom);
MMC3::SelectChrPage(2, _registers[1], _registers[1] < 8 ? ChrMemoryType::ChrRam : ChrMemoryType::ChrRom);
MMC3::SelectChrPage(3, _exRegs[3], _exRegs[3] < 8 ? ChrMemoryType::ChrRam : ChrMemoryType::ChrRom);
}
};