Follow most of the guideline suggestions from VS2019 preview. Pretty good suggestions!

Signed-off-by: Adrian Conlon <Adrian.conlon@gmail.com>

EightBit/Chip.cs

@@ -54,7 +54,7 @@ namespace EightBit
 
         public static int CountBits(int value)
         {
-            int count = 0;
+            var count = 0;
             while (value != 0)
             {
                 ++count;

EightBit/ClockedChip.cs

@@ -18,7 +18,7 @@ namespace EightBit
 
         public void Tick(int extra)
         {
-            for (int i = 0; i < extra; ++i)
+            for (var i = 0; i < extra; ++i)
             {
                 this.Tick();
             }

EightBit/IntelProcessor.cs

@@ -18,7 +18,7 @@ namespace EightBit
         protected IntelProcessor(Bus bus)
         : base(bus)
         {
-            for (int i = 0; i < 0x100; ++i)
+            for (var i = 0; i < 0x100; ++i)
             {
                 this.decodedOpCodes[i] = new IntelOpCodeDecoded((byte)i);
             }
@@ -87,10 +87,7 @@ namespace EightBit
             this.OnLoweredHALT();
         }
 
-        protected static int BuildHalfCarryIndex(byte before, byte value, int calculation)
+        protected static int BuildHalfCarryIndex(byte before, byte value, int calculation) => ((before & 0x88) >> 1) | ((value & 0x88) >> 2) | ((calculation & 0x88) >> 3);
-        {
-            return ((before & 0x88) >> 1) | ((value & 0x88) >> 2) | ((calculation & 0x88) >> 3);
-        }
 
         protected static int CalculateHalfCarryAdd(byte before, byte value, int calculation)
         {

EightBit/Processor.cs

@@ -48,7 +48,7 @@ namespace EightBit
 
         public int Run(int limit)
         {
-            int current = 0;
+            var current = 0;
             while (this.Powered && (current < limit))
             {
                 current += this.Step();

EightBit/Register16.cs

@@ -45,10 +45,7 @@ namespace EightBit
 
         public ushort Word
         {
-            get
+            get => (ushort)(this.Low | Chip.PromoteByte(this.High));
-            {
-                return (ushort)(this.Low | Chip.PromoteByte(this.High));
-            }
 
             set
             {
@@ -84,12 +81,7 @@ namespace EightBit
         public override bool Equals(object obj)
         {
             var rhs = obj as Register16;
-            if (rhs == null)
+            return rhs == null ? false : rhs.Low == this.Low && rhs.High == this.High;
-            {
-                return false;
-            }
-
-            return rhs.Low == this.Low && rhs.High == this.High;
         }
 
         public override int GetHashCode() => this.Word;

M6502/Disassembler.cs

@@ -34,15 +34,9 @@ namespace EightBit
             return returned.ToString();
         }
 
-        public static string Dump_ByteValue(byte value)
+        public static string Dump_ByteValue(byte value) => value.ToString("X2");
-        {
-            return value.ToString("X2");
-        }
 
-        public static string Dump_WordValue(ushort value)
+        public static string Dump_WordValue(ushort value) => value.ToString("X4");
-        {
-            return value.ToString("X4");
-        }
 
         public string Disassemble(ushort current)
         {
@@ -503,215 +497,81 @@ namespace EightBit
             return output.ToString();
         }
 
-        private string ConvertAddress(ushort absolute)
+        private string ConvertAddress(ushort absolute) => this.symbols.Labels.TryGetValue(absolute, out var label) ? label : "$" + Dump_WordValue(absolute);
-        {
-            if (this.symbols.Labels.TryGetValue(absolute, out string label))
-            {
-                return label;
-            }
 
-            return "$" + Dump_WordValue(absolute);
+        private string ConvertAddress(byte absolute) => this.symbols.Labels.TryGetValue(absolute, out var label) ? label : "$" + Dump_ByteValue(absolute);
-        }
 
-        private string ConvertAddress(byte absolute)
+        private string ConvertConstant(ushort constant) => this.symbols.Constants.TryGetValue(constant, out var label) ? label : this.Dump_DByte(constant);
-        {
-            if (this.symbols.Labels.TryGetValue(absolute, out string label))
-            {
-                return label;
-            }
 
-            return "$" + Dump_ByteValue(absolute);
+        private string ConvertConstant(byte constant) => this.symbols.Constants.TryGetValue(constant, out var label) ? label : Dump_ByteValue(constant);
-        }
 
-        private string ConvertConstant(ushort constant)
+        private byte GetByte(ushort absolute) => this.bus.Peek(absolute);
-        {
-            if (this.symbols.Constants.TryGetValue(constant, out string label))
-            {
-                return label;
-            }
 
-            return this.Dump_DByte(constant);
+        private ushort GetWord(ushort absolute) => this.processor.PeekWord(absolute).Word;
-        }
 
-        private string ConvertConstant(byte constant)
+        private string Dump_Byte(ushort absolute) => Disassembler.Dump_ByteValue(this.GetByte(absolute));
-        {
-            if (this.symbols.Constants.TryGetValue(constant, out string label))
-            {
-                return label;
-            }
 
-            return Dump_ByteValue(constant);
+        private string Dump_DByte(ushort absolute) => this.Dump_Byte(absolute) + " " + this.Dump_Byte(++absolute);
-        }
 
-        private byte GetByte(ushort absolute)
+        private string Dump_Word(ushort absolute) => Disassembler.Dump_WordValue(this.GetWord(absolute));
-        {
-            return this.bus.Peek(absolute);
-        }
 
-        private ushort GetWord(ushort absolute)
+        private string Disassemble_Implied(string instruction) => "\t" + instruction;
-        {
-            return this.processor.PeekWord(absolute).Word;
-        }
 
-        private string Dump_Byte(ushort absolute)
+        private string Disassemble_Absolute(string instruction) => this.AM_Absolute_dump() + "\t" + instruction + " " + this.AM_Absolute();
-        {
-            return Disassembler.Dump_ByteValue(this.GetByte(absolute));
-        }
 
-        private string Dump_DByte(ushort absolute)
+        private string Disassemble_Indirect(string instruction) => this.AM_Absolute_dump() + "\t" + instruction + " (" + this.AM_Absolute() + ")";
-        {
-            return this.Dump_Byte(absolute) + " " + this.Dump_Byte(++absolute);
-        }
 
-        private string Dump_Word(ushort absolute)
+        private string Disassemble_Relative(string instruction, ushort absolute) => this.AM_Immediate_dump() + "\t" + instruction + " $" + Disassembler.Dump_WordValue(absolute);
-        {
-            return Disassembler.Dump_WordValue(this.GetWord(absolute));
-        }
 
-        private string Disassemble_Implied(string instruction)
+        private string Disassemble_Immediate(string instruction) => this.AM_Immediate_dump() + "\t" + instruction + " " + this.AM_Immediate();
-        {
-            return "\t" + instruction;
-        }
 
-        private string Disassemble_Absolute(string instruction)
+        private string Disassemble_AM_00(int bbb, string instruction) => this.AM_00_dump(bbb) + "\t" + instruction + " " + this.AM_00(bbb);
-        {
-            return this.AM_Absolute_dump() + "\t" + instruction + " " + this.AM_Absolute();
-        }
 
-        private string Disassemble_Indirect(string instruction)
+        private string Disassemble_AM_01(int bbb, string instruction) => this.AM_01_dump(bbb) + "\t" + instruction + " " + this.AM_01(bbb);
-        {
-            return this.AM_Absolute_dump() + "\t" + instruction + " (" + this.AM_Absolute() + ")";
-        }
 
-        private string Disassemble_Relative(string instruction, ushort absolute)
+        private string Disassemble_AM_10(int bbb, string instruction) => this.AM_10_dump(bbb) + "\t" + instruction + " " + this.AM_10(bbb);
-        {
-            return this.AM_Immediate_dump() + "\t" + instruction + " $" + Disassembler.Dump_WordValue(absolute);
-        }
 
-        private string Disassemble_Immediate(string instruction)
+        private string Disassemble_AM_10_x(int bbb, string instruction) => this.AM_10_x_dump(bbb) + "\t" + instruction + " " + this.AM_10_x(bbb);
-        {
-            return this.AM_Immediate_dump() + "\t" + instruction + " " + this.AM_Immediate();
-        }
 
-        private string Disassemble_AM_00(int bbb, string instruction)
+        private string Disassemble_AM_11(int bbb, string instruction) => this.AM_11_dump(bbb) + "\t" + instruction + " " + this.AM_11(bbb);
-        {
-            return this.AM_00_dump(bbb) + "\t" + instruction + " " + this.AM_00(bbb);
-        }
 
-        private string Disassemble_AM_01(int bbb, string instruction)
+        private string Disassemble_AM_11_x(int bbb, string instruction) => this.AM_11_x_dump(bbb) + "\t" + instruction + " " + this.AM_11_x(bbb);
-        {
-            return this.AM_01_dump(bbb) + "\t" + instruction + " " + this.AM_01(bbb);
-        }
 
-        private string Disassemble_AM_10(int bbb, string instruction)
+        private string AM_Immediate_dump() => this.Dump_Byte((ushort)(this.address + 1));
-        {
-            return this.AM_10_dump(bbb) + "\t" + instruction + " " + this.AM_10(bbb);
-        }
 
-        private string Disassemble_AM_10_x(int bbb, string instruction)
+        private string AM_Immediate() => "#$" + this.AM_Immediate_dump();
-        {
-            return this.AM_10_x_dump(bbb) + "\t" + instruction + " " + this.AM_10_x(bbb);
-        }
 
-        private string Disassemble_AM_11(int bbb, string instruction)
+        private string AM_Absolute_dump() => this.Dump_DByte((ushort)(this.address + 1));
-        {
-            return this.AM_11_dump(bbb) + "\t" + instruction + " " + this.AM_11(bbb);
-        }
 
-        private string Disassemble_AM_11_x(int bbb, string instruction)
+        private string AM_Absolute() => "$" + this.Dump_Word((ushort)(this.address + 1));
-        {
-            return this.AM_11_x_dump(bbb) + "\t" + instruction + " " + this.AM_11_x(bbb);
-        }
 
-        private string AM_Immediate_dump()
+        private string AM_ZeroPage_dump() => this.Dump_Byte((ushort)(this.address + 1));
-        {
-            return this.Dump_Byte((ushort)(this.address + 1));
-        }
 
-        private string AM_Immediate()
+        private string AM_ZeroPage() => "$" + this.Dump_Byte((ushort)(this.address + 1));
-        {
-            return "#$" + this.AM_Immediate_dump();
-        }
 
-        private string AM_Absolute_dump()
+        private string AM_ZeroPageX_dump() => this.AM_ZeroPage_dump();
-        {
-            return this.Dump_DByte((ushort)(this.address + 1));
-        }
 
-        private string AM_Absolute()
+        private string AM_ZeroPageX() => this.AM_ZeroPage() + ",X";
-        {
-            return "$" + this.Dump_Word((ushort)(this.address + 1));
-        }
 
-        private string AM_ZeroPage_dump()
+        private string AM_ZeroPageY_dump() => this.AM_ZeroPage_dump();
-        {
-            return this.Dump_Byte((ushort)(this.address + 1));
-        }
 
-        private string AM_ZeroPage()
+        private string AM_ZeroPageY() => this.AM_ZeroPage() + ",Y";
-        {
-            return "$" + this.Dump_Byte((ushort)(this.address + 1));
-        }
 
-        private string AM_ZeroPageX_dump()
+        private string AM_AbsoluteX_dump() => this.AM_Absolute_dump();
-        {
-            return this.AM_ZeroPage_dump();
-        }
 
-        private string AM_ZeroPageX()
+        private string AM_AbsoluteX() => this.AM_Absolute() + ",X";
-        {
-            return this.AM_ZeroPage() + ",X";
-        }
 
-        private string AM_ZeroPageY_dump()
+        private string AM_AbsoluteY_dump() => this.AM_Absolute_dump();
-        {
-            return this.AM_ZeroPage_dump();
-        }
 
-        private string AM_ZeroPageY()
+        private string AM_AbsoluteY() => this.AM_Absolute() + ",Y";
-        {
-            return this.AM_ZeroPage() + ",Y";
-        }
 
-        private string AM_AbsoluteX_dump()
+        private string AM_IndexedIndirectX_dump() => this.AM_ZeroPage_dump();
-        {
-            return this.AM_Absolute_dump();
-        }
 
-        private string AM_AbsoluteX()
+        private string AM_IndexedIndirectX() => "($" + this.Dump_Byte((ushort)(this.address + 1)) + ",X)";
-        {
-            return this.AM_Absolute() + ",X";
-        }
 
-        private string AM_AbsoluteY_dump()
+        private string AM_IndirectIndexedY_dump() => this.AM_ZeroPage_dump();
-        {
-            return this.AM_Absolute_dump();
-        }
 
-        private string AM_AbsoluteY()
+        private string AM_IndirectIndexedY() => "($" + this.Dump_Byte((ushort)(this.address + 1)) + "),Y";
-        {
-            return this.AM_Absolute() + ",Y";
-        }
-
-        private string AM_IndexedIndirectX_dump()
-        {
-            return this.AM_ZeroPage_dump();
-        }
-
-        private string AM_IndexedIndirectX()
-        {
-            return "($" + this.Dump_Byte((ushort)(this.address + 1)) + ",X)";
-        }
-
-        private string AM_IndirectIndexedY_dump()
-        {
-            return this.AM_ZeroPage_dump();
-        }
-
-        private string AM_IndirectIndexedY()
-        {
-            return "($" + this.Dump_Byte((ushort)(this.address + 1)) + "),Y";
-        }
 
         private string AM_00_dump(int bbb)
         {

M6502/M6502.Test/Board.cs

@@ -50,7 +50,6 @@ namespace M6502.Test
 
         public override void Initialize()
         {
-            var programFilename = this.configuration.Program;
             var programPath = this.configuration.RomDirectory + "/" + this.configuration.Program;
             var loadAddress = this.configuration.LoadAddress;
             this.ram.Load(programPath, loadAddress.Word);
@@ -88,7 +87,6 @@ namespace M6502.Test
         private void CPU_ExecutingInstruction(object sender, System.EventArgs e)
         {
             var address = this.CPU.PC.Word;
-            var cell = this.Peek(address);
 
             var output = new StringBuilder();
 

M6502/M6502.Test/Configuration.cs

@@ -8,28 +8,18 @@ namespace M6502.Test
 
     internal class Configuration
     {
-        private readonly Register16 loadAddress = new Register16(0x400);
-        private readonly Register16 startAddress = new Register16(0x400);
-        private readonly string romDirectory = "roms";
-        private readonly string program = "6502_functional_test.bin";
-        private bool debugMode = false;
-
         public Configuration()
         {
         }
 
-        public bool DebugMode
+        public bool DebugMode { get; set; } = false;
-        {
-            get => this.debugMode;
-            set => this.debugMode = value;
-        }
 
-        public Register16 LoadAddress { get => this.loadAddress; }
+        public Register16 LoadAddress { get; } = new Register16(0x400);
 
-        public Register16 StartAddress { get => this.startAddress; }
+        public Register16 StartAddress { get; } = new Register16(0x400);
 
-        public string RomDirectory { get => this.romDirectory; }
+        public string RomDirectory { get; } = "roms";
 
-        public string Program { get => this.program; }
+        public string Program { get; } = "6502_functional_test.bin";
     }
 }

M6502/M6502.Test/TestHarness.cs

@@ -12,14 +12,10 @@ namespace M6502.Test
         private readonly Stopwatch timer = new Stopwatch();
         private readonly Board board;
         private long totalCycles = 0;
-        private long instructions = 0;
 
         private bool disposed = false;
 
-        public TestHarness(Configuration configuration)
+        public TestHarness(Configuration configuration) => this.board = new Board(configuration);
-        {
-            this.board = new Board(configuration);
-        }
 
         public void Dispose()
         {
@@ -38,7 +34,6 @@ namespace M6502.Test
             while (cpu.Powered)
             {
                 this.totalCycles += cpu.Step();
-                ++this.instructions;
             }
 
             this.timer.Stop();

M6502/M6502.cs

@@ -555,8 +555,6 @@ namespace EightBit
 
         private static byte ClearFlag(byte f, StatusBits flag, int condition) => ClearFlag(f, (byte)flag, condition);
 
-        private static byte ClearFlag(byte f, StatusBits flag, bool condition) => ClearFlag(f, (byte)flag, condition);
-
         private void HandleNMI()
         {
             this.RaiseNMI();
@@ -769,10 +767,7 @@ namespace EightBit
             return returned;
         }
 
-        private byte SUB(byte operand, byte data, int borrow = 0)
+        private byte SUB(byte operand, byte data, int borrow = 0) => this.Decimal != 0 ? this.SUB_d(operand, data, borrow) : this.SUB_b(operand, data, borrow);
-        {
-            return this.Decimal != 0 ? this.SUB_d(operand, data, borrow) : this.SUB_b(operand, data, borrow);
-        }
 
         private byte SUB_b(byte operand, byte data, int borrow)
         {
@@ -808,10 +803,7 @@ namespace EightBit
             return returned;
         }
 
-        private byte ADD(byte operand, byte data, int carry = 0)
+        private byte ADD(byte operand, byte data, int carry = 0) => this.Decimal != 0 ? this.ADD_d(operand, data, carry) : this.ADD_b(operand, data, carry);
-        {
-            return this.Decimal != 0 ? this.ADD_d(operand, data, carry) : this.ADD_b(operand, data, carry);
-        }
 
         private byte ADD_b(byte operand, byte data, int carry)
         {

Z80/Disassembler.cs

@@ -4,29 +4,21 @@
 
 namespace EightBit
 {
-    using System.Text;
-
     public class Disassembler
     {
-        private readonly Bus bus;
-
         private bool prefixCB = false;
         private bool prefixDD = false;
         private bool prefixED = false;
         private bool prefixFD = false;
 
-        public Disassembler(Bus bus)
+        public Disassembler(Bus bus) => this.Bus = bus;
-        {
-            this.bus = bus;
-        }
 
-        public Bus Bus => this.bus;
+        public Bus Bus { get; }
 
         public static string AsFlag(byte value, StatusBits flag, string represents) => (value & (byte)flag) != 0 ? represents : "-";
 
-        public static string AsFlags(byte value)
+        public static string AsFlags(byte value) =>
-        {
+                   $"{AsFlag(value, StatusBits.SF, "S")}"
-            return $"{AsFlag(value, StatusBits.SF, "S")}"
                  + $"{AsFlag(value, StatusBits.ZF, "Z")}"
                  + $"{AsFlag(value, StatusBits.YF, "Y")}"
                  + $"{AsFlag(value, StatusBits.HC, "H")}"
@@ -34,7 +26,6 @@ namespace EightBit
                  + $"{AsFlag(value, StatusBits.PF, "P")}"
                  + $"{AsFlag(value, StatusBits.NF, "N")}"
                  + $"{AsFlag(value, StatusBits.CF, "C")}";
-        }
 
         public static string State(Z80 cpu)
         {
@@ -147,10 +138,10 @@ namespace EightBit
 
             var output = $"{opCode:x2}";
 
-            string specification = string.Empty;
+            var specification = string.Empty;
             if (this.prefixCB)
             {
-                output += this.DisassembleCB(cpu, pc, ref specification, ref dumpCount, x, y, z, p, q);
+                output += this.DisassembleCB(ref specification, x, y, z);
             }
             else if (this.prefixED)
             {
@@ -161,7 +152,7 @@ namespace EightBit
                 output += this.DisassembleOther(cpu, pc, ref specification, ref dumpCount, x, y, z, p, q);
             }
 
-            for (int i = 0; i < dumpCount; ++i)
+            for (var i = 0; i < dumpCount; ++i)
             {
                 output += $"{this.Bus.Peek((ushort)(pc + i + 1)):x2}";
             }
@@ -184,9 +175,9 @@ namespace EightBit
             return output;
         }
 
-        private string DisassembleCB(Z80 cpu, ushort pc, ref string specification, ref int dumpCount, int x, int y, int z, int p, int q)
+        private string DisassembleCB(ref string specification, int x, int y, int z)
         {
-            string output = string.Empty;
+            var output = string.Empty;
             switch (x)
             {
                 case 0: // rot[y] r[z]

Z80/RefreshRegister.cs

@@ -15,15 +15,9 @@ namespace EightBit
             this.variable = (byte)(value & (byte)Mask.Mask7);
         }
 
-        public static implicit operator byte(RefreshRegister input)
+        public static implicit operator byte(RefreshRegister input) => ToByte(input);
-        {
-            return ToByte(input);
-        }
 
-        public static implicit operator RefreshRegister(byte input)
+        public static implicit operator RefreshRegister(byte input) => FromByte(input);
-        {
-            return FromByte(input);
-        }
 
         public static RefreshRegister operator ++(RefreshRegister value) => Increment(value);
 
@@ -31,10 +25,7 @@ namespace EightBit
 
         public static bool operator !=(RefreshRegister left, RefreshRegister right) => !(left == right);
 
-        public static byte ToByte(RefreshRegister input)
+        public static byte ToByte(RefreshRegister input) => (byte)((input.high << 7) | (input.variable & (byte)Mask.Mask7));
-        {
-            return (byte)((input.high << 7) | (input.variable & (byte)Mask.Mask7));
-        }
 
         public static RefreshRegister Increment(RefreshRegister value)
         {
@@ -42,15 +33,9 @@ namespace EightBit
             return value;
         }
 
-        public static RefreshRegister FromByte(byte input)
+        public static RefreshRegister FromByte(byte input) => new RefreshRegister(input);
-        {
-            return new RefreshRegister(input);
-        }
 
-        public byte ToByte()
+        public byte ToByte() => ToByte(this);
-        {
-            return ToByte(this);
-        }
 
         public override bool Equals(object obj)
         {

Z80/Z80.Test/Board.cs

@@ -46,7 +46,6 @@ namespace Z80.Test
 
         public override void Initialize()
         {
-            var programFilename = this.configuration.Program;
             var programPath = this.configuration.RomDirectory + "/" + this.configuration.Program;
             var loadAddress = this.configuration.LoadAddress;
             this.ram.Load(programPath, loadAddress.Word);
@@ -68,15 +67,15 @@ namespace Z80.Test
 
         private void BDOS()
         {
-            switch (CPU.C)
+            switch (this.CPU.C)
             {
                 case 0x2:
-                    System.Console.Out.Write(CPU.E.ToString());
+                    System.Console.Out.Write(this.CPU.E.ToString());
                     break;
                 case 0x9:
-                    for (ushort i = CPU.DE.Word; Peek(i) != '$'; ++i)
+                    for (var i = this.CPU.DE.Word; this.Peek(i) != '$'; ++i)
                     {
-                        System.Console.Out.Write((char)Peek(i));
+                        System.Console.Out.Write((char)this.Peek(i));
                     }
 
                     break;
@@ -95,21 +94,15 @@ namespace Z80.Test
 
                     break;
                 case 0x5:   // BDOS
-                    BDOS();
+                    this.BDOS();
                     break;
                 default:
                     break;
             }
         }
 
-        private void CPU_LoweredHALT(object sender, System.EventArgs e)
+        private void CPU_LoweredHALT(object sender, System.EventArgs e) => this.LowerPOWER();
-        {
-            this.LowerPOWER();
-        }
 
-        private void CPU_ExecutingInstruction_Debug(object sender, System.EventArgs e)
+        private void CPU_ExecutingInstruction_Debug(object sender, System.EventArgs e) => System.Console.Error.WriteLine($"{EightBit.Disassembler.State(this.CPU)}\t{this.disassembler.Disassemble(this.CPU)}");
-        {
-            System.Console.Error.WriteLine($"{EightBit.Disassembler.State(this.CPU)}\t{this.disassembler.Disassemble(this.CPU)}");
-        }
     }
 }

Z80/Z80.Test/Program.cs

@@ -13,7 +13,6 @@ namespace Z80.Test
 #if DEBUG
             configuration.DebugMode = true;
 #endif
-           // configuration.DebugMode = true;
 
             using (var harness = new TestHarness(configuration))
             {

Z80/Z80.Test/TestHarness.cs

@@ -12,14 +12,10 @@ namespace Z80.Test
         private readonly Stopwatch timer = new Stopwatch();
         private readonly Board board;
         private long totalCycles = 0;
-        private long instructions = 0;
 
         private bool disposed = false;
 
-        public TestHarness(Configuration configuration)
+        public TestHarness(Configuration configuration) => this.board = new Board(configuration);
-        {
-            this.board = new Board(configuration);
-        }
 
         public void Dispose()
         {
@@ -38,7 +34,6 @@ namespace Z80.Test
             while (cpu.Powered)
             {
                 this.totalCycles += cpu.Step();
-                ++this.instructions;
             }
 
             this.timer.Stop();

Z80/Z80.cs

@@ -28,7 +28,6 @@ namespace EightBit
         private bool prefixCB = false;
         private bool prefixDD = false;
         private bool prefixED = false;
-        private bool prefixFD = false;
 
         private PinLevel nmiLine = PinLevel.Low;
         private PinLevel m1Line = PinLevel.Low;
@@ -40,10 +39,7 @@ namespace EightBit
         private bool displaced = false;
 
         public Z80(Bus bus, InputOutput ports)
-        : base(bus)
+        : base(bus) => this.ports = ports;
-        {
-            this.ports = ports;
-        }
 
         public event EventHandler<EventArgs> ExecutingInstruction;
 
@@ -130,7 +126,7 @@ namespace EightBit
             this.Exx();
             this.IX.Word = this.IY.Word = this.BC.Word = this.DE.Word = this.HL.Word = (ushort)Mask.Mask16;
 
-            this.prefixCB = this.prefixDD = this.prefixED = this.prefixFD = false;
+            this.prefixCB = this.prefixDD = this.prefixED = false;
         }
 
         public virtual void RaiseNMI()
@@ -204,7 +200,7 @@ namespace EightBit
             this.OnExecutingInstruction();
             if (this.Powered)
             {
-                this.displaced = this.prefixCB = this.prefixDD = this.prefixED = this.prefixFD = false;
+                this.displaced = this.prefixCB = this.prefixDD = this.prefixED = false;
                 this.LowerM1();
                 if (this.RESET().Lowered())
                 {
@@ -295,22 +291,11 @@ namespace EightBit
 
         private static byte ClearFlag(byte f, StatusBits flag, int condition) => ClearFlag(f, (byte)flag, condition);
 
-        private static byte ClearFlag(byte f, StatusBits flag, bool condition) => ClearFlag(f, (byte)flag, condition);
+        private static byte AdjustSign(byte input, byte value) => SetFlag(input, StatusBits.SF, value & (byte)StatusBits.SF);
 
-        private static byte AdjustSign(byte input, byte value)
+        private static byte AdjustZero(byte input, byte value) => ClearFlag(input, StatusBits.ZF, value);
-        {
-            return SetFlag(input, StatusBits.SF, value & (byte)StatusBits.SF);
-        }
 
-        private static byte AdjustZero(byte input, byte value)
+        private static byte AdjustParity(byte input, byte value) => SetFlag(input, StatusBits.PF, EvenParity(value));
-        {
-            return ClearFlag(input, StatusBits.ZF, value);
-        }
-
-        private static byte AdjustParity(byte input, byte value)
-        {
-            return SetFlag(input, StatusBits.PF, EvenParity(value));
-        }
 
         private static byte AdjustSZ(byte input, byte value)
         {
@@ -342,15 +327,9 @@ namespace EightBit
             return AdjustXY(input, value);
         }
 
-        private static byte AdjustHalfCarryAdd(byte input, byte before, byte value, int calculation)
+        private static byte AdjustHalfCarryAdd(byte input, byte before, byte value, int calculation) => SetFlag(input, StatusBits.HC, CalculateHalfCarryAdd(before, value, calculation));
-        {
-            return SetFlag(input, StatusBits.HC, CalculateHalfCarryAdd(before, value, calculation));
-        }
 
-        private static byte AdjustHalfCarrySub(byte input, byte before, byte value, int calculation)
+        private static byte AdjustHalfCarrySub(byte input, byte before, byte value, int calculation) => SetFlag(input, StatusBits.HC, CalculateHalfCarrySub(before, value, calculation));
-        {
-            return SetFlag(input, StatusBits.HC, CalculateHalfCarrySub(before, value, calculation));
-        }
 
         private static byte AdjustOverflowAdd(byte input, int beforeNegative, int valueNegative, int afterNegative)
         {
@@ -358,10 +337,7 @@ namespace EightBit
             return SetFlag(input, StatusBits.VF, overflow);
         }
 
-        private static byte AdjustOverflowAdd(byte input, byte before, byte value, byte calculation)
+        private static byte AdjustOverflowAdd(byte input, byte before, byte value, byte calculation) => AdjustOverflowAdd(input, before & (byte)StatusBits.SF, value & (byte)StatusBits.SF, calculation & (byte)StatusBits.SF);
-        {
-            return AdjustOverflowAdd(input, before & (byte)StatusBits.SF, value & (byte)StatusBits.SF, calculation & (byte)StatusBits.SF);
-        }
 
         private static byte AdjustOverflowSub(byte input, int beforeNegative, int valueNegative, int afterNegative)
         {
@@ -369,20 +345,11 @@ namespace EightBit
             return SetFlag(input, StatusBits.VF, overflow);
         }
 
-        private static byte AdjustOverflowSub(byte input, byte before, byte value, byte calculation)
+        private static byte AdjustOverflowSub(byte input, byte before, byte value, byte calculation) => AdjustOverflowSub(input, before & (byte)StatusBits.SF, value & (byte)StatusBits.SF, calculation & (byte)StatusBits.SF);
-        {
-            return AdjustOverflowSub(input, before & (byte)StatusBits.SF, value & (byte)StatusBits.SF, calculation & (byte)StatusBits.SF);
-        }
 
-        private static byte RES(int n, byte operand)
+        private static byte RES(int n, byte operand) => (byte)(operand & ~(1 << n));
-        {
-            return (byte)(operand & ~(1 << n));
-        }
 
-        private static byte SET(int n, byte operand)
+        private static byte SET(int n, byte operand) => (byte)(operand | (1 << n));
-        {
-            return (byte)(operand | (1 << n));
-        }
 
         private void DisableInterrupts() => this.IFF1 = this.IFF2 = false;
 
@@ -531,7 +498,6 @@ namespace EightBit
 
         private void ExecuteCB(int x, int y, int z)
         {
-            var memoryY = y == 6;
             var memoryZ = z == 6;
             var indirect = (!this.displaced && memoryZ) || this.displaced;
             var direct = !indirect;
@@ -620,8 +586,6 @@ namespace EightBit
 
         private void ExecuteED(int x, int y, int z, int p, int q)
         {
-            var memoryY = y == 6;
-            var memoryZ = z == 6;
             switch (x)
             {
                 case 0:
@@ -647,14 +611,7 @@ namespace EightBit
                         case 1: // Output to port with 16-bit address
                             this.MEMPTR.Word = this.Bus.Address.Word = this.BC.Word;
                             this.MEMPTR.Word++;
-                            if (y != 6)
+                            this.Bus.Data = y != 6 ? this.R(y) : (byte)0;
-                            {
-                                this.Bus.Data = this.R(y); // OUT (C),r[y]
-                            }
-                            else
-                            {
-                                this.Bus.Data = 0; // OUT (C),0
-                            }
 
                             this.WritePort();
                             this.Tick(12);
@@ -1132,7 +1089,7 @@ namespace EightBit
                 case 1: // 8-bit loading
                     if (!(memoryZ && memoryY))
                     {
-                        bool normal = true;
+                        var normal = true;
                         if (this.displaced)
                         {
                             if (memoryZ || memoryY)
@@ -1365,7 +1322,7 @@ namespace EightBit
                                             this.Execute(this.FetchByte());
                                             break;
                                         case 3: // FD prefix
-                                            this.displaced = this.prefixFD = true;
+                                            this.displaced = true;
                                             this.LowerM1();
                                             this.Execute(this.FetchByte());
                                             break;
@@ -2038,10 +1995,7 @@ namespace EightBit
             ++this.MEMPTR.Low;
         }
 
-        private void WritePort()
+        private void WritePort() => this.ports.Write(this.Bus.Address.Low, this.Bus.Data);
-        {
-            this.ports.Write(this.Bus.Address.Low, this.Bus.Data);
-        }
 
         private byte ReadPort(byte port)
         {
@@ -2050,9 +2004,6 @@ namespace EightBit
             return this.ReadPort();
         }
 
-        private byte ReadPort()
+        private byte ReadPort() => this.Bus.Data = this.ports.Read(this.Bus.Address.Low);
-        {
-            return this.Bus.Data = this.ports.Read(this.Bus.Address.Low);
-        }
     }
 }