72 lines
1.9 KiB
C#
72 lines
1.9 KiB
C#
//////////////////////////////////////////////////////////////////////////
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// Mapper228 Action 52 //
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//////////////////////////////////////////////////////////////////////////
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using static VirtualNes.MMU;
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using BYTE = System.Byte;
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namespace VirtualNes.Core
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{
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public class Mapper228 : Mapper
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{
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public Mapper228(NES parent) : base(parent)
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{
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}
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public override void Reset()
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{
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SetPROM_32K_Bank(0);
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SetVROM_8K_Bank(0);
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}
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//void Mapper228::Write(WORD addr, BYTE data)
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public override void Write(ushort addr, byte data)
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{
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BYTE prg = (byte)((addr & 0x0780) >> 7);
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switch ((addr & 0x1800) >> 11)
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{
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case 1:
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prg |= 0x10;
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break;
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case 3:
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prg |= 0x20;
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break;
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}
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if ((addr & 0x0020) != 0)
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{
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prg <<= 1;
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if ((addr & 0x0040) != 0)
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{
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prg++;
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}
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SetPROM_8K_Bank(4, prg * 4 + 0);
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SetPROM_8K_Bank(5, prg * 4 + 1);
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SetPROM_8K_Bank(6, prg * 4 + 0);
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SetPROM_8K_Bank(7, prg * 4 + 1);
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}
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else
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{
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SetPROM_8K_Bank(4, prg * 4 + 0);
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SetPROM_8K_Bank(5, prg * 4 + 1);
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SetPROM_8K_Bank(6, prg * 4 + 2);
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SetPROM_8K_Bank(7, prg * 4 + 3);
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}
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SetVROM_8K_Bank(((addr & 0x000F) << 2) | (data & 0x03));
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if ((addr & 0x2000) != 0)
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{
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SetVRAM_Mirror(VRAM_HMIRROR);
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}
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else
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{
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SetVRAM_Mirror(VRAM_VMIRROR);
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}
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}
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}
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}
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