60 lines
1023 B
C#
60 lines
1023 B
C#
using BizHawk.Common;
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namespace BizHawk.Emulation.Cores.Computers.Commodore64.MOS
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{
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// DRAM for the c64
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// 4164 = 64 kbit
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// 4464 = 256 kbit
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// 4864 = 512 kbit
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// for purposes of simplification we'll just
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// use one 4864, the C64 can use sets of 4164 or
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// 4464 typically
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// memory is striped 00/FF at intervals of 0x40
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public sealed class Chip4864
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{
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private int[] _ram;
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public Chip4864()
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{
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_ram = new int[0x10000];
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HardReset();
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}
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public void HardReset()
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{
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// stripe the ram
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for (var i = 0; i < 10000; i++)
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{
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_ram[i] = (i & 0x40) != 0 ? 0xFF : 0x00;
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}
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}
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public int Peek(int addr)
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{
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return _ram[addr];
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}
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public void Poke(int addr, int val)
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{
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_ram[addr] = val;
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}
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public int Read(int addr)
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{
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return _ram[addr];
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}
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public void SyncState(Serializer ser)
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{
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ser.Sync("_ram", ref _ram, useNull: false);
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}
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public void Write(int addr, int val)
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{
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_ram[addr] = val;
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}
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}
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}
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