Mesen/Core/MMC3_444.h
2023-05-12 20:37:50 -05:00

82 lines
2.1 KiB
C++

#pragma once
#include "stdafx.h"
#include "MMC3.h"
// NES 2.0 Mapper 444 denotes the NC7000M multicart circuit board.
// Its UNIF board name is BMC-BS-110, which is the name of a different PCB whose name was mixed-up.
class MMC3_444 : public MMC3
{
private:
uint8_t _exRegs;
protected:
uint32_t GetDipSwitchCount() override { return 2; }
uint16_t RegisterStartAddress() override { return 0x6000; }
uint16_t RegisterEndAddress() override { return 0xFFFF; }
bool AllowRegisterRead() override { return true; }
void InitMapper() override
{
RemoveRegisterRange(0x6000, 0x7FFF, MemoryOperation::Read);
MMC3::InitMapper();
}
void Reset(bool softreset) override
{
_exRegs = 0;
MMC3::UpdateState();
}
void StreamState(bool saving) override
{
MMC3::StreamState(saving);
Stream(_exRegs);
}
void SelectCHRPage(uint16_t slot, uint16_t page, ChrMemoryType memoryType = ChrMemoryType::Default) override
{
uint8_t mask = (_romInfo.SubMapperID & 0x01) ? 0xFF : 0x7F;
uint16_t outerBank = (_exRegs << 7) & ((_romInfo.SubMapperID & 0x01) ? 0x00 : 0x80); // A17
outerBank |= ((_exRegs << ((_romInfo.SubMapperID & 0x02) ? 4 : 7)) & 0x100); // A18
MMC3::SelectCHRPage(slot, (outerBank & ~mask) | (page & mask), memoryType);
}
void SelectPRGPage(uint16_t slot, uint16_t page, PrgMemoryType memoryType = PrgMemoryType::PrgRom) override
{
if(_exRegs & 0x04) {
page = (_exRegs << 4) | (MMC3::_registers[6] & 0x0F);
if(_exRegs & 0x08) {
page &= 0xFE;
MMC3::SelectPrgPage2x(0, page, memoryType);
MMC3::SelectPrgPage2x(1, page, memoryType);
} else {
page &= 0xFC;
MMC3::SelectPrgPage4x(0, page, memoryType);
}
} else {
MMC3::SelectPRGPage(slot, (_exRegs << 4) | (page & 0x0F), memoryType);
}
}
uint8_t ReadRegister(uint16_t addr) override
{
if((_exRegs & 0x0C) == 0x08) {
return GetDipSwitches();
}
return InternalReadRam(addr);
}
void WriteRegister(uint16_t addr, uint8_t value) override
{
if(addr < 0x8000) {
/*if(MMC3::CanWriteToWorkRam()) */{
_exRegs = (uint8_t)addr;
MMC3::UpdatePrgMapping();
MMC3::UpdateChrMapping();
}
} else {
MMC3::WriteRegister(addr, value);
}
}
};