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Some simplifications

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Adrian Conlon committed 2026-04-07 12:02:31 +01:00
1 parent 284158247b
commit 53e33b9eef
4 files changed
+31 -62
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EightBit/Processor.cs
+2 -29
View File
@@ -163,37 +163,16 @@ namespace EightBit
protected void OnWrittenMemory() => this.WrittenMemory?.Invoke(this, EventArgs.Empty);
protected void MemoryWrite(byte low, byte high)
{
this.Bus.Address.Assign(low, high);
this.MemoryWrite();
}
protected void MemoryWrite(byte low, byte high, byte data)
{
this.Bus.Address.Assign(low, high);
this.Bus.Data = data;
this.MemoryWrite();
}
protected void MemoryWrite(ushort address, byte data)
{
this.Bus.Address.Word = address;
this.Bus.Data = data;
this.MemoryWrite();
this.MemoryWrite(data);
}
protected void MemoryWrite(Register16 address, byte data)
{
this.Bus.Address.Assign(address);
this.Bus.Data = data;
this.MemoryWrite();
}
protected void MemoryWrite(Register16 address)
{
this.Bus.Address.Assign(address);
this.MemoryWrite();
this.MemoryWrite(data);
}
protected void MemoryWrite(byte data)
@@ -212,12 +191,6 @@ namespace EightBit
return this.MemoryRead();
}
protected byte MemoryRead(ushort address)
{
this.Bus.Address.Word = address;
return this.MemoryRead();
}
protected byte MemoryRead(Register16 address)
{
this.Bus.Address.Assign(address);
Intel8080/Intel8080.cs
+5 -13
View File
@@ -628,7 +628,7 @@ namespace Intel8080
private byte Increment(byte operand)
{
var result = ++operand;
var result = operand; ++result;
AdjustSZP(result);
ClearBit(StatusBits.AC, LowNibble(result));
return result;
@@ -636,7 +636,7 @@ namespace Intel8080
private byte Decrement(byte operand)
{
var result = --operand;
var result = operand; --result;
AdjustSZP(result);
SetBit(StatusBits.AC, LowNibble(result) != (byte)Mask.Four);
return result;
@@ -657,12 +657,8 @@ namespace Intel8080
protected sealed override void CallConditional(bool condition)
{
this.FetchInto(this.MEMPTR);
if (condition)
{
this.Call();
}
else
base.CallConditional(condition);
if (!condition)
{
this.Tick();
}
@@ -670,12 +666,8 @@ namespace Intel8080
protected sealed override void ReturnConditionalFlag(int flag)
{
var condition = this.ConvertCondition(flag);
this.Tick();
if (condition)
{
this.Return();
}
base.ReturnConditionalFlag(flag);
}
private Register16 Add(Register16 operand, Register16 value)
LR35902/LR35902.cs
+14 -8
View File
@@ -5,6 +5,7 @@
namespace LR35902
{
using EightBit;
using System.Diagnostics;
public sealed class LR35902 : IntelProcessor
{
@@ -336,29 +337,34 @@ namespace LR35902
private void Start() => this.Stopped = false;
private void MemoryUpdate(int ticks)
private void MemoryUpdate(int ticks = 1)
{
Debug.Assert(ticks > 0, "Ticks must be greater than zero");
this.OnWritingMemory();
this.LowerMWR();
this.LowerWR();
base.MemoryWrite();
this.TickMachine(ticks);
this.RaiseWR();
this.RaiseMWR();
this.OnWrittenMemory();
}
protected override void MemoryWrite()
{
this.MemoryUpdate(1);
this.MemoryUpdate();
}
protected override byte MemoryRead()
{
this.OnReadingMemory();
this.LowerMWR();
this.LowerRD();
_ = base.MemoryRead();
this.TickMachine();
this.RaiseRD();
this.RaiseMWR();
this.OnReadMemory();
return this.Bus.Data;
}
@@ -863,7 +869,7 @@ namespace LR35902
break;
case 1: // CB prefix
this._prefixCB = true;
this.Execute(this.FetchByte());
this.Execute(this.FetchInstruction());
break;
case 6: // DI
this.DisableInterrupts();
@@ -1063,9 +1069,9 @@ namespace LR35902
private byte RL(byte operand)
{
this.F = ClearBit(this.F, StatusBits.NF | StatusBits.HC | StatusBits.ZF);
this.ClearBit(StatusBits.NF | StatusBits.HC | StatusBits.ZF);
var carry = this.Carry();
this.F = SetBit(this.F, StatusBits.CF, operand & (byte)Bits.Bit7);
this.SetBit(StatusBits.CF, operand & (byte)Bits.Bit7);
return (byte)((operand << 1) | (carry >> 4)); // CF at Bit4
}
@@ -1146,13 +1152,13 @@ namespace LR35902
this.SetBit(StatusBits.CF, this.Carry() != 0 || (updated & (int)Bits.Bit8) != 0);
this.A = LowByte(updated);
this.F = AdjustZero(this.F, this.A);
this.AdjustZero(this.A);
}
protected override void CPL()
{
base.CPL();
this.F = SetBit(this.F, StatusBits.HC | StatusBits.NF);
this.SetBit(StatusBits.HC | StatusBits.NF);
}
private void SCF()
@@ -1164,7 +1170,7 @@ namespace LR35902
private void CCF()
{
this.ClearBit(StatusBits.NF | StatusBits.HC);
this.ClearBit(StatusBits.CF, this.F & (byte)StatusBits.CF);
this.ClearBit(StatusBits.CF, this.Carry());
}
private void RetI()
Z80/Z80.cs
+10 -12
View File
@@ -1643,19 +1643,21 @@ namespace Z80
private byte Increment(byte operand)
{
this.ClearBit(StatusBits.NF);
this.AdjustSZXY(++operand);
this.SetBit(StatusBits.VF, operand == (byte)Bits.Bit7);
this.ClearBit(StatusBits.HC, LowNibble(operand));
return operand;
var result = operand; ++result;
this.AdjustSZXY(result);
this.SetBit(StatusBits.VF, result == (byte)Bits.Bit7);
this.ClearBit(StatusBits.HC, LowNibble(result));
return result;
}
private byte Decrement(byte operand)
{
this.SetBit(StatusBits.NF);
this.ClearBit(StatusBits.HC, LowNibble(operand));
this.AdjustSZXY(--operand);
this.SetBit(StatusBits.VF, operand == (byte)Mask.Seven);
return operand;
var result = operand; --result;
this.AdjustSZXY(result);
this.SetBit(StatusBits.VF, result == (byte)Mask.Seven);
return result;
}
private void RetN()
@@ -1681,12 +1683,8 @@ namespace Z80
protected sealed override void ReturnConditionalFlag(int flag)
{
var condition = this.ConvertCondition(flag);
this.Tick();
if (condition)
{
this.Return();
}
base.ReturnConditionalFlag(flag);
}
private Register16 SBC(Register16 operand, Register16 value)