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Correct all obvious timing inaccuracies

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This commit is contained in:
Adrian Conlon committed 2026-05-09 17:15:11 +01:00
1 parent a9f2049c17
commit 1c485bca22
1 file changed
+107 -34
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MC6809/MC6809.cs
+107 -34
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@@ -627,7 +627,11 @@ namespace MC6809
this.SwallowRead();
}
private void ExtendedAddress() => this.FetchWord();
private void ExtendedAddress()
{
this.FetchWord();
this.SwallowRead();
}
private Register16 RR(int which)
{
@@ -775,9 +779,7 @@ namespace MC6809
private void ExtendedWord()
{
this.ExtendedAddress();
this.SwallowRead();
this.GetWord(this.Intermediate);
this.SwallowRead();
}
#endregion
@@ -831,12 +833,14 @@ namespace MC6809
private void LBSR()
{
this.RelativeWordAddress();
this.SwallowRead(4);
this.Call(this.Intermediate);
}
private void BSR()
{
this.RelativeByteAddress();
this.SwallowRead(3);
this.Call(this.Intermediate);
}
@@ -884,6 +888,7 @@ namespace MC6809
private void BranchLong(bool condition)
{
this.RelativeWordAddress();
this.SwallowRead();
if (this.Branch(this.Intermediate, condition))
{
this.SwallowRead();
@@ -925,9 +930,10 @@ namespace MC6809
private void PSH(Register16 stack)
{
var control = this.Bus.Data;
this.SwallowRead(2);
this.SwallowPop(stack);
this.PSH(stack, this.Bus.Data);
this.PSH(stack, control);
}
private void PSH(Register16 stack, byte control)
@@ -985,8 +991,9 @@ namespace MC6809
private void PUL(Register16 stack)
{
var control = this.Bus.Data;
this.SwallowRead(2);
this.PUL(stack, this.Bus.Data);
this.PUL(stack, control);
this.SwallowPop(stack);
}
@@ -1349,7 +1356,7 @@ namespace MC6809
case 0x73: this.ExtendedByte(); this.COM(); Debug.Assert(this.Cycles == 7); break; // COM (extended)
// CWAI
case 0x3c: this.CWAI(); break; // CWAI (inherent) - cycles omitted: halts before full interrupt response
case 0x3c: this.CWAI(); break; // CWAI (inherent) - cycles omitted: halts before full interrupt response
// DAA
case 0x19: this.DAA(); Debug.Assert(this.Cycles == 2); break; // DAA (inherent)
@@ -1441,7 +1448,7 @@ namespace MC6809
case 0x74: this.ExtendedByte(); this.LSR(); Debug.Assert(this.Cycles == 7); break; // LSR (extended)
// MUL
case 0x3d: this.MUL(); Debug.Assert(this.Cycles == 11); break; // MUL (inherent)
case 0x3d: this.MUL(); Debug.Assert(this.Cycles == 11); break; // MUL (inherent)
// NEG
case 0x00: this.DirectByte(); this.NEG(); Debug.Assert(this.Cycles == 6); break; // NEG (direct)
@@ -1451,7 +1458,7 @@ namespace MC6809
case 0x70: this.ExtendedByte(); this.NEG(); Debug.Assert(this.Cycles == 7); break; // NEG (extended)
// NOP
case 0x12: this.NOP(); Debug.Assert(this.Cycles == 2); break; // NOP (inherent)
case 0x12: this.NOP(); Debug.Assert(this.Cycles == 2); break; // NOP (inherent)
// OR
@@ -1493,27 +1500,27 @@ namespace MC6809
case 0x76: this.ExtendedByte(); this.ROR(); Debug.Assert(this.Cycles == 7); break; // ROR (extended)
// RTI
case 0x3B: this.RTI(); Debug.Assert(this.Cycles == (this.E ? 15 : 6)); break; // RTI (inherent)
case 0x3B: this.RTI(); Debug.Assert(this.Cycles == (this.E ? 15 : 6)); break; // RTI (inherent)
// RTS
case 0x39: this.RTS(); Debug.Assert(this.Cycles == 5); break; // RTS (inherent)
case 0x39: this.RTS(); Debug.Assert(this.Cycles == 5); break; // RTS (inherent)
// SBC
// SBCA
case 0x82: this.ImmediateByte(); this.SBCA(); Debug.Assert(this.Cycles == 2); break; // SBC (SBCA immediate)
case 0x92: this.DirectByte(); this.SBCA(); Debug.Assert(this.Cycles == 4); break; // SBC (SBCA direct)
case 0xa2: this.IndexedByte(); this.SBCA(); Debug.Assert(this.Cycles >= 4); break; // SBC (SBCA indexed)
case 0xb2: this.ExtendedByte(); this.SBCA(); Debug.Assert(this.Cycles == 5); break; // SBC (SBCB extended)
case 0x82: this.ImmediateByte(); this.SBCA(); Debug.Assert(this.Cycles == 2); break; // SBC (SBCA immediate)
case 0x92: this.DirectByte(); this.SBCA(); Debug.Assert(this.Cycles == 4); break; // SBC (SBCA direct)
case 0xa2: this.IndexedByte(); this.SBCA(); Debug.Assert(this.Cycles >= 4); break; // SBC (SBCA indexed)
case 0xb2: this.ExtendedByte(); this.SBCA(); Debug.Assert(this.Cycles == 5); break; // SBC (SBCB extended)
// SBCB
case 0xc2: this.ImmediateByte(); this.SBCB(); Debug.Assert(this.Cycles == 2); break; // SBC (SBCB immediate)
case 0xd2: this.DirectByte(); this.SBCB(); Debug.Assert(this.Cycles == 4); break; // SBC (SBCB direct)
case 0xe2: this.IndexedByte(); this.SBCB(); Debug.Assert(this.Cycles >= 4); break; // SBC (SBCB indexed)
case 0xf2: this.ExtendedByte(); this.SBCB(); Debug.Assert(this.Cycles == 5); break; // SBC (SBCB extended)
case 0xc2: this.ImmediateByte(); this.SBCB(); Debug.Assert(this.Cycles == 2); break; // SBC (SBCB immediate)
case 0xd2: this.DirectByte(); this.SBCB(); Debug.Assert(this.Cycles == 4); break; // SBC (SBCB direct)
case 0xe2: this.IndexedByte(); this.SBCB(); Debug.Assert(this.Cycles >= 4); break; // SBC (SBCB indexed)
case 0xf2: this.ExtendedByte(); this.SBCB(); Debug.Assert(this.Cycles == 5); break; // SBC (SBCB extended)
// SEX
case 0x1d: this.SEX(); Debug.Assert(this.Cycles == 2); break; // SEX (inherent)
case 0x1d: this.SEX(); Debug.Assert(this.Cycles == 2); break; // SEX (inherent)
// ST
@@ -1569,7 +1576,7 @@ namespace MC6809
case 0x13: this.SYNC(); Debug.Assert(this.Cycles == 2); break; // SYNC (inherent)
// TFR
case 0x1f: this.ImmediateByte(); this.TFR(); Debug.Assert(this.Cycles == 6); break; // TFR (immediate)
case 0x1f: this.ImmediateByte(); this.TFR(); Debug.Assert(this.Cycles == 6); break; // TFR (immediate)
// TST
case 0x0d: this.DirectByte(); this.TST(); Debug.Assert(this.Cycles == 6); break; // TST (direct)
@@ -1731,7 +1738,11 @@ namespace MC6809
this.SwallowRead();
}
private void ANDCC() => this.CC &= this.Bus.Data;
private void ANDCC()
{
this.CC &= this.Bus.Data;
this.SwallowRead();
}
private void ANDA() => this.A = this.And(this.A, this.Bus.Data);
private void ANDB() => this.B = this.And(this.B, this.Bus.Data);
@@ -1750,7 +1761,12 @@ namespace MC6809
this.B = this.ArithmeticShiftLeft(this.B);
}
private void ASL() => this.MemoryWrite(this.ArithmeticShiftLeft(this.Bus.Data));
private void ASL()
{
var result = this.ArithmeticShiftLeft(this.Bus.Data);
this.SwallowEffectiveAddress();
this.MemoryWrite(result);
}
private byte ArithmeticShiftLeft(byte operand)
{
@@ -1773,7 +1789,12 @@ namespace MC6809
this.B = this.ArithmeticShiftRight(this.B);
}
private void ASR() => this.MemoryWrite(this.ArithmeticShiftRight(this.Bus.Data));
private void ASR()
{
var result = this.ArithmeticShiftRight(this.Bus.Data);
this.SwallowEffectiveAddress();
this.MemoryWrite(result);
}
private byte ArithmeticShiftRight(byte operand)
{
@@ -1800,7 +1821,13 @@ namespace MC6809
this.B = this.Clear();
}
private void CLR() => this.MemoryWrite(this.Intermediate, this.Clear());
private void CLR()
{
this.SwallowEffectiveAddress();
var result = this.Clear();
this.SwallowEffectiveAddress();
this.MemoryWrite(this.Intermediate, result);
}
private byte Clear()
{
@@ -1833,7 +1860,12 @@ namespace MC6809
this.B = this.Complement(this.B);
}
private void COM() => this.MemoryWrite(this.Complement(this.Bus.Data));
private void COM()
{
var result = this.Complement(this.Bus.Data);
this.SwallowEffectiveAddress();
this.MemoryWrite(result);
}
private byte Complement(byte operand)
{
@@ -1897,7 +1929,12 @@ namespace MC6809
this.B = this.Decrement(this.B);
}
private void DEC() => this.MemoryWrite(this.Decrement(this.Bus.Data));
private void DEC()
{
var result = this.Decrement(this.Bus.Data);
this.SwallowEffectiveAddress();
this.MemoryWrite(result);
}
private byte Decrement(byte operand)
{
@@ -1920,7 +1957,12 @@ namespace MC6809
this.B = this.Increment(this.B);
}
private void INC() => this.MemoryWrite(this.Increment(this.Bus.Data));
private void INC()
{
var result = this.Increment(this.Bus.Data);
this.SwallowEffectiveAddress();
this.MemoryWrite(result);
}
private byte Increment(byte operand)
{
@@ -1953,7 +1995,12 @@ namespace MC6809
this.B = this.LogicalShiftRight(this.B);
}
private void LSR() => this.MemoryWrite(this.LogicalShiftRight(this.Bus.Data));
private void LSR()
{
var result = this.LogicalShiftRight(this.Bus.Data);
this.SwallowEffectiveAddress();
this.MemoryWrite(result);
}
private byte LogicalShiftRight(byte operand)
{
@@ -1983,7 +2030,12 @@ namespace MC6809
this.B = this.Negate(this.B);
}
private void NEG() => this.MemoryWrite(this.Negate(this.Bus.Data));
private void NEG()
{
var result = this.Negate(this.Bus.Data);
this.SwallowEffectiveAddress();
this.MemoryWrite(result);
}
private byte Negate(byte operand)
{
@@ -1995,7 +2047,11 @@ namespace MC6809
return operand;
}
private void ORCC() => this.CC |= this.Bus.Data;
private void ORCC()
{
this.SwallowCurrent();
this.CC |= this.Bus.Data;
}
private void ORA() => this.A = this.Or(this.A);
private void ORB() => this.B = this.Or(this.B);
@@ -2014,7 +2070,12 @@ namespace MC6809
this.B = this.RotateLeft(this.B);
}
private void ROL() => this.MemoryWrite(this.RotateLeft(this.Bus.Data));
private void ROL()
{
var result = this.RotateLeft(this.Bus.Data);
this.SwallowEffectiveAddress();
this.MemoryWrite(result);
}
private byte RotateLeft(byte operand)
{
@@ -2038,7 +2099,12 @@ namespace MC6809
this.B = this.RotateRight(this.B);
}
private void ROR() => this.MemoryWrite(this.RotateRight(this.Bus.Data));
private void ROR()
{
var result = this.RotateRight(this.Bus.Data);
this.SwallowEffectiveAddress();
this.MemoryWrite(result);
}
private byte RotateRight(byte operand)
{
@@ -2051,6 +2117,7 @@ namespace MC6809
private void RTI()
{
this.SwallowCurrent();
this.RestoreRegisterState();
this.SwallowRead();
}
@@ -2086,6 +2153,7 @@ namespace MC6809
var subtraction = operand.Word - data.Word;
this.CC = this.AdjustSubtraction(operand, data, (uint)subtraction);
result.Word = (ushort)subtraction;
this.SwallowRead();
}
private void SEX()
@@ -2110,7 +2178,7 @@ namespace MC6809
SwallowRead();
this.GetWordPaged(0xff, SWI_vector);
this.Jump(this.Intermediate);
SwallowRead();
this.SwallowRead();
}
private void SWI2()
@@ -2147,7 +2215,12 @@ namespace MC6809
this.Test(this.B);
}
private void TST() => this.Test(this.Bus.Data);
private void TST()
{
this.Test(this.Bus.Data);
this.SwallowRead();
this.SwallowRead();
}
private void Test(byte data) => this.Compare(data, 0);