6502/EightBitNet
1
0
Fork 0
mirror of https://github.com/MoleskiCoder/EightBitNet.git synced 2026-04-20 06:16:43 +00:00
Code Issues Projects Releases Wiki Activity

Try to minimise use of "Word" from Register16

Browse Source
This commit is contained in:
Adrian Conlon
2024-06-30 12:30:07 +01:00
parent 325bee8539
commit d8fad7b988
8 changed files with 157 additions and 68 deletions
Download Patch File Download Diff File Expand all files Collapse all files
EightBit/IntelProcessor.cs
+46 -13
View File
@@ -127,21 +127,32 @@ namespace EightBit
this.Jump(0);
}
protected sealed override void Push(byte value) => this.MemoryWrite(--this.SP.Word, value);
protected sealed override void Push(byte value)
{
--this.SP.Word;
this.MemoryWrite(this.SP, value);
}
protected sealed override byte Pop() => this.MemoryRead(this.SP.Word++);
protected sealed override byte Pop()
{
var returned = this.MemoryRead(this.SP);
this.SP.Word++;
return returned;
}
protected sealed override Register16 GetWord()
{
var returned = base.GetWord();
this.MEMPTR.Word = this.Bus.Address.Word;
this.MEMPTR.Low = this.Bus.Address.Low;
this.MEMPTR.High = this.Bus.Address.High;
return returned;
}
protected sealed override void SetWord(Register16 value)
{
base.SetWord(value);
this.MEMPTR.Word = this.Bus.Address.Word;
this.MEMPTR.Low = this.Bus.Address.Low;
this.MEMPTR.High = this.Bus.Address.High;
}
////
@@ -150,15 +161,15 @@ namespace EightBit
{
this.MEMPTR.Low = address;
this.MEMPTR.High = 0;
this.Call(this.MEMPTR.Word);
this.Call(this.MEMPTR);
}
protected bool CallConditional(bool condition)
{
this.MEMPTR.Word = this.FetchWord().Word;
this.FetchWordMEMPTR();
if (condition)
{
this.Call(this.MEMPTR.Word);
this.Call(this.MEMPTR);
}
return condition;
@@ -166,10 +177,10 @@ namespace EightBit
protected bool JumpConditional(bool condition)
{
this.MEMPTR.Word = this.FetchWord().Word;
this.FetchWordMEMPTR();
if (condition)
{
this.Jump(this.MEMPTR.Word);
this.Jump(this.MEMPTR);
}
return condition;
@@ -185,18 +196,39 @@ namespace EightBit
return condition;
}
protected void FetchWordMEMPTR()
{
this.FetchWord();
this.MEMPTR.Low = this.Intermediate.Low;
this.MEMPTR.High = this.Intermediate.High;
}
protected void JumpIndirect()
{
this.FetchWordMEMPTR();
this.Jump(this.MEMPTR);
}
protected void CallIndirect()
{
this.FetchWordMEMPTR();
this.Call(this.MEMPTR);
}
protected void JumpRelative(sbyte offset)
{
this.MEMPTR.Word = (ushort)(this.PC.Word + offset);
this.Jump(this.MEMPTR.Word);
this.Jump(this.MEMPTR);
}
protected bool JumpRelativeConditional(bool condition)
{
var offsetAddress = this.PC.Word++;
this.Intermediate.Low = this.PC.Low;
this.Intermediate.High = this.PC.High;
++this.PC.Word;
if (condition)
{
var offset = (sbyte)this.MemoryRead(offsetAddress);
var offset = (sbyte)this.MemoryRead(this.Intermediate);
this.JumpRelative(offset);
}
@@ -206,7 +238,8 @@ namespace EightBit
protected override sealed void Return()
{
base.Return();
this.MEMPTR.Word = this.PC.Word;
this.MEMPTR.Low = this.PC.Low;
this.MEMPTR.High = this.PC.High;
}
}
}