EightBitNet/EightBit/Bus.cs
Adrian Conlon d4a35c402c A few small consistency updates:
1) Drop Get/SetPagedByte in favour of normal BusRead/Write
2) Tidy some "using" statements
3) More "expression body" usage, if possible
4) Use field initialisation, rather than construction, if possible
5) Correct IntelProcessor register set/get methods (there were remnants of "copy pasta" code)

Signed-off-by: Adrian Conlon <Adrian.conlon@gmail.com>
2019-02-03 20:29:52 +00:00

97 lines
3.0 KiB
C#

namespace EightBit
{
using System;
abstract public class Bus : IMapper
{
private byte data;
private ushort address;
public event EventHandler<EventArgs> WritingByte;
public event EventHandler<EventArgs> WrittenByte;
public event EventHandler<EventArgs> ReadingByte;
public event EventHandler<EventArgs> ReadByte;
public byte Data { get => data; set => data = value; }
public ushort Address { get => address; set => address = value; }
public abstract MemoryMapping Mapping(ushort absolute);
public byte Peek() => Reference();
public byte Peek(ushort absolute) => Reference(absolute);
public byte Peek(byte low, byte high) => Reference(low, high);
public void Poke(byte value) => Reference() = value;
public byte Poke(ushort absolute, byte value) => Reference(absolute) = value;
public byte Poke(byte low, byte high, byte value) => Reference(low, high) = value;
public byte Read()
{
OnReadingByte();
var returned = Data = Reference();
OnReadByte();
return returned;
}
public byte Read(ushort absolute)
{
Address = absolute;
return Read();
}
public byte Read(byte low, byte high) => Read(Chip.MakeWord(low, high));
public void Write()
{
OnWritingByte();
Reference() = Data;
OnWrittenByte();
}
public void Write(byte value)
{
Data = value;
Write();
}
public void Write(ushort absolute, byte value)
{
Address = absolute;
Write(value);
}
public void Write(byte low, byte high, byte value) => Write(Chip.MakeWord(low, high), value);
public virtual void RaisePOWER() {}
public virtual void LowerPOWER() {}
public abstract void Initialize();
protected virtual void OnWritingByte() => WritingByte?.Invoke(this, EventArgs.Empty);
protected virtual void OnWrittenByte() => WrittenByte?.Invoke(this, EventArgs.Empty);
protected virtual void OnReadingByte() => ReadingByte?.Invoke(this, EventArgs.Empty);
protected virtual void OnReadByte() => ReadByte?.Invoke(this, EventArgs.Empty);
protected ref byte Reference(ushort absolute)
{
var mapped = Mapping(absolute);
var offset = (ushort)((absolute - mapped.Begin) & mapped.Mask);
if (mapped.Access == AccessLevel.ReadOnly)
{
Data = mapped.Memory.Peek(offset);
return ref data;
}
return ref mapped.Memory.Reference(offset);
}
protected ref byte Reference() => ref Reference(Address);
protected ref byte Reference(byte low, byte high) => ref Reference(Chip.MakeWord(low, high));
//[[nodiscard]] static std::map<uint16_t, std::vector<uint8_t>> parseHexFile(std::string path);
//void loadHexFile(std::string path);
}
}