Turns out using lambdas to control pins is lovely and correct, but terribly slow. Back to a more traditional method.

EightBit/BigEndianProcessor.cs

@@ -14,7 +14,6 @@ namespace EightBit
 
         public override void PokeWord(ushort address, Register16 value)
         {
-            ArgumentNullException.ThrowIfNull(value);
             this.Bus.Poke(address, value.High);
             this.Bus.Poke(++address, value.Low);
         }
@@ -51,14 +50,12 @@ namespace EightBit
 
         protected override void PushWord(Register16 value)
         {
-            ArgumentNullException.ThrowIfNull(value);
             this.Push(value.Low);
             this.Push(value.High);
         }
 
         protected override void SetWord(Register16 value)
         {
-            ArgumentNullException.ThrowIfNull(value);
             this.MemoryWrite(value.High);
             ++this.Bus.Address.Word;
             this.MemoryWrite(value.Low);
@@ -66,7 +63,6 @@ namespace EightBit
 
         protected override void SetWordPaged(Register16 value)
         {
-            ArgumentNullException.ThrowIfNull(value);
             this.MemoryWrite(value.High);
             ++this.Bus.Address.Low;
             this.MemoryWrite(value.Low);

EightBit/Bus.cs

@@ -28,7 +28,6 @@ namespace EightBit
 
         public byte Peek(Register16 absolute)
         {
-            ArgumentNullException.ThrowIfNull(absolute);
             return this.Peek(absolute.Word);
         }
 
@@ -38,7 +37,6 @@ namespace EightBit
 
         public void Poke(Register16 absolute, byte value)
         {
-            ArgumentNullException.ThrowIfNull(absolute);
             this.Poke(absolute.Word, value);
         }
 
@@ -58,7 +56,6 @@ namespace EightBit
 
         public byte Read(Register16 absolute)
         {
-            ArgumentNullException.ThrowIfNull(absolute);
             return this.Read(absolute.Low, absolute.High);
         }
 
@@ -89,7 +86,6 @@ namespace EightBit
 
         public void Write(Register16 absolute, byte value)
         {
-            ArgumentNullException.ThrowIfNull(absolute);
             this.Write(absolute.Low, absolute.High, value);
         }
 
@@ -133,7 +129,6 @@ namespace EightBit
 
         protected ref byte Reference(Register16 absolute)
         {
-            ArgumentNullException.ThrowIfNull(absolute);
             return ref this.Reference(absolute.Word);
         }
 

EightBit/Device.cs

@@ -25,9 +25,9 @@ namespace EightBit
         {
             if (this.POWER.Lowered())
             {
-                this.OnRaisingPOWER();
+                RaisingPOWER?.Invoke(this, EventArgs.Empty);
                 this.POWER.Raise();
-                this.OnRaisedPOWER();
+                RaisedPOWER?.Invoke(this, EventArgs.Empty);
             }
         }
 
@@ -35,18 +35,10 @@ namespace EightBit
         {
             if (this.POWER.Raised())
             {
-                this.OnLoweringPOWER();
+                LoweringPOWER?.Invoke(this, EventArgs.Empty);
                 this.POWER.Lower();
-                this.OnLoweredPOWER();
+                LoweredPOWER?.Invoke(this, EventArgs.Empty);
             }
         }
-
-        protected virtual void OnRaisingPOWER() => RaisingPOWER?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisedPOWER() => RaisedPOWER?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnLoweringPOWER() => LoweringPOWER?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnLoweredPOWER() => LoweredPOWER?.Invoke(this, EventArgs.Empty);
     }
 }

EightBit/EightBit.csproj

@@ -7,7 +7,7 @@
     <GenerateDocumentationFile>False</GenerateDocumentationFile>
     <SignAssembly>False</SignAssembly>
     <EnforceCodeStyleInBuild>True</EnforceCodeStyleInBuild>
-    <AnalysisLevel>latest-all</AnalysisLevel>
+    <AnalysisLevel>latest-recommended</AnalysisLevel>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">

EightBit/IntelProcessor.cs

@@ -20,6 +20,7 @@ namespace EightBit
             {
                 this._decodedOpCodes[i] = new((byte)i);
             }
+            this.RaisedPOWER += this.IntelProcessor_RaisedPOWER;
         }
 
         public event EventHandler<EventArgs>? RaisingHALT;
@@ -67,9 +68,10 @@ namespace EightBit
         {
             if (this.HALT.Lowered())
             {
-                this.OnRaisingHALT();
+                RaisingHALT?.Invoke(this, EventArgs.Empty);
                 this.HALT.Raise();
-                this.OnRaisedHALT();
+                ++this.PC.Word; // Release the PC from HALT instruction
+                RaisedHALT?.Invoke(this, EventArgs.Empty);
             }
         }
 
@@ -77,9 +79,10 @@ namespace EightBit
         {
             if (this.HALT.Raised())
             {
-                this.OnLoweringHALT();
+                LoweringHALT?.Invoke(this, EventArgs.Empty);
                 this.HALT.Lower();
-                this.OnLoweredHALT();
+                --this.PC.Word; // Keep the PC on the HALT instruction (i.e. executing NOP)
+                LoweredHALT?.Invoke(this, EventArgs.Empty);
             }
         }
 
@@ -102,27 +105,10 @@ namespace EightBit
             return HalfCarryTableSub[index & (int)Mask.Three];
         }
 
-        protected override void OnRaisedPOWER()
+        private void IntelProcessor_RaisedPOWER(object? sender, EventArgs e)
         {
             this.PC.Word = this.SP.Word = this.AF.Word = this.BC.Word = this.DE.Word = this.HL.Word = (ushort)Mask.Sixteen;
             this.RaiseHALT();
-            base.OnRaisedPOWER();
-        }
-
-        protected virtual void OnRaisingHALT() => RaisingHALT?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisedHALT()
-        {
-            ++this.PC.Word; // Release the PC from HALT instruction
-            RaisedHALT?.Invoke(this, EventArgs.Empty);
-        }
-
-        protected virtual void OnLoweringHALT() => LoweringHALT?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnLoweredHALT()
-        {
-            --this.PC.Word; // Keep the PC on the HALT instruction (i.e. executing NOP)
-            LoweredHALT?.Invoke(this, EventArgs.Empty);
         }
 
         protected override void HandleRESET()

EightBit/LittleEndianProcessor.cs

@@ -15,7 +15,6 @@ namespace EightBit
 
         public override void PokeWord(ushort address, Register16 value)
         {
-            ArgumentNullException.ThrowIfNull(value);
             this.Bus.Poke(address, value.Low);
             this.Bus.Poke(++address, value.High);
         }
@@ -52,14 +51,12 @@ namespace EightBit
 
         protected override void PushWord(Register16 value)
         {
-            ArgumentNullException.ThrowIfNull(value);
             this.Push(value.High);
             this.Push(value.Low);
         }
 
         protected override void SetWord(Register16 value)
         {
-            ArgumentNullException.ThrowIfNull(value);
             this.MemoryWrite(value.Low);
             ++this.Bus.Address.Word;
             this.MemoryWrite(value.High);
@@ -67,7 +64,6 @@ namespace EightBit
 
         protected override void SetWordPaged(Register16 value)
         {
-            ArgumentNullException.ThrowIfNull(value);
             this.MemoryWrite(value.Low);
             ++this.Bus.Address.Low;
             this.MemoryWrite(value.High);

EightBit/Processor.cs

@@ -10,57 +10,9 @@ namespace EightBit
 
         public event EventHandler<EventArgs>? ExecutingInstruction;
         public event EventHandler<EventArgs>? ExecutedInstruction;
-        protected virtual void OnExecutedInstruction() => ExecutedInstruction?.Invoke(this, EventArgs.Empty);
-        protected virtual void OnExecutingInstruction() => ExecutingInstruction?.Invoke(this, EventArgs.Empty);
 
         #endregion
 
-        #region Bus events
-
-        #region Memory events
-
-        #region Memory read events
-
-        public event EventHandler<EventArgs>? ReadingMemory;
-        public event EventHandler<EventArgs>? ReadMemory;
-        protected virtual void OnReadingMemory() => ReadingMemory?.Invoke(this, EventArgs.Empty);
-        protected virtual void OnReadMemory() => ReadMemory?.Invoke(this, EventArgs.Empty);
-
-        #endregion
-
-        #region Memory write events
-
-        public event EventHandler<EventArgs>? WritingMemory;
-        public event EventHandler<EventArgs>? WrittenMemory;
-        protected virtual void OnWritingMemory() => WritingMemory?.Invoke(this, EventArgs.Empty);
-        protected virtual void OnWrittenMemory() => WrittenMemory?.Invoke(this, EventArgs.Empty);
-
-        #endregion
-
-        #endregion
-
-        #region IO events
-
-        #region IO read events
-
-        public event EventHandler<EventArgs>? ReadingIO;
-        public event EventHandler<EventArgs>? ReadIO;
-        protected virtual void OnReadingIO() => ReadingIO?.Invoke(this, EventArgs.Empty);
-        protected virtual void OnReadIO() => ReadIO?.Invoke(this, EventArgs.Empty);
-
-        #endregion
-
-        #region IO write events
-
-        public event EventHandler<EventArgs>? WritingIO;
-        public event EventHandler<EventArgs>? WrittenIO;
-        protected virtual void OnWritingIO() => WritingIO?.Invoke(this, EventArgs.Empty);
-        protected virtual void OnWrittenIO() => WrittenIO?.Invoke(this, EventArgs.Empty);
-        #endregion
-
-        #endregion
-
-        #endregion
 
         private PinLevel _resetLine;
         private PinLevel _intLine;
@@ -108,12 +60,12 @@ namespace EightBit
         public virtual int Step()
         {
             this.ResetCycles();
-            this.OnExecutingInstruction();
+            ExecutingInstruction?.Invoke(this, EventArgs.Empty);
             if (this.Powered)
             {
                 this.PoweredStep();
             }
-            this.OnExecutedInstruction();
+            ExecutedInstruction?.Invoke(this, EventArgs.Empty);
             return this.Cycles;
         }
 
@@ -149,9 +101,9 @@ namespace EightBit
         {
             if (this.RESET.Lowered())
             {
-                this.OnRaisingRESET();
+                RaisingRESET?.Invoke(this, EventArgs.Empty);
                 this.RESET.Raise();
-                this.OnRaisedRESET();
+                RaisedRESET?.Invoke(this, EventArgs.Empty);
             }
         }
 
@@ -159,9 +111,9 @@ namespace EightBit
         {
             if (this.RESET.Raised())
             {
-                this.OnLoweringRESET();
+                LoweringRESET?.Invoke(this, EventArgs.Empty);
                 this.RESET.Lower();
-                this.OnLoweredRESET();
+                LoweredRESET?.Invoke(this, EventArgs.Empty);
             }
         }
 
@@ -170,9 +122,9 @@ namespace EightBit
         {
             if (this.INT.Lowered())
             {
-                this.OnRaisingINT();
+                RaisingINT?.Invoke(this, EventArgs.Empty);
                 this.INT.Raise();
-                this.OnRaisedINT();
+                RaisedINT?.Invoke(this, EventArgs.Empty);
             }
         }
 
@@ -180,9 +132,9 @@ namespace EightBit
         {
             if (this.INT.Raised())
             {
-                this.OnLoweringINT();
+                LoweringINT?.Invoke(this, EventArgs.Empty);
                 this.INT.Lower();
-                this.OnLoweredINT();
+                LoweredINT?.Invoke(this, EventArgs.Empty);
             }
         }
 
@@ -226,13 +178,11 @@ namespace EightBit
 
         protected void MemoryWrite(Register16 address, byte data)
         {
-            ArgumentNullException.ThrowIfNull(address);
             this.MemoryWrite(address.Low, address.High, data);
         }
 
         protected void MemoryWrite(Register16 address)
         {
-            ArgumentNullException.ThrowIfNull(address);
             this.MemoryWrite(address.Low, address.High);
         }
 
@@ -260,7 +210,6 @@ namespace EightBit
 
         protected byte MemoryRead(Register16 address)
         {
-            ArgumentNullException.ThrowIfNull(address);
             return this.MemoryRead(address.Low, address.High);
         }
 
@@ -286,7 +235,6 @@ namespace EightBit
 
         protected Register16 GetWordPaged(Register16 address)
         {
-            ArgumentNullException.ThrowIfNull(address);
             return this.GetWordPaged(address.High, address.Low);
         }
 
@@ -300,7 +248,6 @@ namespace EightBit
 
         protected void SetWordPaged(Register16 address, Register16 value)
         {
-            ArgumentNullException.ThrowIfNull(address);
             this.SetWordPaged(address.High, address.Low, value);
         }
 
@@ -354,7 +301,6 @@ namespace EightBit
 
         protected void Jump(Register16 destination)
         {
-            ArgumentNullException.ThrowIfNull(destination);
             this.PC.Assign(destination);
         }
 

EightBit/Register16.cs

@@ -46,7 +46,6 @@ namespace EightBit
 
         public Register16(Register16 rhs)
         {
-            ArgumentNullException.ThrowIfNull(rhs);
             this.Low = rhs.Low;
             this.High = rhs.High;
         }
@@ -68,7 +67,6 @@ namespace EightBit
 
         public static bool operator ==(Register16 left, Register16 right)
         {
-            ArgumentNullException.ThrowIfNull(left);
             return left.Equals(right);
         }
 
@@ -88,7 +86,6 @@ namespace EightBit
 
         public void Assign(Register16 from)
         {
-            ArgumentNullException.ThrowIfNull(from);
             this.Assign(from._low, from._high);
         }
     }

M6502/Core.cs

@@ -8,8 +8,14 @@ namespace M6502
 {
     using EightBit;
 
-    public abstract class Core(Bus bus) : LittleEndianProcessor(bus)
+    public abstract class Core : LittleEndianProcessor
     {
+        protected Core(Bus bus)
+        : base(bus)
+        {
+            this.RaisedPOWER += this.Core_RaisedPOWER;
+        }
+
         #region Pin controls
 
         #region NMI pin
@@ -104,16 +110,22 @@ namespace M6502
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1030:Use events where appropriate", Justification = "The word 'raise' is used in an electrical sense")]
         protected virtual void RaiseSYNC()
         {
-            this.OnRaisingSYNC();
+            if (this.SYNC.Lowered())
-            this.SYNC.Raise();
+            {
-            this.OnRaisedSYNC();
+                RaisingSYNC?.Invoke(this, EventArgs.Empty);
+                this.SYNC.Raise();
+                RaisedSYNC?.Invoke(this, EventArgs.Empty);
+            }
         }
 
         protected virtual void LowerSYNC()
         {
-            this.OnLoweringSYNC();
+            if (this.SYNC.Raised())
-            this.SYNC.Lower();
+            {
-            this.OnLoweredSYNC();
+                LoweringSYNC?.Invoke(this, EventArgs.Empty);
+                this.SYNC.Lower();
+                LoweredSYNC?.Invoke(this, EventArgs.Empty);
+            }
         }
 
         #endregion
@@ -190,7 +202,7 @@ namespace M6502
 
         #endregion
 
-        protected override void OnRaisedPOWER()
+        private void Core_RaisedPOWER(object? sender, EventArgs e)
         {
             this.X = (byte)Bits.Bit7;
             this.Y = 0;
@@ -199,7 +211,6 @@ namespace M6502
             this.S = (byte)Mask.Eight;
             this.LowerSYNC();
             this.LowerRW();
-            base.OnRaisedPOWER();
         }
 
         #endregion
@@ -551,9 +562,7 @@ namespace M6502
 
         private void FetchInstruction()
         {
-            // Instruction fetch beginning
             this.LowerSYNC();
-
             System.Diagnostics.Debug.Assert(this.Cycles == 1, "An extra cycle has occurred");
 
             // Can't use fetchByte, since that would add an extra tick.
@@ -561,8 +570,6 @@ namespace M6502
             this.OpCode = this.ReadFromBus();
 
             System.Diagnostics.Debug.Assert(this.Cycles == 1, "BUS read has introduced stray cycles");
-
-            // Instruction fetch has now completed
             this.RaiseSYNC();
         }
 

M6502/M6502.HarteTest/Checker.cs

@@ -282,13 +282,9 @@
             }
         }
 
-        private void Runner_ReadByte(object? sender, EventArgs e) => this.AddActualReadCycle(this.Runner.Address, this.Runner.Data);
+        private void Runner_ReadByte(object? sender, EventArgs e) => this.AddActualCycle(this.Runner.Address, this.Runner.Data, "read");
 
-        private void Runner_WrittenByte(object? sender, EventArgs e) => this.AddActualWriteCycle(this.Runner.Address, this.Runner.Data);
+        private void Runner_WrittenByte(object? sender, EventArgs e) => this.AddActualCycle(this.Runner.Address, this.Runner.Data, "write");
-
-        private void AddActualReadCycle(EightBit.Register16 address, byte value) => this.AddActualCycle(address, value, "read");
-
-        private void AddActualWriteCycle(EightBit.Register16 address, byte value) => this.AddActualCycle(address, value, "write");
 
         private void AddActualCycle(EightBit.Register16 address, byte value, string action) => this.AddActualCycle(address.Word, value, action);
 

Z80/Z80.FuseTest/TestRunner.cs

@@ -98,21 +98,30 @@ namespace Z80.FuseTest
 
         public override void Initialize()
         {
+            this.ReadByte += this.Event_ReadByte;
+            this.WrittenByte += this.Event_WrittenByte;
             this.ports.ReadPort += this.Ports_ReadPort;
             this.ports.WrittenPort += this.Ports_WrittenPort;
             this.cpu.ExecutedInstruction += this.Cpu_ExecutedInstruction;
         }
 
-        protected override void OnReadByte()
+        private void Ports_ReadPort(object? sender, EventArgs e) => this.AddActualEvent("PR");
-        {
+        private void Ports_WrittenPort(object? sender, EventArgs e) => this.AddActualEvent("PW");
-            this.actualEvents.Add(new TestEvent(this.totalCycles + this.cpu.Cycles, "MR", this.Address.Word, this.Data));
+        private void Event_ReadByte(object? sender, EventArgs e) => this.AddActualEvent("MR");
-            base.OnReadByte();
+        private void Event_WrittenByte(object? sender, EventArgs e) => this.AddActualEvent("MW");
-        }
 
-        protected override void OnWrittenByte()
+        private void AddActualEvent(string specifier)
         {
-            this.actualEvents.Add(new TestEvent(this.totalCycles + this.cpu.Cycles, "MW", this.Address.Word, this.Data));
+            var address = this.Address.Word;
-            base.OnWrittenByte();
+            var cycles = this.totalCycles + this.cpu.Cycles;
+            if (specifier.EndsWith('C'))
+            {
+                this.actualEvents.Add(new TestEvent(cycles, specifier, address));
+            }
+            else
+            {
+                this.actualEvents.Add(new TestEvent(cycles, specifier, address, this.Data));
+            }
         }
 
         private static void DumpDifference(string description, byte expected, byte actual)
@@ -121,11 +130,12 @@ namespace Z80.FuseTest
             Console.Error.WriteLine(output);
         }
 
-        private void Ports_WrittenPort(object? sender, EightBit.PortEventArgs e) => this.actualEvents.Add(new TestEvent(this.totalCycles + this.cpu.Cycles, "PW", this.Address.Word, this.Data));
+        private void Cpu_ExecutedInstruction(object? sender, EventArgs e)
-
+        {
-        private void Ports_ReadPort(object? sender, EightBit.PortEventArgs e) => this.actualEvents.Add(new TestEvent(this.totalCycles + this.cpu.Cycles, "PR", this.Address.Word, this.Data));
+            var output = $"**** Cycle count: {this.cpu.Cycles}";
-
+            Console.Out.WriteLine(output);
-        private void Cpu_ExecutedInstruction(object? sender, EventArgs e) => this.totalCycles += this.cpu.Cycles;
+            this.totalCycles += this.cpu.Cycles;
+        }
 
         private static void DumpDifference(string highDescription, string lowDescription, EightBit.Register16 expected, EightBit.Register16 actual)
         {

Z80/Z80.cs

@@ -5,12 +5,17 @@
 namespace Z80
 {
     using EightBit;
-    using System.Diagnostics;
 
-
+    public class Z80 : IntelProcessor
-    public class Z80(Bus bus, InputOutput ports) : IntelProcessor(bus)
     {
-        private readonly InputOutput _ports = ports;
+        public Z80(Bus bus, InputOutput ports)
+        : base(bus)
+        {
+            this._ports = ports;
+            this.RaisedPOWER += this.Z80_RaisedPOWER;
+        }
+
+        private readonly InputOutput _ports;
 
         private readonly Register16[] _accumulatorFlags = [new Register16(), new Register16()];
         private readonly Register16[][] _registers =
@@ -161,7 +166,7 @@ namespace Z80
             }
         }
 
-        protected override void OnRaisedPOWER()
+        private void Z80_RaisedPOWER(object? sender, EventArgs e)
         {
             this.RaiseM1();
             this.RaiseRFSH();
@@ -183,8 +188,6 @@ namespace Z80
             base.ResetWorkingRegisters();
 
             this.ResetPrefixes();
-
-            base.OnRaisedPOWER();
         }
 
         private void ResetPrefixes()
@@ -192,34 +195,7 @@ namespace Z80
             this._prefixCB = this._prefixDD = this._prefixED = this._prefixFD = false;
         }
 
-        private static void WithPinChange(Func<bool> check, Action enter, Action leave, Action task)
+        #region Z80 specific pins
-        {
-            if (check())
-            {
-                enter();
-                try
-                {
-                    task();
-                }
-                finally
-                {
-                    leave();
-                }
-            }
-        }
-
-        private static byte WithPin(Action enter, Action leave, Func<byte> task)
-        {
-            enter();
-            try
-            {
-                return task();
-            }
-            finally
-            {
-                leave();
-            }
-        }
 
         #region NMI pin
 
@@ -235,22 +211,14 @@ namespace Z80
 
         public ref PinLevel NMI => ref this._nmiLine;
 
-        protected virtual void OnRaisingNMI() => RaisingNMI?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisedNMI() => RaisedNMI?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnLoweringNMI() => LoweringNMI?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnLoweredNMI() => LoweredNMI?.Invoke(this, EventArgs.Empty);
-
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1030:Use events where appropriate", Justification = "The word 'raise' is used in an electrical sense")]
         public virtual void RaiseNMI()
         {
             if (this.NMI.Lowered())
             {
-                this.OnRaisingNMI();
+                RaisingNMI?.Invoke(this, EventArgs.Empty);
                 this.NMI.Raise();
-                this.OnRaisedNMI();
+                RaisedNMI?.Invoke(this, EventArgs.Empty);
             }
         }
 
@@ -258,9 +226,9 @@ namespace Z80
         {
             if (this.NMI.Raised())
             {
-                this.OnLoweringNMI();
+                LoweringNMI?.Invoke(this, EventArgs.Empty);
                 this.NMI.Lower();
-                this.OnLoweredNMI();
+                LoweredNMI?.Invoke(this, EventArgs.Empty);
             }
         }
 
@@ -280,14 +248,6 @@ namespace Z80
 
         public ref PinLevel M1 => ref this._m1Line;
 
-        protected virtual void OnRaisingM1() => RaisingM1?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisedM1()
-        {
-            ++this.REFRESH;
-            RaisedM1?.Invoke(this, EventArgs.Empty);
-        }
-
         protected virtual void OnLoweringM1() => LoweringM1?.Invoke(this, EventArgs.Empty);
 
         protected virtual void OnLoweredM1() => LoweredM1?.Invoke(this, EventArgs.Empty);
@@ -295,17 +255,23 @@ namespace Z80
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1030:Use events where appropriate", Justification = "The word 'raise' is used in an electrical sense")]
         public virtual void RaiseM1()
         {
-            WithPinChange(() => this.M1.Lowered(), this.OnRaisingM1, this.OnRaisedM1, () => this.M1.Raise());
+            if (this.M1.Lowered())
+            {
+                RaisingM1?.Invoke(this, EventArgs.Empty);
+                this.M1.Raise();
+                ++this.REFRESH;
+                RaisedM1?.Invoke(this, EventArgs.Empty);
+            }
         }
 
         public virtual void LowerM1()
         {
-            WithPinChange(() => this.M1.Raised(), this.OnLoweringM1, this.OnLoweredM1, () => this.M1.Lower());
+            if (this.M1.Raised())
-        }
+            {
-
+                LoweringM1?.Invoke(this, EventArgs.Empty);
-        private byte WithM1(Func<byte> function)
+                this.M1.Lower();
-        {
+                LoweredM1?.Invoke(this, EventArgs.Empty);
-            return WithPin(this.LowerM1, this.RaiseM1, function);
+            }
         }
 
         #endregion
@@ -329,28 +295,25 @@ namespace Z80
 
         public ref PinLevel RFSH => ref this._rfshLine;
 
-        protected virtual void OnRaisingRFSH() => RaisingRFSH?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisedRFSH() => RaisedRFSH?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnLoweringRFSH() => LoweringRFSH?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnLoweredRFSH() => LoweredRFSH?.Invoke(this, EventArgs.Empty);
-
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1030:Use events where appropriate", Justification = "The word 'raise' is used in an electrical sense")]
         public virtual void RaiseRFSH()
         {
-            WithPinChange(() => this.RFSH.Lowered(), this.OnRaisingRFSH, this.OnRaisedRFSH, () => this.RFSH.Raise());
+            if (this.RFSH.Lowered())
+            {
+                RaisingRFSH?.Invoke(this, EventArgs.Empty);
+                this.RFSH.Raise();
+                RaisedRFSH?.Invoke(this, EventArgs.Empty);
+            }
         }
 
         public virtual void LowerRFSH()
         {
-            WithPinChange(() => this.RFSH.Raised(), this.OnLoweringRFSH, this.OnLoweredRFSH, () => this.RFSH.Lower());
+            if (this.RFSH.Raised())
-        }
+            {
-
+                LoweringRFSH?.Invoke(this, EventArgs.Empty);
-        private byte WithRFSH(Func<byte> function)
+                this.RFSH.Lower();
-        {
+                LoweredRFSH?.Invoke(this, EventArgs.Empty);
-            return WithPin(this.LowerRFSH, this.RaiseRFSH, function);
+            }
         }
 
         #endregion
@@ -369,28 +332,25 @@ namespace Z80
 
         public ref PinLevel MREQ => ref this._mreqLine;
 
-        protected virtual void OnLoweringMREQ() => LoweringMREQ?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnLoweredMREQ() => LoweredMREQ?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisingMREQ() => RaisingMREQ?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisedMREQ() => RaisedMREQ?.Invoke(this, EventArgs.Empty);
-
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1030:Use events where appropriate", Justification = "The word 'raise' is used in an electrical sense")]
         public virtual void RaiseMREQ()
         {
-            WithPinChange(() => this.MREQ.Lowered(), this.OnRaisingMREQ, this.OnRaisedMREQ, () => this.MREQ.Raise());
+            if (this.MREQ.Lowered())
+            {
+                RaisingMREQ?.Invoke(this, EventArgs.Empty);
+                this.MREQ.Raise();
+                RaisedMREQ?.Invoke(this, EventArgs.Empty);
+            }
         }
 
         public virtual void LowerMREQ()
         {
-            WithPinChange(() => this.MREQ.Raised(), this.OnLoweringMREQ, this.OnLoweredMREQ, () => this.MREQ.Lower());
+            if (this.MREQ.Raised())
-        }
+            {
-
+                LoweringMREQ?.Invoke(this, EventArgs.Empty);
-        private byte WithMREQ(Func<byte> function)
+                this.MREQ.Lower();
-        {
+                LoweredMREQ?.Invoke(this, EventArgs.Empty);
-            return WithPin(this.LowerMREQ, this.RaiseMREQ, function);
+            }
         }
 
         #endregion
@@ -409,29 +369,25 @@ namespace Z80
 
         public ref PinLevel IORQ => ref this._iorqLine;
 
-        protected virtual void OnLoweringIORQ() => LoweringIORQ?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnLoweredIORQ() => LoweredIORQ?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisingIORQ() => RaisingIORQ?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisedIORQ() => RaisedIORQ?.Invoke(this, EventArgs.Empty);
-
-
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1030:Use events where appropriate", Justification = "The word 'raise' is used in an electrical sense")]
         public virtual void RaiseIORQ()
         {
-            WithPinChange(() => this.IORQ.Lowered(), this.OnRaisingIORQ, this.OnRaisedIORQ, () => this.IORQ.Raise());
+            if (this.IORQ.Lowered())
+            {
+                RaisingIORQ?.Invoke(this, EventArgs.Empty);
+                this.IORQ.Raise();
+                RaisedIORQ?.Invoke(this, EventArgs.Empty);
+            }
         }
 
         public virtual void LowerIORQ()
         {
-            WithPinChange(() => this.IORQ.Raised(), this.OnLoweringIORQ, this.OnLoweredIORQ, () => this.IORQ.Lower());
+            if (this.IORQ.Raised())
-        }
+            {
-
+                LoweringIORQ?.Invoke(this, EventArgs.Empty);
-        private byte WithIORQ(Func<byte> function)
+                this.IORQ.Lower();
-        {
+                LoweredIORQ?.Invoke(this, EventArgs.Empty);
-            return WithPin(this.LowerIORQ, this.RaiseIORQ, function);
+            }
         }
 
         #endregion
@@ -450,28 +406,25 @@ namespace Z80
 
         public ref PinLevel RD => ref this._rdLine;
 
-        protected virtual void OnLoweringRD() => LoweringRD?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnLoweredRD() => LoweredRD?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisingRD() => RaisingRD?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisedRD() => RaisedRD?.Invoke(this, EventArgs.Empty);
-
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1030:Use events where appropriate", Justification = "The word 'raise' is used in an electrical sense")]
         public virtual void RaiseRD()
         {
-            WithPinChange(() => this.RD.Lowered(), this.OnRaisingRD, this.OnRaisedRD, () => this.RD.Raise());
+            if (this.RD.Lowered())
+            {
+                RaisingRD?.Invoke(this, EventArgs.Empty);
+                this.RD.Raise();
+                RaisedRD?.Invoke(this, EventArgs.Empty);
+            }
         }
 
         public virtual void LowerRD()
         {
-            WithPinChange(() => this.RD.Raised(), this.OnLoweringRD, this.OnLoweredRD, () => this.RD.Lower());
+            if (this.RD.Raised())
-        }
+            {
-
+                LoweringRD?.Invoke(this, EventArgs.Empty);
-        private byte WithRD(Func<byte> function)
+                this.RD.Lower();
-        {
+                LoweredRD?.Invoke(this, EventArgs.Empty);
-            return WithPin(this.LowerRD, this.RaiseRD, function);
+            }
         }
 
         #endregion
@@ -490,63 +443,50 @@ namespace Z80
 
         public ref PinLevel WR => ref this._wrLine;
 
-        protected virtual void OnLoweringWR() => LoweringWR?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnLoweredWR() => LoweredWR?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisingWR() => RaisingWR?.Invoke(this, EventArgs.Empty);
-
-        protected virtual void OnRaisedWR() => RaisedWR?.Invoke(this, EventArgs.Empty);
-
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1030:Use events where appropriate", Justification = "The word 'raise' is used in an electrical sense")]
         public virtual void RaiseWR()
         {
-            WithPinChange(() => this.WR.Lowered(), this.OnRaisingWR, this.OnRaisedWR, () => this.WR.Raise());
+            if (this.WR.Lowered())
+            {
+                RaisingWR?.Invoke(this, EventArgs.Empty);
+                this.WR.Raise();
+                RaisedWR?.Invoke(this, EventArgs.Empty);
+            }
         }
 
         public virtual void LowerWR()
         {
-            WithPinChange(() => this.WR.Raised(), this.OnLoweringWR, this.OnLoweredWR, () => this.WR.Lower());
+            if (this.WR.Raised())
-        }
-
-        private byte WithWR(Func<byte> function)
-        {
-            this.LowerWR();
-            try
             {
-                return function();
+                LoweringWR?.Invoke(this, EventArgs.Empty);
-            }
+                this.WR.Lower();
-            finally
+                LoweredWR?.Invoke(this, EventArgs.Empty);
-            {
-                this.RaiseWR();
             }
         }
 
         #endregion
 
+        #endregion
+
         protected override void MemoryWrite()
         {
-            _ = this.WithMREQ(() =>
+            this.LowerMREQ();
-            {
+            this.LowerWR();
-                return this.WithWR(() =>
+            this.Tick(3);
-                {
+            base.MemoryWrite();
-                    this.Tick(3);
+            this.RaiseWR();
-                    base.MemoryWrite();
+            this.RaiseMREQ();
-                    return 0;
-                });
-            });
         }
 
         protected override byte MemoryRead()
         {
-            return this.WithMREQ(() =>
+            this.LowerMREQ();
-            {
+            this.LowerRD();
-                return this.WithRD(() =>
+            this.Tick(3);
-                {
+            var returned = base.MemoryRead();
-                    this.Tick(3);
+            this.RaiseRD();
-                    return base.MemoryRead();
+            this.RaiseMREQ();
-                });
+            return returned;
-            });
         }
 
         protected override void HandleRESET()
@@ -562,13 +502,11 @@ namespace Z80
         {
             base.HandleINT();
 
-            var data = this.WithM1(() =>
+            this.LowerM1();
-            {
+            this.LowerIORQ();
-                return this.WithIORQ(() =>
+            var data = this.Bus.Data;
-                {
+            this.RaiseIORQ();
-                    return this.Bus.Data;
+            this.RaiseM1();
-                });
-            });
 
             this.DisableInterrupts();
             this.Tick(5);
@@ -1723,18 +1661,17 @@ namespace Z80
         private byte ReadInitialOpCode()
         {
             this.Tick();
-            var returned = this.WithM1(() =>
+
-            {
+            this.LowerM1();
-                return this.MemoryRead(this.PC);
+            var returned = this.MemoryRead(this.PC);
-            });
+            this.RaiseM1();
+
             this.Bus.Address.Assign(this.REFRESH, this.IV);
-            _ = this.WithRFSH(() =>
+            this.LowerRFSH();
-            {
+            this.LowerMREQ();
-                return this.WithMREQ(() =>
+            this.RaiseMREQ();
-                {
+            this.RaiseRFSH();
-                    return 0;
+
-                });
-            });
             return returned;
         }