46 lines
917 B
C++
46 lines
917 B
C++
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/////////////////////////////////////////////////////////////////////
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// Mapper 231
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void NES_mapper231::Reset()
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{
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// set CPU bank pointers
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set_CPU_banks(0,1,2,3);
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// set PPU bank pointers
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if(num_1k_VROM_banks)
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{
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set_PPU_banks(0,1,2,3,4,5,6,7);
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}
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}
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void NES_mapper231::MemoryWrite(uint32 addr, uint8 data)
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{
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if(addr & 0x0020)
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{
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uint8 prg_bank = (uint8)(addr >> 1) & 0x0F;
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set_CPU_bank4(prg_bank*4+0);
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set_CPU_bank5(prg_bank*4+1);
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set_CPU_bank6(prg_bank*4+2);
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set_CPU_bank7(prg_bank*4+3);
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}
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else
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{
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uint8 prg_bank = addr & 0x001E;
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set_CPU_bank4(prg_bank*2+0);
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set_CPU_bank5(prg_bank*2+1);
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set_CPU_bank6(prg_bank*2+0);
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set_CPU_bank7(prg_bank*2+1);
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}
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if(addr & 0x0080)
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{
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set_mirroring(NES_PPU::MIRROR_HORIZ);
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}
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else
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{
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set_mirroring(NES_PPU::MIRROR_VERT);
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}
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}
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/////////////////////////////////////////////////////////////////////
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