Added window scaling

Core/Cpu/Z80.cs

@@ -1303,6 +1303,35 @@ namespace Core.Cpu
 
             switch (extendedOpcode)
             {
+                case 0x40: // IN B, (C)
+                    {
+                        byte inVal40 = ReadPort(BC.Word);
+                        BC.High = inVal40;
+
+                        byte flags40 = (byte)(AF.Low & 0x01); // Preserve Carry
+                        if ((inVal40 & 0x80) != 0) flags40 |= 0x80; // S
+                        if (inVal40 == 0) flags40 |= 0x40;          // Z
+                        flags40 |= ParityTable[inVal40];            // P/V
+                        flags40 |= (byte)(inVal40 & 0x28);          // Undocumented bits 3 and 5
+
+                        AF.Low = flags40;
+                        return 12;
+                    }
+
+                case 0x50: // IN D, (C)
+                    {
+                        byte inVal50 = ReadPort(BC.Word);
+                        DE.High = inVal50;
+
+                        byte flags50 = (byte)(AF.Low & 0x01); // Preserve Carry
+                        if ((inVal50 & 0x80) != 0) flags50 |= 0x80; // S
+                        if (inVal50 == 0) flags50 |= 0x40;          // Z
+                        flags50 |= ParityTable[inVal50];            // P/V
+                        flags50 |= (byte)(inVal50 & 0x28);          // Undocumented bits 3 and 5
+
+                        AF.Low = flags50;
+                        return 12;
+                    }
                 case 0x41: // OUT (C), B
                     _simpleIoBus.WritePort(BC.Word, BC.High);
                     return 12;

Desktop/Desktop.csproj

@@ -15,6 +15,14 @@
 		<RuntimeIdentifier>win-x64</RuntimeIdentifier>
 		<StartupObject>Desktop.Program</StartupObject>
 		<AssemblyName>Parsons Master System</AssemblyName>
+		<ApplicationIcon>favicon.ico</ApplicationIcon>
+		<Title>Sega Master System EMulator 2026</Title>
+		<Version>0.9</Version>
+		<Authors>Marc Parsons</Authors>
+		<Company>Parsons Limited</Company>
+		<Description>Parsons Master System 2026</Description>
+		<Copyright>Copyright 2026 Marc Parsons</Copyright>
+		<PackageIcon>logo1.bmp</PackageIcon>
 	</PropertyGroup>
 
 	<ItemGroup>
@@ -103,6 +111,10 @@
 		<None Remove="ROMS\zexdoc.sms" />
 	</ItemGroup>
 
+	<ItemGroup>
+	  <Content Include="favicon.ico" />
+	</ItemGroup>
+
 	<ItemGroup>
 		<EmbeddedResource Include="ROMS\After Burner (UE) [!].sms">
 			<CopyToOutputDirectory>Never</CopyToOutputDirectory>
@@ -353,6 +365,13 @@
 		</EmbeddedResource>
 	</ItemGroup>
 
+	<ItemGroup>
+	  <None Include="..\logo1.bmp">
+	    <Pack>True</Pack>
+	    <PackagePath>\</PackagePath>
+	  </None>
+	</ItemGroup>
+
 	<ItemGroup>
 		<PackageReference Include="NAudio" Version="2.3.0" />
 		<PackageReference Include="Vortice.XInput" Version="3.8.3" />

Desktop/Form1.cs

@@ -53,7 +53,7 @@ namespace Desktop
 
             this.Text = $"Parsons Master System - {_currentRomName}";
 
-            // Safe to initialize hardware and files here!
+            this.BackColor = Color.Black;
             _machine = new SmsMachine();
             _audioPlayer = new NAudioPlayer();
             _machine.AudioProcessor.AudioDevice = _audioPlayer;
@@ -72,27 +72,37 @@ namespace Desktop
         }
         protected override void OnPaint(PaintEventArgs e)
         {
-            // Always call the base method so Windows can draw your MenuStrip!
             base.OnPaint(e);
 
-            // THE FIX: We MUST ensure the designer has actually built the menu strip before asking for its height!
             if (_screenBitmap != null && menuStrip1 != null)
             {
-                // 1. Set the rendering mode for perfect, chunky retro pixels!
+                // 1. Maintain perfect, chunky retro pixels
                 e.Graphics.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.NearestNeighbor;
                 e.Graphics.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.Half;
 
-                // 2. Calculate the drawing area. 
-                // We start drawing BELOW the MenuStrip so it doesn't get covered up.
+                // 2. Calculate the actual usable window space
                 int topOffset = menuStrip1.Height;
-                Rectangle renderArea = new Rectangle(
-                    0,
-                    topOffset,
-                    this.ClientSize.Width,
-                    this.ClientSize.Height - topOffset
-                );
+                int availableWidth = this.ClientSize.Width;
+                int availableHeight = this.ClientSize.Height - topOffset;
 
-                // 3. Blast the bitmap directly onto the graphics card buffer!
+                // 3. Calculate the maximum scale factor that fits perfectly
+                float scaleX = (float)availableWidth / 256f;
+                float scaleY = (float)availableHeight / 192f;
+
+                // Pick the smaller scale so the image never bleeds off the edge
+                float scale = Math.Min(scaleX, scaleY);
+
+                // 4. Calculate the new physical pixel dimensions
+                int newWidth = (int)(256 * scale);
+                int newHeight = (int)(192 * scale);
+
+                // 5. Center the image (Letterboxing / Pillarboxing)
+                int offsetX = (availableWidth - newWidth) / 2;
+                int offsetY = topOffset + ((availableHeight - newHeight) / 2);
+
+                Rectangle renderArea = new Rectangle(offsetX, offsetY, newWidth, newHeight);
+
+                // 6. Draw the scaled image
                 e.Graphics.DrawImage(_screenBitmap, renderArea);
             }
         }