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Add a initial port of the MC6809 processor to the .Net collection

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Signed-off-by: Adrian Conlon <adrian.conlon@gmail.com>
This commit is contained in:
Adrian Conlon
2019-04-10 19:51:39 +01:00
parent 8b67a827dd
commit 6b33d2b5a5
9 changed files with 1792 additions and 6 deletions
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13
EightBit/Processor.cs
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@ -35,6 +35,15 @@ namespace EightBit
protected byte OpCode { get; set; }
// http://graphics.stanford.edu/~seander/bithacks.html#FixedSignExtend
public static sbyte SignExtend(int b, byte x)
{
var m = (byte)(1 << (b - 1)); // mask can be pre-computed if b is fixed
x = (byte)(x & ((1 << b) - 1)); // (Skip this if bits in x above position b are already zero.)
var result = (x ^ m) - m;
return (sbyte)result;
}
public ref PinLevel RESET() => ref this.resetLine;
public ref PinLevel INT() => ref this.intLine;
@ -178,12 +187,16 @@ namespace EightBit
return this.GetWord();
}
protected Register16 GetWord(Register16 address) => this.GetWord(address.Word);
protected void SetWord(ushort address, Register16 value)
{
this.Bus.Address.Word = address;
this.SetWord(value);
}
protected void SetWord(Register16 address, Register16 value) => this.SetWord(address.Word, value);
protected void Jump(ushort destination) => this.PC.Word = destination;
protected void Call(ushort destination)