Added control pad to Kempston interface

Core/Io/IO_Bus.cs

@@ -6,7 +6,8 @@ namespace Core.Io
 {
     public class IO_Bus
     {
-        public byte BorderColorIndex { get;  set; } = 7;
+        public byte BorderColourIndex { get;  set; } = 7;
+        public byte KempstonState { get; set; } = 0x00;
         public bool BeeperState { get; private set; } = false;
         public byte[] KeyboardRows = new byte[8] { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
         TapManager _tapManager = new TapManager();
@@ -18,14 +19,13 @@ namespace Core.Io
 
         public byte ReadPort(ushort portAddress)
         {
-            // The Spectrum ULA responds to any even port address (where the lowest bit is 0)
+            //ULA responds to any even port address (where the lowest bit is 0)
             if ((portAddress & 0x01) == 0) //Port 0xFE)
             {
-                byte highByte = (byte)(portAddress >> 8); // The B register!
+                byte highByte = (byte)(portAddress >> 8); // The B register
                 byte result = 0xFF; // Start assuming no keys are pressed
 
-                // The ROM pulls a specific bit low (0) in the high byte to request a row.
+                
-                // Sometimes it pulls multiple bits low to scan multiple rows at once, so we AND the results.
                 if ((highByte & 0x01) == 0) result &= KeyboardRows[0]; // 0xFE: CAPS, Z, X, C, V
                 if ((highByte & 0x02) == 0) result &= KeyboardRows[1]; // 0xFD: A, S, D, F, G
                 if ((highByte & 0x04) == 0) result &= KeyboardRows[2]; // 0xFB: Q, W, E, R, T
@@ -37,8 +37,6 @@ namespace Core.Io
                 if (_tapManager.EarBit) result |= 0x40; // Set Bit 6 high
                     else result &= 0xBF; // Set Bit 6 low
                 
-
-                //return result;
                 //The top 3 bits (5, 6, 7) are unused by the keyboard and usually return 1 on a real Spectrum
                 return (byte)(result | 0xA0);
             }
@@ -46,7 +44,7 @@ namespace Core.Io
             //Kempston Joystick Port
             if ((portAddress & 0xFF) == 0x1F)
             {
-                return 0x00; // 0x00 means no joystick connected/no buttons pressed
+                return KempstonState; 
             }
 
             //Return 0xFF for unhandled ports
@@ -59,7 +57,7 @@ namespace Core.Io
             if ((portAddress & 0x01) == 0)
             {
                 // The bottom 3 bits (0-2) define the border color
-                BorderColorIndex = (byte)(portValue & 0x07);
+                BorderColourIndex = (byte)(portValue & 0x07);
 
                 // Bit 4 controls the speaker
                 BeeperState = (portValue & 0x10) != 0;

Core/Io/ULA.cs

@@ -17,7 +17,7 @@ namespace Core.Io
         private int _ulaFrameCount = 0;
 
         // The hardware color palette belongs to the ULA, not the Windows Form!
-        private readonly int[] SpectrumColors = new int[]
+        private readonly int[] SpectrumColours = new int[]
         {
             unchecked((int)0xFF000000), unchecked((int)0xFF0000D7),
             unchecked((int)0xFFD70000), unchecked((int)0xFFD700D7),
@@ -59,7 +59,7 @@ namespace Core.Io
 
             // 2. Calculate our visual Y coordinate (0 to 255) for the bitmap array
             int renderY = scanline - 32;
-            int currentBorderColor = SpectrumColors[_simpleIoBus.BorderColorIndex];
+            int currentBorderColor = SpectrumColours[_simpleIoBus.BorderColourIndex];
 
             // --- Are we in the Top or Bottom Border? ---
             if (scanline < 64 || scanline > 255)
@@ -102,8 +102,8 @@ namespace Core.Io
                 int brightOffset = (attr & 0x40) != 0 ? 8 : 0;
                 bool isFlashSet = (attr & 0x80) != 0;
 
-                int inkColor = SpectrumColors[ink + brightOffset];
+                int inkColor = SpectrumColours[ink + brightOffset];
-                int paperColor = SpectrumColors[paper + brightOffset];
+                int paperColor = SpectrumColours[paper + brightOffset];
 
                 if (isFlashSet && invertFlashPhase)
                 {

Core/SpectrumMachine.cs

@@ -292,7 +292,7 @@ namespace Core
             // Cpu.InterruptMode = snaData[25]; 
 
             // THE BUG FIX: Restore the ULA Border Color!
-            IoBus.BorderColorIndex = snaData[26];
+            IoBus.BorderColourIndex = snaData[26];
 
             // 2. Load the 48K RAM Dump
             for (int i = 0; i < 49152; i++)
@@ -340,7 +340,7 @@ namespace Core
                 bw.Write(Cpu.AF.Low); bw.Write(Cpu.AF.High);
                 bw.Write((byte)(Cpu.SP & 0xFF)); bw.Write((byte)(Cpu.SP >> 8));
                 bw.Write((byte)Cpu.InterruptMode);
-                bw.Write(IoBus.BorderColorIndex);
+                bw.Write(IoBus.BorderColourIndex);
 
                 for (int i = 0x4000; i <= 0xFFFF; i++)
                 {

Desktop/Desktop.csproj

@@ -56,6 +56,7 @@
 
   <ItemGroup>
     <PackageReference Include="NAudio" Version="2.3.0" />
+    <PackageReference Include="Vortice.XInput" Version="3.8.3" />
   </ItemGroup>
 
   <ItemGroup>

Desktop/Form1.cs

@@ -1,7 +1,7 @@
-using Core; // <-- This gives us access to SpectrumMachine
+using Core;
 using Core.Io;
-using System.Diagnostics;
 using System.Drawing.Imaging;
+using Vortice.XInput;
 using System.Reflection;
 using System.Runtime.InteropServices;
 
@@ -17,12 +17,6 @@ namespace Desktop
         private Bitmap _screenBitmap = null!;
         private string _baseTitle = "";
 
-        // ====================================================================
-        // DEBUGGER PASS-THROUGHS
-        // ====================================================================
-        // The DebuggerForm still looks at Form1 for data. These properties act 
-        // as a bridge, instantly passing the request down to the actual engine!
-
         public ushort? Breakpoint
         {
             get => _machine?.Breakpoint;
@@ -84,11 +78,12 @@ namespace Desktop
 
         private void Machine_OnFrameReady(int[] pixels)
         {
-            // We must use BeginInvoke because the Machine is running on a background thread!
+            PollGamepad();
+
             this.BeginInvoke((System.Windows.Forms.MethodInvoker)delegate
             {
                 UpdateScreenBitmap(pixels);
-                this.Invalidate(); // Triggers OnPaint
+                this.Invalidate();
             });
         }
 
@@ -384,6 +379,35 @@ namespace Desktop
             _machine.Resume();
         }
 
+        //Control pad method       
+
+        private void PollGamepad()
+        {
+            // Only check Player 1 (Index 0)
+            if (XInput.GetState(0, out State state))
+            {
+                byte kempston = 0x00;
+                Gamepad gamepad = state.Gamepad;
+
+                // Map D-Pad to Kempston Bits
+                if ((gamepad.Buttons & GamepadButtons.DPadRight) != 0) kempston |= 0x01; // Bit 0
+                if ((gamepad.Buttons & GamepadButtons.DPadLeft) != 0) kempston |= 0x02; // Bit 1
+                if ((gamepad.Buttons & GamepadButtons.DPadDown) != 0) kempston |= 0x04; // Bit 2
+                if ((gamepad.Buttons & GamepadButtons.DPadUp) != 0) kempston |= 0x08; // Bit 3
+
+                // Map A Button (or whichever you prefer) to Fire
+                if ((gamepad.Buttons & GamepadButtons.A) != 0) kempston |= 0x10; // Bit 4
+
+                // Send the final byte down to the emulator core!
+                _machine.IoBus.KempstonState = kempston;
+            }
+            else
+            {
+                // Controller disconnected, zero it out
+                _machine.IoBus.KempstonState = 0x00;
+            }
+        }
+
 
     }
 }