Mesen/Core/CNROM.h

44 lines
1.1 KiB
C++

#pragma once
#include "stdafx.h"
#include "BaseMapper.h"
class CNROM : public BaseMapper
{
private:
bool _enableCopyProtection;
protected:
virtual uint16_t GetPRGPageSize() override { return 0x8000; }
virtual uint16_t GetCHRPageSize() override { return 0x2000; }
void InitMapper() override
{
SelectPRGPage(0, 0);
SelectCHRPage(0, 0);
//Needed for mighty bomb jack (j)
_vramOpenBusValue = 0xFF;
}
bool HasBusConflicts() override { return (_mapperID == 3 && _subMapperID == 2) || _mapperID == 185; }
void WriteRegister(uint16_t addr, uint8_t value) override
{
if(_enableCopyProtection) {
//"if C AND $0F is nonzero, and if C does not equal $13: CHR is enabled"
//Seicross (mapper 185 version) is assigned to submapper 16 (not a real submapper) to make it work properly
if((_subMapperID == 16 && !(value & 0x01)) || (_subMapperID == 0 && (value & 0x0F) != 0 && value != 0x13)) {
SelectCHRPage(0, 0);
} else {
RemovePpuMemoryMapping(0x0000, 0x1FFF);
}
} else {
SelectCHRPage(0, value);
}
}
public:
CNROM(bool enableCopyProtection) : _enableCopyProtection(enableCopyProtection)
{
}
};