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53 lines
1.2 KiB
C++
53 lines
1.2 KiB
C++
#pragma once
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#include "stdafx.h"
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#include "BaseMapper.h"
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class Mapper225 : public BaseMapper
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{
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protected:
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virtual uint16_t GetPRGPageSize() override { return 0x4000; }
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virtual uint16_t GetCHRPageSize() override { return 0x2000; }
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bool AllowRegisterRead() override { return true; }
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uint8_t RAM[4];
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void InitMapper() override
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{
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memset(RAM, 0, sizeof(RAM));
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SelectPRGPage(0, 0);
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SelectPRGPage(1, 1);
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SelectCHRPage(0, 0);
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AddRegisterRange(0x5800, 0x5FFF, MemoryOperation::Any);
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RemoveRegisterRange(0x8000, 0xFFFF, MemoryOperation::Read);
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}
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uint8_t ReadRegister(uint16_t addr) override
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{
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return RAM[addr & 0x03] & 0x0F;
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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 <= 0x5FFF) {
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RAM[addr & 0x03] = value;
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return;
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}
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uint8_t highBit = (addr >> 8) & 0x40;
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uint8_t prgPage = ((addr >> 6) & 0x3F) | highBit;
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if(addr & 0x1000) {
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SelectPRGPage(0, prgPage);
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SelectPRGPage(1, prgPage);
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} else {
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SelectPRGPage(0, prgPage & 0xFE);
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SelectPRGPage(1, (prgPage & 0xFE) + 1);
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}
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SelectCHRPage(0, (addr & 0x3F) | highBit);
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SetMirroringType(addr & 0x2000 ? MirroringType::Horizontal : MirroringType::Vertical);
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}
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};
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