41 lines
920 B
C#
41 lines
920 B
C#
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namespace BizHawk.Emulation.Cores.Sega.MasterSystem
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{
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public partial class SMS
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{
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byte[] ExtRam;
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int ExtRamMask;
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byte ReadMemoryExt(ushort address)
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{
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byte ret;
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if (address < 0x8000)
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ret = RomData[address];
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else if (address < 0xC000)
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ret = ExtRam[address & ExtRamMask];
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else
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ret = SystemRam[address & RamSizeMask];
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CoreComm.MemoryCallbackSystem.CallRead(address);
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return ret;
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}
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void WriteMemoryExt(ushort address, byte value)
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{
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if (address < 0xC000 && address >= 0x8000)
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ExtRam[address & ExtRamMask] = value;
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else if (address >= 0xC000)
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SystemRam[address & RamSizeMask] = value;
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CoreComm.MemoryCallbackSystem.CallWrite((uint)address);
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}
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void InitExt2kMapper(int size)
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{
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ExtRam = new byte[size];
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ExtRamMask = size - 1;
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Cpu.ReadMemory = ReadMemoryExt;
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Cpu.WriteMemory = WriteMemoryExt;
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}
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}
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}
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