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https://github.com/SourMesen/Mesen2.git
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44 lines
No EOL
1.1 KiB
C++
44 lines
No EOL
1.1 KiB
C++
#pragma once
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#include "pch.h"
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#include "NES/Mappers/Nintendo/MMC3.h"
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class Mapper91 : public MMC3
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{
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protected:
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uint16_t RegisterStartAddress() override { return 0x6000; }
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uint16_t RegisterEndAddress() override { return 0x7FFF; }
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uint16_t GetPrgPageSize() override { return 0x2000; }
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uint16_t GetChrPageSize() override { return 0x800; }
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void InitMapper() override
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{
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SelectPrgPage(2, -2);
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SelectPrgPage(3, -1);
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}
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void UpdateState() override
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{
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//Do nothing, we are only using MMC3 code to emulate the IRQs
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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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switch(addr & 0x7003) {
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case 0x6000: SelectChrPage(0, value); break;
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case 0x6001: SelectChrPage(1, value); break;
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case 0x6002: SelectChrPage(2, value); break;
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case 0x6003: SelectChrPage(3, value); break;
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case 0x7000: SelectPrgPage(0, value & 0x0F); break;
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case 0x7001: SelectPrgPage(1, value & 0x0F); break;
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case 0x7002:
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MMC3::WriteRegister(0xE000, value);
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break;
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case 0x7003:
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MMC3::WriteRegister(0xC000, 0x07);
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MMC3::WriteRegister(0xC001, value);
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MMC3::WriteRegister(0xE001, value);
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break;
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}
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}
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}; |