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94 lines
2.3 KiB
C++
94 lines
2.3 KiB
C++
#pragma once
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#include "stdafx.h"
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#include "MMC3.h"
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class MMC3_187: public MMC3
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{
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private:
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uint8_t _exRegs[2];
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protected:
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virtual bool AllowRegisterRead() override { return true; }
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virtual void InitMapper() override
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{
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MMC3::InitMapper();
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memset(_exRegs, 0, sizeof(_exRegs));
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AddRegisterRange(0x5000, 0x5FFF, MemoryOperation::Any);
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AddRegisterRange(0x6000, 0x6FFF, MemoryOperation::Write);
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RemoveRegisterRange(0x8000, 0xFFFF, MemoryOperation::Read);
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}
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virtual void SelectCHRPage(uint16_t slot, uint16_t page, ChrMemoryType memoryType = ChrMemoryType::Default) override
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{
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if((_chrMode && slot >= 4) || (!_chrMode && slot < 4)) {
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page |= 0x100;
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}
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BaseMapper::SelectCHRPage(slot, page);
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}
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virtual void SelectPRGPage(uint16_t slot, uint16_t page, PrgMemoryType memoryType = PrgMemoryType::PrgRom) override
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{
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if(!(_exRegs[0] & 0x80)) {
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BaseMapper::SelectPRGPage(slot, page & 0x3F, memoryType);
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} else {
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uint16_t page = _exRegs[0] & 0x1F;
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if(_exRegs[0] & 0x20) {
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if(_exRegs[0] & 0x40) {
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page &= 0xFC;
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BaseMapper::SelectPRGPage(0, page);
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BaseMapper::SelectPRGPage(1, page+1);
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BaseMapper::SelectPRGPage(2, page+2);
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BaseMapper::SelectPRGPage(3, page+3);
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} else {
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page &= 0xFE;
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BaseMapper::SelectPRGPage(0, (page << 1));
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BaseMapper::SelectPRGPage(1, (page << 1) + 1);
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BaseMapper::SelectPRGPage(2, (page << 1) + 2);
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BaseMapper::SelectPRGPage(3, (page << 1) + 3);
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}
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} else {
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BaseMapper::SelectPRGPage(0, (page << 1));
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BaseMapper::SelectPRGPage(1, (page << 1) + 1);
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BaseMapper::SelectPRGPage(2, (page << 1));
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BaseMapper::SelectPRGPage(3, (page << 1) + 1);
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}
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}
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}
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virtual uint8_t ReadRegister(uint16_t addr) override
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{
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uint8_t security[4] = { 0x83,0x83,0x42,0x00 };
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return security[_exRegs[1] & 0x03];
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}
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virtual void WriteRegister(uint16_t addr, uint8_t value) override
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{
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if(addr < 0x8000) {
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if(addr == 0x5000 || addr == 0x6000) {
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_exRegs[0] = value;
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MMC3::UpdatePrgMapping();
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}
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} else {
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if(addr == 0x8000) {
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_exRegs[1] = 1;
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MMC3::WriteRegister(addr, value);
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} else if(addr == 0x8001) {
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if(_exRegs[1] == 1) {
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MMC3::WriteRegister(addr, value);
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}
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} else {
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MMC3::WriteRegister(addr, value);
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}
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}
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}
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virtual void StreamState(bool saving) override
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{
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MMC3::StreamState(saving);
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Stream(_exRegs[0], _exRegs[1]);
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}
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}; |