Mesen/Core/Hp898f.h
2016-11-10 16:57:19 -05:00

45 lines
1.1 KiB
C++

#pragma once
#include "stdafx.h"
#include "BaseMapper.h"
class Hp898f : public BaseMapper
{
private:
uint8_t _regs[2];
protected:
uint16_t GetPRGPageSize() override { return 0x4000; }
uint16_t GetCHRPageSize() override { return 0x2000; }
uint16_t RegisterStartAddress() override { return 0x6000; }
uint16_t RegisterEndAddress() override { return 0xFFFF; }
void InitMapper() override
{
_regs[0] = _regs[1] = 0;
UpdateState();
}
void StreamState(bool saving) override
{
BaseMapper::StreamState(saving);
Stream(_regs[0], _regs[1]);
}
void UpdateState()
{
uint8_t prgReg = (_regs[1] >> 3) & 7;
uint8_t prgMask = (_regs[1] >> 4) & 4;
SelectCHRPage(0, (((_regs[0] >> 4) & 0x07) & ~(((_regs[0] & 0x01) << 2) | (_regs[0] & 0x02))));
SelectPRGPage(0, prgReg & (~prgMask));
SelectPRGPage(1, prgReg | prgMask);
SetMirroringType(_regs[1] & 0x80 ? MirroringType::Vertical : MirroringType::Horizontal);
}
void WriteRegister(uint16_t addr, uint8_t value) override
{
if((addr & 0x6000) == 0x6000) {
_regs[(addr & 0x04) >> 2] = value;
UpdateState();
}
}
};