Release 0.7.0.9

---------------
PR #62: clandrew - Add --exec-breakpoint command line option for adding a breakpoint on launch.
Fixed the RTC not raising alerts correctly.
Fixed stack overflow issue with 6502 processor.

Main/Devices/RTC.cs

@@ -201,13 +201,19 @@ public override byte ReadByte(int Address)
                 data[13] = 0;
                 return value;
             }
-            return base.ReadByte(Address);
+            return data[Address];
         }
         public override void WriteByte(int Address, byte Value)
         {
             // Allow writing to the control register
             switch (Address)
             {
+                case 1:
+                case 3:
+                case 5:
+                case 7:
+                    data[Address] = Value;
+                    break;
                 case 0xB:
                     // reset the value of the hi-res periodic timer - the watch dog is ignored
                     freq = 0.0305175f * (1 << (Value & 0xF)); // ms
@@ -216,15 +222,16 @@ public override void WriteByte(int Address, byte Value)
                         freq = 200;
                     }
                     data[0xB] = (byte)(Value & 0x7F);
+                    periodicTimer.Interval = freq;
                     break;
                 case 0xC:
                     // Enables Register
                     data[0xC] = (byte)(Value & 0xF);
                     isAlarmEnabled = (Value & 8) != 0;
                     isPeriodicEnabled = (Value & 4) != 0;
-                    if (periodicTimer != null && !isPeriodicEnabled)
+                    if (periodicTimer != null) 
                     {
-                        periodicTimer.Enabled = false;
+                        periodicTimer.Enabled = isPeriodicEnabled;
                     }
                     if (isPeriodicEnabled)
                     {
@@ -253,12 +260,12 @@ public override void WriteByte(int Address, byte Value)
                     }
                     data[0xE] = (byte)(Value & 0xF);
                     break;
-
-
-            }
-            if (is_UTI_Set && (Address < 0xB || Address == 0xF))
-            {
-                tempValues[Address] = Value;
+                default:
+                    if (is_UTI_Set)
+                    {
+                        tempValues[Address] = Value;
+                    }
+                    break;
             }
         }
     }

Main/MemoryLocations/MemoryMap_Page00.cs

@@ -199,7 +199,7 @@ public static partial class MemoryMap
 
 
         public const int VECTOR_ECOP = 0x00FFF4; // 2 Bytes Emulation mode interrupt handler
-        public const int VECTOR_EBRK = 0x00FFF6; // 2 Bytes Emulation mode interrupt handler
+        public const int VECTOR_EBRK = 0x00FFFE; // 2 Bytes Emulation mode interrupt handler
         public const int VECTOR_EABORT = 0x00FFF8; // 2 Bytes Emulation mode interrupt handler
         public const int VECTOR_ENMI = 0x00FFFA; // 2 Bytes Emulation mode interrupt handler
         public const int VECTOR_ERESET = 0x00FFFC; // 2 Bytes Emulation mode interrupt handler

Main/Processor/CPU.cs

@@ -62,6 +62,7 @@ public partial class CPU
 
         public const int DefaultStackValueNative = 0xd6ff;
         public const int DefaultStackValueEmulation = 0x01ff;
+        private bool is6502 = false;
 
         public int ClockSpeed
         {
@@ -101,6 +102,7 @@ public CPU(MemoryManager mm, int clock, bool is6502)
             Operations operations = new Operations(this);
             operations.SimulatorCommand += Operations_SimulatorCommand;
             opcodes = new OpcodeList(operations, this, is6502);
+            this.is6502 = is6502;
             Flags.Emulation = true;
         }
 
@@ -269,7 +271,7 @@ public int ReadSignature(int length, int pc)
         }
 
         /// <summary>
-        /// Clock cycles used for performance counte This will be periodically reset to zero
+        /// Clock cycles used for performance counter. This will be periodically reset to zero
         /// as the throttling routine adjusts the system performance. 
         /// </summary>
         public int CycleCounter
@@ -323,6 +325,11 @@ public void Push(int value, int bytes)
                 throw new Exception("bytes must be between 1 and 3. Got " + bytes.ToString());
 
             Stack.Value -= bytes;
+            // Check if the stack has overflowed
+            if (is6502 && (Stack.Value & 0xFF00 ) != 0x100)
+            {
+                Stack.Value = 0x100 + (Stack.Value & 0xFF);
+            } 
             MemMgr.Write(Stack.Value + 1, value, bytes);
         }
 
@@ -339,7 +346,9 @@ public void Push(Register Reg)
         public int Pull(int bytes)
         {
             if (bytes < 1 || bytes > 3)
+            {
                 throw new Exception("bytes must be between 1 and 3. got " + bytes.ToString());
+            }
 
             int ret = MemMgr.Read(Stack.Value + 1, bytes);
 

Main/Properties/AssemblyInfo.cs

@@ -32,5 +32,5 @@
 // You can specify all the values or you can default the Build and Revision Numbers
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("0.7.0.8")]
-[assembly: AssemblyFileVersion("0.7.0.8")]
+[assembly: AssemblyVersion("0.7.0.9")]
+[assembly: AssemblyFileVersion("0.7.0.9")]

Main/UI/CPUWindow.cs

@@ -797,7 +797,7 @@ private bool ShouldBreakExecution(int nextPC, ref int breakAddress)
                 return true;
             }
 
-            if (kernel.CPU.CurrentOpcode.Value == 0)
+            if (kernel.CPU.CurrentOpcode.Value == 0 && nextPC == 0)
             {
                 breakAddress = 0;
                 return true;

Release Notes.txt

@@ -1,8 +1,9 @@
-Release 0.7.0.8
+Release 0.7.0.9
 ---------------
-PR #61: clandrew - Don't let the user "add watch" on an invisible element
-PR #60: clandrew - Fix problem where new breakpoints don't "take effect" until after you pause the debugger
-PR #59: clandrew - Show debugger's breakpoint address instead of hardcoded FFFFFFFF
+PR #62: clandrew - Add --exec-breakpoint command line option for adding a breakpoint on launch.
+Fixed the RTC not raising alerts correctly.
+Fixed stack overflow issue with 6502 processor.
+
 ** TODO: Users can now modify the CPU registers when in debug mode. The registers have a white background when editable.
 ** TODO: Implemented the various cursor modes and rates.
 ** TODO: Implement an IEC interface to connect via USB to XUM1541 (try using the SerialPort class?).
@@ -15,6 +16,13 @@ PR #59: clandrew - Show debugger's breakpoint address instead of hardcoded FFFFF
 ** TODO: Saving basic files to emulated SD card often doesn't work or crashes the emulator.
 ** TODO: Support two joysticks and allow for multiple joystick buttons
 
+Release 0.7.0.8
+---------------
+PR #61: clandrew - Don't let the user "add watch" on an invisible element
+PR #60: clandrew - Fix problem where new breakpoints don't "take effect" until after you pause the debugger
+PR #59: clandrew - Show debugger's breakpoint address instead of hardcoded FFFFFFFF
+
+
 Release 0.7.0.7
 ---------------
 Fixed typo in CPU Window - Address was mis-spelled.