Mesen/Core/MMC4.h

#pragma once
#include "stdafx.h"
#include "MMC2.h"

class MMC4 : public MMC2
{
	protected:
		virtual uint16_t GetPRGPageSize() override { return 0x4000; }
		virtual uint16_t GetCHRPageSize() override {	return 0x1000; }

		virtual void InitMapper() override 
		{
			_leftLatch = 1;
			_rightLatch = 1;
			_leftChrPage[0] = GetPowerOnByte() & 0x1F;
			_leftChrPage[1] = GetPowerOnByte() & 0x1F;
			_rightChrPage[0] = GetPowerOnByte() & 0x1F;
			_rightChrPage[1] = GetPowerOnByte() & 0x1F;
			_needChrUpdate = false;

			SelectPRGPage(1, -1);
		}
		
	public:
		virtual void NotifyVRAMAddressChange(uint16_t addr) override
		{
			if(_needChrUpdate) {
				SelectCHRPage(0, _leftChrPage[_leftLatch]);
				SelectCHRPage(1, _rightChrPage[_rightLatch]);
				_needChrUpdate = false;
			}

			if(addr >= 0x0FD8 && addr <= 0x0FDF) {
				_leftLatch = 0;
				_needChrUpdate = true;
			} else if(addr >= 0x0FE8 && addr <= 0x0FEF) {
				_leftLatch = 1;
				_needChrUpdate = true;
			} else if(addr >= 0x1FD8 && addr <= 0x1FDF) {
				_rightLatch = 0;
				_needChrUpdate = true;
			} else if(addr >= 0x1FE8 && addr <= 0x1FEF) {
				_rightLatch = 1;
				_needChrUpdate = true;
			}
		}
};