47 lines
1.3 KiB
C#
47 lines
1.3 KiB
C#
using System;
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using Core.Interfaces;
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namespace Core.Memory
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{
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public class MemoryBus : IMemory
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{
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// The flat 64KB memory space
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private readonly byte[] _memory = new byte[0x10000];
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public byte Read(ushort address)
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{
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return _memory[address];
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}
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public void Write(ushort address, byte value)
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{
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/* ZX Spectrum 48K Memory Map:
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* 0x0000 - 0x3FFF: ROM (16KB) -> Cannot write here!
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* 0x4000 - 0x57FF: Display File (Screen Pixels)
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* 0x5800 - 0x5AFF: Color Attributes
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* 0x5B00 - 0xFFFF: General Purpose RAM
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*/
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if (address < 0x4000)
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{
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// Attempted to write to the ROM area.
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// We simply ignore the write command, just like real hardware.
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return;
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}
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_memory[address] = value;
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}
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// Helper method to load the original Sinclair ROM file
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public void LoadRom(byte[] romData)
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{
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if (romData.Length > 0x4000)
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{
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throw new ArgumentException("ROM file exceeds the 16KB capacity of Bank 0.");
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}
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// Copy the ROM data into the very beginning of the memory array
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Array.Copy(romData, 0, _memory, 0, romData.Length);
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}
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}
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} |