EightBitNet/EightBit/Register16.cs
Adrian Conlon 6b33d2b5a5 Add a initial port of the MC6809 processor to the .Net collection
Signed-off-by: Adrian Conlon <adrian.conlon@gmail.com>
2019-04-10 19:51:39 +01:00

97 lines
2.2 KiB
C#

// <copyright file="Register16.cs" company="Adrian Conlon">
// Copyright (c) Adrian Conlon. All rights reserved.
// </copyright>
namespace EightBit
{
using System.Diagnostics;
[DebuggerDisplay("Word = {Word}")]
public class Register16
{
private byte low;
private byte high;
public Register16(byte low, byte high)
{
this.Low = low;
this.High = high;
}
public Register16(ushort value)
{
this.Low = Chip.LowByte(value);
this.High = Chip.HighByte(value);
}
public Register16()
: this((ushort)0)
{
}
public Register16(int value)
: this((ushort)value)
{
}
public Register16(uint value)
: this((ushort)value)
{
}
public Register16(byte low)
: this(low, 0)
{
}
public Register16(Register16 rhs)
{
this.Low = rhs.Low;
this.High = rhs.High;
}
public ushort Word
{
get => (ushort)(this.Low | Chip.PromoteByte(this.High));
set
{
this.Low = Chip.LowByte(value);
this.High = Chip.HighByte(value);
}
}
public ref byte Low => ref this.low;
public ref byte High => ref this.high;
public static Register16 operator ++(Register16 value) => Increment(value);
public static Register16 operator --(Register16 value) => Decrement(value);
public static bool operator ==(Register16 left, Register16 right) => left.Equals(right);
public static bool operator !=(Register16 left, Register16 right) => !(left == right);
public static Register16 Increment(Register16 value)
{
++value.Word;
return value;
}
public static Register16 Decrement(Register16 value)
{
--value.Word;
return value;
}
public override bool Equals(object obj)
{
var rhs = obj as Register16;
return rhs == null ? false : rhs.Low == this.Low && rhs.High == this.High;
}
public override int GetHashCode() => this.Word;
}
}