Mesen/Core/MMC3_215.h

115 lines
2.8 KiB
C++

#pragma once
#include "stdafx.h"
#include "MMC3.h"
//Unif: UNL-8237
class MMC3_215 : public MMC3
{
protected:
const uint8_t _lutReg[8][8] = {
{ 0, 1, 2, 3, 4, 5, 6, 7 },
{ 0, 2, 6, 1, 7, 3, 4, 5 },
{ 0, 5, 4, 1, 7, 2, 6, 3 },
{ 0, 6, 3, 7, 5, 2, 4, 1 },
{ 0, 2, 5, 3, 6, 1, 7, 4 },
{ 0, 1, 2, 3, 4, 5, 6, 7 },
{ 0, 1, 2, 3, 4, 5, 6, 7 },
{ 0, 1, 2, 3, 4, 5, 6, 7 },
};
const uint8_t _lutAddr[8][8] =
{
{ 0, 1, 2, 3, 4, 5, 6, 7 },
{ 3, 2, 0, 4, 1, 5, 6, 7 },
{ 0, 1, 2, 3, 4, 5, 6, 7 },
{ 5, 0, 1, 2, 3, 7, 6, 4 },
{ 3, 1, 0, 5, 2, 4, 6, 7 },
{ 0, 1, 2, 3, 4, 5, 6, 7 },
{ 0, 1, 2, 3, 4, 5, 6, 7 },
{ 0, 1, 2, 3, 4, 5, 6, 7 },
};
uint8_t _exRegs[3];
uint16_t RegisterStartAddress() override { return 0x5000; }
uint16_t RegisterEndAddress() override { return 0xFFFF; }
void InitMapper() override
{
_exRegs[0] = 0;
_exRegs[1] = 3;
_exRegs[2] = 0;
MMC3::InitMapper();
}
void StreamState(bool saving) override
{
MMC3::StreamState(saving);
Stream(_exRegs[0], _exRegs[1], _exRegs[2]);
}
void SelectCHRPage(uint16_t slot, uint16_t page, ChrMemoryType memoryType) override
{
if(_exRegs[0] & 0x40) {
MMC3::SelectCHRPage(slot, ((_exRegs[1] & 0x0C) << 6) | (page & 0x7F) | ((_exRegs[1] & 0x20) << 2), memoryType);
} else {
MMC3::SelectCHRPage(slot, ((_exRegs[1] & 0x0C) << 6) | page, memoryType);
}
}
void SelectPRGPage(uint16_t slot, uint16_t page, PrgMemoryType memoryType = PrgMemoryType::PrgRom) override
{
uint8_t sbank = 0;
uint8_t bank = 0;
uint8_t mask = 0;
if(_exRegs[0] & 0x40) {
mask = 0x0F;
sbank = (_exRegs[1] & 0x10);
if(_exRegs[0] & 0x80) {
bank = ((_exRegs[1] & 0x03) << 4) | (_exRegs[0] & 0x07) | (sbank >> 1);
}
} else {
mask = 0x1F;
if(_exRegs[0] & 0x80) {
bank = ((_exRegs[1] & 0x03) << 4) | (_exRegs[0] & 0x0F);
}
}
if(_exRegs[0] & 0x80) {
bank <<= 1;
if(_exRegs[0] & 0x20) {
MMC3::SelectPRGPage(0, bank);
MMC3::SelectPRGPage(1, bank + 1);
MMC3::SelectPRGPage(2, bank + 2);
MMC3::SelectPRGPage(3, bank + 3);
} else {
MMC3::SelectPRGPage(0, bank);
MMC3::SelectPRGPage(1, bank + 1);
MMC3::SelectPRGPage(2, bank);
MMC3::SelectPRGPage(3, bank + 1);
}
} else {
MMC3::SelectPRGPage(slot, ((_exRegs[1] & 0x03) << 5) | (page & mask) | sbank);
}
}
void WriteRegister(uint16_t addr, uint8_t value) override
{
if(addr < 0x8000) {
switch(addr) {
case 0x5000: _exRegs[0] = value; UpdateState(); break;
case 0x5001: _exRegs[1] = value; UpdateState(); break;
case 0x5007: _exRegs[2] = value; break;
}
} else {
uint8_t lutValue = _lutAddr[_exRegs[2]][((addr >> 12) & 0x06) | (addr & 0x01)];
addr = (lutValue & 0x01) | ((lutValue & 0x06) << 12) | 0x8000;
if(lutValue == 0) {
value = (value & 0xC0) | (_lutReg[_exRegs[2]][value & 0x07]);
}
MMC3::WriteRegister(addr, value);
}
}
};