Added Xorwf Instruction (#24)

Co-authored-by: Darkress <30271678+DarkressX@users.noreply.github.com>
Reviewed-on: darkress/pic16f84-sim#24

de/darkress/pic16f84sim/Main.java

@@ -14,7 +14,7 @@ class Main
         ArrayList<Command> program = new ArrayList<>();
         Memory.workingRegister = 0x01;
         Memory.setRegister(0x14, 0xA5); //240 << 224
-        program.add(CommandDecoder.decode(0x0E94));
+        program.add(CommandDecoder.decode(0x0694));
         for(int i = 0; i < program.size(); i++)
         {
             program.get(ProgramCounter.getPc()).execute();

de/darkress/pic16f84sim/commands/Xorwf.java

@@ -0,0 +1,27 @@
+package de.darkress.pic16f84sim.commands;
+
+import de.darkress.pic16f84sim.microcontroller.Memory;
+import de.darkress.pic16f84sim.microcontroller.ProgramCounter;
+
+public class Xorwf extends FileRegisterCommandUtils implements Command
+{
+    private final int address;
+    private final boolean destinationBit;
+
+    public Xorwf(int input)
+    {
+        address = input & 0x007F;
+        destinationBit = checkDestinationBit(input);
+    }
+
+    @Override
+    public void execute()
+    {
+        int result = Memory.getRegister(address) ^ Memory.workingRegister;
+
+        checkZeroBit(result);
+
+        writeToDestination(destinationBit, address, result);
+        ProgramCounter.incPC();
+    }
+}

de/darkress/pic16f84sim/decoder/CommandDecoder.java

@@ -35,8 +35,7 @@ public class CommandDecoder
             case 0xE00:
                 return new Swapf(input);
             case 0x600:
-                //xorwf();
-                break;
+                return new Xorwf(input);
             case 0x3900:
                 return new Andlw(input);
             case 0x3800: