105 lines
2.6 KiB
C#
105 lines
2.6 KiB
C#
//////////////////////////////////////////////////////////////////////////
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// Mapper234 Maxi-15 //
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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 Mapper234 : Mapper
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{
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BYTE[] reg = new byte[2];
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public Mapper234(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, 1, 2, 3);
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reg[0] = 0;
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reg[1] = 0;
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}
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//void Mapper234::Read(WORD addr, BYTE data)
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public override void Read(ushort addr, byte data)
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{
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if (addr >= 0xFF80 && addr <= 0xFF9F)
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{
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if (reg[0] != 0)
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{
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reg[0] = data;
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SetBank();
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}
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}
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if (addr >= 0xFFE8 && addr <= 0xFFF7)
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{
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reg[1] = data;
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SetBank();
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}
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}
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//void Mapper234::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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if (addr >= 0xFF80 && addr <= 0xFF9F)
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{
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if (reg[0] == 0)
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{
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reg[0] = data;
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SetBank();
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}
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}
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if (addr >= 0xFFE8 && addr <= 0xFFF7)
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{
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reg[1] = data;
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SetBank();
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}
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}
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void SetBank()
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{
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if ((reg[0] & 0x80) != 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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if ((reg[0] & 0x40) != 0)
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{
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SetPROM_32K_Bank((reg[0] & 0x0E) | (reg[1] & 0x01));
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SetVROM_8K_Bank(((reg[0] & 0x0E) << 2) | ((reg[1] >> 4) & 0x07));
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}
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else
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{
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SetPROM_32K_Bank(reg[0] & 0x0F);
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SetVROM_8K_Bank(((reg[0] & 0x0F) << 2) | ((reg[1] >> 4) & 0x03));
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}
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}
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public override bool IsStateSave()
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{
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return true;
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}
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//void Mapper234::SaveState(LPBYTE p)
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public override void SaveState(byte[] p)
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{
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p[0] = reg[0];
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p[1] = reg[1];
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}
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//void Mapper234::LoadState(LPBYTE p)
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public override void LoadState(byte[] p)
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{
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reg[0] = p[0];
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reg[1] = p[1];
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}
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}
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}
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