implemented Clrw instruction

Co-authored-by: Darkress <30271678+DarkressX@users.noreply.github.com>
Reviewed-on: darkress/pic16f84-sim#14

de/darkress/pic16f84sim/Main.java

@@ -12,10 +12,8 @@ class Main
     public static void main(String[] args) {
 
         ArrayList<Command> program = new ArrayList<>();
-        int input1 = 0x27FF;
-        program.add(CommandDecoder.decode(0x3011)); //Write 0x11 to W
-        Memory.setRegister(0x14, 0x01);
-        program.add(CommandDecoder.decode(0x0A94)); //Write 0x11 to W
+        Memory.workingRegister = 0x10;
+        program.add(CommandDecoder.decode(0x123)); //Write 0x11 to W
         for(int i = 0; i < program.size(); i++)
         {
             program.get(ProgramCounter.getPc()).execute();

de/darkress/pic16f84sim/commands/Clrw.java

@@ -0,0 +1,18 @@
+package de.darkress.pic16f84sim.commands;
+
+import de.darkress.pic16f84sim.microcontroller.Memory;
+import de.darkress.pic16f84sim.microcontroller.ProgramCounter;
+
+public class Clrw extends FileRegisterCommandUtils implements Command
+{
+    @Override
+    public void execute()
+    {
+        final int result = 0;
+
+        checkZeroBit(result);
+
+        Memory.workingRegister = result;
+        ProgramCounter.incPC();
+    }
+}

de/darkress/pic16f84sim/commands/Incfsz.java

@@ -0,0 +1,33 @@
+package de.darkress.pic16f84sim.commands;
+
+import de.darkress.pic16f84sim.microcontroller.Memory;
+import de.darkress.pic16f84sim.microcontroller.ProgramCounter;
+
+public class Incfsz extends FileRegisterCommandUtils implements Command
+{
+    private final int address;
+    private final boolean destinationBit;
+
+    public Incfsz(int input)
+    {
+        address = input & 0x007F;
+        destinationBit = checkDestinationBit(input);
+    }
+
+    @Override
+    public void execute()
+    {
+        int result = Memory.getRegister(address) + 1;
+
+        checkZeroBit(result);
+
+        writeToDestination(destinationBit, address, result % 256);
+
+        if((result % 256) == 0)
+        {
+            Nop nop = new Nop();
+            nop.execute();
+        }
+        ProgramCounter.incPC();
+    }
+}

de/darkress/pic16f84sim/decoder/CommandDecoder.java

@@ -21,8 +21,7 @@ public class CommandDecoder
             case 0xA00:
                 return new Incf(input);
             case 0xF00:
-                //incfsz();
-                break;
+                return new Incfsz(input);
             case 0x400:
                 //iorwf();
                 break;
@@ -58,8 +57,7 @@ public class CommandDecoder
                 //clrf();
                 break;
             case 0x100:
-                //clrw();
-                break;
+                return new Clrw();
             case 0x80:
                 //movwf();
                 break;