Mesen-X/Core/Mapper225.h
2022-03-17 01:04:19 +08:00

53 lines
1.2 KiB
C++

#pragma once
#include "stdafx.h"
#include "BaseMapper.h"
class Mapper225 : public BaseMapper
{
protected:
virtual uint16_t GetPRGPageSize() override { return 0x4000; }
virtual uint16_t GetCHRPageSize() override { return 0x2000; }
bool AllowRegisterRead() override { return true; }
uint8_t RAM[4];
void InitMapper() override
{
memset(RAM, 0, sizeof(RAM));
SelectPRGPage(0, 0);
SelectPRGPage(1, 1);
SelectCHRPage(0, 0);
AddRegisterRange(0x5800, 0x5FFF, MemoryOperation::Any);
RemoveRegisterRange(0x8000, 0xFFFF, MemoryOperation::Read);
}
uint8_t ReadRegister(uint16_t addr) override
{
return RAM[addr & 0x03] & 0x0F;
}
void WriteRegister(uint16_t addr, uint8_t value) override
{
if(addr <= 0x5FFF) {
RAM[addr & 0x03] = value;
return;
}
uint8_t highBit = (addr >> 8) & 0x40;
uint8_t prgPage = ((addr >> 6) & 0x3F) | highBit;
if(addr & 0x1000) {
SelectPRGPage(0, prgPage);
SelectPRGPage(1, prgPage);
} else {
SelectPRGPage(0, prgPage & 0xFE);
SelectPRGPage(1, (prgPage & 0xFE) + 1);
}
SelectCHRPage(0, (addr & 0x3F) | highBit);
SetMirroringType(addr & 0x2000 ? MirroringType::Horizontal : MirroringType::Vertical);
}
};