EightBitNet/EightBit/BigEndianProcessor.cs

75 lines
2.1 KiB
C#

// <copyright file="BigEndianProcessor.cs" company="Adrian Conlon">
// Copyright (c) Adrian Conlon. All rights reserved.
// </copyright>
namespace EightBit
{
public abstract class BigEndianProcessor : Processor
{
protected BigEndianProcessor(Bus memory)
: base(memory)
{
}
public override Register16 PeekWord(ushort address)
{
var high = this.Bus.Peek(address);
var low = this.Bus.Peek(++address);
return new Register16(low, high);
}
public override void PokeWord(ushort address, Register16 value)
{
this.Bus.Poke(address, value.Low);
this.Bus.Poke(++address, value.High);
}
protected override Register16 FetchWord()
{
var high = this.FetchByte();
var low = this.FetchByte();
return new Register16(low, high);
}
protected override Register16 GetWord()
{
var high = this.BusRead();
++this.Bus.Address();
var low = this.BusRead();
return new Register16(low, high);
}
protected override Register16 GetWordPaged(byte page, byte offset)
{
var high = this.BusRead(offset, page);
var low = this.BusRead(++offset, page);
return new Register16(low, high);
}
protected override Register16 PopWord()
{
var high = this.Pop();
var low = this.Pop();
return new Register16(low, high);
}
protected override void PushWord(Register16 value)
{
this.Push(value.Low);
this.Push(value.High);
}
protected override void SetWord(Register16 value)
{
this.BusWrite(value.High);
++this.Bus.Address();
this.BusWrite(value.Low);
}
protected override void SetWordPaged(byte page, byte offset, Register16 value)
{
this.BusWrite(offset, page, value.High);
this.BusWrite(++offset, page, value.Low);
}
}
}