Got main system and VDP working! There is a display!

Desktop/DebuggerForm.cs

@@ -27,11 +27,36 @@ namespace Desktop
             _mainForm = mainForm;
         }
 
+        private void CpuRun_Click(object sender, EventArgs e)
+        {
+            if (_mainForm.IsRunning)
+            {
+                // Stop the machine
+                _mainForm.StopEmulator();
+                CpuRun.Text = "CPU Run";
+
+                // Stop the live UI updates and do one final manual refresh
+                uiUpdateTimer.Stop();
+                UpdateDisplay();
+            }
+            else
+            {
+                // Start the machine
+                _mainForm.StartEmulator();
+                CpuRun.Text = "CPU Stop";
+
+                // Start the timer so the debugger screen updates automatically
+                // (Make sure your uiUpdateTimer Interval in the designer is set to something like 100ms)
+                uiUpdateTimer.Start();
+            }
+        }
+
         private void btnStep_Click(object sender, EventArgs e)
         {
             try
             {
-                _cpu.Step();
+                // Ask the main form to step the WHOLE machine, not just the Z80!
+                _mainForm.StepEmulator();
                 UpdateDisplay();
             }
             catch (Exception ex)
@@ -57,7 +82,7 @@ namespace Desktop
             UpdateDisplay();
         }
 
-        private void uiUpdateTimer_Tick(object sender, EventArgs e)
+        public void uiUpdateTimer_Tick(object sender, EventArgs e)
         {
             UpdateDisplay();
         }
@@ -180,6 +205,9 @@ namespace Desktop
                     case 0x02: mnemonic = "LD (BC), A"; break;
                     // --- 16-Bit Increments ---
                     case 0x03: mnemonic = "INC BC"; break;
+                    case 0x07:
+                        mnemonic = "RLCA";
+                        break;
                     case 0x08:
                         mnemonic = "EX AF, AF'";
                         break;