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58 lines
1.2 KiB
C++
58 lines
1.2 KiB
C++
#pragma once
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#include "stdafx.h"
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#include "MMC3.h"
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class MMC3_123 : public MMC3
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{
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private:
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const uint8_t _security[8] = { 0,3,1,5,6,7,2,4 };
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uint8_t _exReg[2];
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void UpdatePrgMapping() override
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{
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if(_exReg[0] & 0x40) {
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uint8_t bank = (_exReg[0] & 0x05) | ((_exReg[0] & 0x08) >> 2) | ((_exReg[0] & 0x20) >> 2);
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if(_exReg[0] & 0x02) {
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SelectPrgPage4x(0, (bank & 0xFE) << 1);
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} else {
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SelectPrgPage2x(0, bank << 1);
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SelectPrgPage2x(1, bank << 1);
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}
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} else {
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MMC3::UpdatePrgMapping();
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}
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}
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void InitMapper() override
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{
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MMC3::InitMapper();
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_exReg[0] = _exReg[1] = 0;
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AddRegisterRange(0x5001, 0x5FFF, MemoryOperation::Write);
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}
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void StreamState(bool saving) override
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{
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MMC3::StreamState(saving);
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Stream(_exReg[0], _exReg[1]);
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}
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void WriteRegister(uint16_t addr, uint8_t value) override
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{
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if(addr < 0x8000 && addr & 0x0800) {
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if(addr & 0x01) {
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_exReg[1] = value;
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} else {
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_exReg[0] = value;
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}
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UpdatePrgMapping();
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} else if(addr < 0xA000) {
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switch(addr & 0x8001) {
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case 0x8000: MMC3::WriteRegister(0x8000, (value & 0xC0) | (_security[value & 0x07])); break;
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case 0x8001: MMC3::WriteRegister(0x8001, value); break;
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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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}; |