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Try to minimise use of "Word" from Register16

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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
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31
M6502/M6502Core.cs
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@@ -233,7 +233,7 @@ namespace EightBit
this.Push((byte)(this.P | (source == InterruptSource.hardware ? 0 : (byte)StatusBits.BF)));
}
this.SetFlag(StatusBits.IF); // Disable IRQ
this.Jump(this.GetWordPaged(0xff, vector).Word);
this.Jump(this.GetWordPaged(0xff, vector));
}
#region Interrupt etc. handlers
@@ -341,7 +341,7 @@ namespace EightBit
#region Cycle wastage
protected void SwallowRead() => this.MemoryRead(this.PC.Word);
protected void SwallowRead() => this.MemoryRead(this.PC);
protected void SwallowPop() => this.MemoryRead(this.S, 1);
@@ -408,7 +408,7 @@ namespace EightBit
case 0x48: this.SwallowRead(); this.Push(this.A); break; // PHA (implied)
case 0x49: this.ImmediateRead(); this.EorR(); break; // EOR (immediate)
case 0x4a: this.SwallowRead(); this.A = this.LSR(this.A); break; // LSR A (implied)
case 0x4c: this.AbsoluteAddress(); this.Jump(this.Bus.Address.Word); break; // JMP (absolute)
case 0x4c: this.AbsoluteAddress(); this.Jump(this.Bus.Address); break; // JMP (absolute)
case 0x4d: this.AbsoluteRead(); this.EorR(); break; // EOR (absolute)
case 0x4e: this.AbsoluteRead(); this.ModifyWrite(this.LSR()); break; // LSR (absolute)
@@ -428,7 +428,7 @@ namespace EightBit
case 0x68: this.SwallowRead(); this.SwallowPop(); this.A = this.Through(this.Pop()); break; // PLA (implied)
case 0x69: this.ImmediateRead(); this.ADC(); break; // ADC (immediate)
case 0x6a: this.SwallowRead(); this.A = this.ROR(this.A); break; // ROR A (implied)
case 0x6c: this.IndirectAddress(); this.Jump(this.Bus.Address.Word); break; // JMP (indirect)
case 0x6c: this.IndirectAddress(); this.Jump(this.Bus.Address); break; // JMP (indirect)
case 0x6d: this.AbsoluteRead(); this.ADC(); break; // ADC (absolute)
case 0x6e: this.AbsoluteRead(); this.ModifyWrite(this.ROR()); break; // ROR (absolute)
@@ -718,9 +718,14 @@ namespace EightBit
this.Bus.Address.Low = this.Intermediate.Low;
}
protected void ImmediateAddress() => this.Bus.Address.Word = this.PC.Word++;
protected void ImmediateAddress()
{
this.Bus.Address.Low = this.PC.Low;
this.Bus.Address.High = this.PC.High;
++this.PC.Word;
}
protected void AbsoluteAddress() => this.Bus.Address.Word = this.FetchWord().Word;
protected void AbsoluteAddress() => this.FetchWordAddress();
protected void ZeroPageAddress()
{
@@ -731,13 +736,17 @@ namespace EightBit
protected void ZeroPageIndirectAddress()
{
this.ZeroPageAddress();
this.Bus.Address.Word = this.GetWordPaged().Word;
this.GetWordPaged();
this.Bus.Address.Low = this.Intermediate.Low;
this.Bus.Address.High = this.Intermediate.High;
}
protected void IndirectAddress()
{
this.AbsoluteAddress();
this.Bus.Address.Word = this.GetWordPaged().Word;
this.GetWordPaged();
this.Bus.Address.Low = this.Intermediate.Low;
this.Bus.Address.High = this.Intermediate.High;
}
protected void ZeroPageWithIndexAddress(byte index)
@@ -763,7 +772,9 @@ namespace EightBit
protected void IndexedIndirectXAddress()
{
this.ZeroPageXAddress();
this.Bus.Address.Word = this.GetWordPaged().Word;
this.GetWordPaged();
this.Bus.Address.Low = this.Intermediate.Low;
this.Bus.Address.High = this.Intermediate.High;
}
protected void IndirectIndexedYAddress()
@@ -849,7 +860,7 @@ namespace EightBit
this.SwallowRead();
this.NoteFixedAddress(this.PC.Word + relative);
this.MaybeFixup();
this.Jump(this.Bus.Address.Word);
this.Jump(this.Bus.Address);
}
}