67 lines
1.7 KiB
C#
67 lines
1.7 KiB
C#
namespace EMU7800.Core
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{
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/// <summary>
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/// Atari 7800 Absolute bankswitched cartridge
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/// </summary>
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public sealed class Cart78AB : Cart
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{
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//
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// Cart Format Mapping to ROM Address Space
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// Bank0: 0x00000:0x4000
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// Bank1: 0x04000:0x4000 0x4000:0x4000 Bank0-1 (0 on startup)
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// Bank2: 0x08000:0x4000 0x8000:0x4000 Bank2
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// Bank3: 0x0c000:0x4000 0xc000:0x4000 Bank3
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//
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readonly int[] Bank = new int[4];
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#region IDevice Members
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public override byte this[ushort addr]
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{
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get { return ROM[ (Bank[addr >> 14] << 14) | (addr & 0x3fff) ]; }
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set
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{
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if ((addr >> 14) == 2)
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{
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Bank[1] = (value - 1) & 1;
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}
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}
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}
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#endregion
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private Cart78AB()
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{
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}
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public Cart78AB(byte[] romBytes)
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{
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Bank[1] = 0;
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Bank[2] = 2;
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Bank[3] = 3;
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LoadRom(romBytes, 0x10000);
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}
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#region Serialization Members
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public Cart78AB(DeserializationContext input, MachineBase m) : base(input)
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{
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var version = input.CheckVersion(1, 2);
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LoadRom(input.ReadBytes());
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Bank = input.ReadIntegers(4);
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if (version == 1)
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input.ReadInt32();
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}
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public override void GetObjectData(SerializationContext output)
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{
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base.GetObjectData(output);
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output.WriteVersion(2);
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output.Write(ROM);
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output.Write(Bank);
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}
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#endregion
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}
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} |