implemented bcfInstruction

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

de/darkress/pic16f84sim/Main.java

@@ -12,9 +12,9 @@ class Main
     public static void main(String[] args) {
 
         ArrayList<Command> program = new ArrayList<>();
-        Memory.workingRegister = 0x1A;
+        Memory.workingRegister = 0x01;
-        Memory.setRegister(0x14, 0x1B);
+        Memory.setRegister(0x14, 0xA5); //240 << 224
-        program.add(CommandDecoder.decode(0x0094));
+        program.add(CommandDecoder.decode(0x1114));
         for(int i = 0; i < program.size(); i++)
         {
             program.get(ProgramCounter.getPc()).execute();

de/darkress/pic16f84sim/commands/Bcf.java

@@ -0,0 +1,26 @@
+package de.darkress.pic16f84sim.commands;
+
+import de.darkress.pic16f84sim.microcontroller.Memory;
+import de.darkress.pic16f84sim.microcontroller.ProgramCounter;
+
+public class Bcf extends BitOrientedCommandUtils implements Command
+{
+    private final int address;
+    private int bitPlacement;
+
+    public Bcf(int input)
+    {
+        address = input & 0x007F;
+        bitPlacement = checkBitPlacement(input);
+    }
+
+    @Override
+    public void execute()
+    {
+        int result = Memory.getRegister(address);
+        result &= ~(1 << bitPlacement); //Mask n-th bit with 0
+
+        Memory.setRegister(address, result);
+        ProgramCounter.incPC();
+    }
+}

de/darkress/pic16f84sim/commands/BitOrientedCommandUtils.java

@@ -0,0 +1,11 @@
+package de.darkress.pic16f84sim.commands;
+
+import de.darkress.pic16f84sim.microcontroller.Memory;
+
+public class BitOrientedCommandUtils
+{
+    protected int checkBitPlacement(int input)
+    {
+        return ((input & 0x0380) >>7);
+    }
+}

de/darkress/pic16f84sim/commands/Decfsz.java

@@ -26,7 +26,7 @@ public class Decfsz extends FileRegisterCommandUtils implements Command
         if((result % 256) == 0)
         {
             Nop nop = new Nop();
-            nop.execute();
+            nop.execute(); // TODO: What happens if an interrupt gets triggered during the nop execution?
         }
         ProgramCounter.incPC();
     }

de/darkress/pic16f84sim/commands/Incfsz.java

@@ -26,7 +26,7 @@ public class Incfsz extends FileRegisterCommandUtils implements Command
         if((result % 256) == 0)
         {
             Nop nop = new Nop();
-            nop.execute();
+            nop.execute(); // TODO: What happens if an interrupt gets triggered during the nop execution?
         }
         ProgramCounter.incPC();
     }

de/darkress/pic16f84sim/commands/Rlf.java

@@ -0,0 +1,35 @@
+package de.darkress.pic16f84sim.commands;
+
+import de.darkress.pic16f84sim.microcontroller.Memory;
+import de.darkress.pic16f84sim.microcontroller.ProgramCounter;
+
+public class Rlf extends FileRegisterCommandUtils implements Command
+{
+    private final int address;
+    private final boolean destinationBit;
+
+    public Rlf(int input)
+    {
+        address = input & 0x007F;
+        destinationBit = checkDestinationBit(input);
+    }
+
+    @Override
+    public void execute()
+    {
+        int register = Memory.getRegister(address);
+        int newCarry = register >>7;
+        int oldCarry = Memory.getCarryBit();
+        register = ((register <<1) + oldCarry) & 0xFF;
+
+        if(newCarry == 1)
+        {
+            Memory.setCarryBit();
+        } else if(newCarry == 0){
+            Memory.clearCarryBit();
+        }
+
+        writeToDestination(destinationBit, address, register);
+        ProgramCounter.incPC();
+    }
+}

de/darkress/pic16f84sim/commands/Rrf.java

@@ -0,0 +1,35 @@
+package de.darkress.pic16f84sim.commands;
+
+import de.darkress.pic16f84sim.microcontroller.Memory;
+import de.darkress.pic16f84sim.microcontroller.ProgramCounter;
+
+public class Rrf extends FileRegisterCommandUtils implements Command
+{
+    private final int address;
+    private final boolean destinationBit;
+
+    public Rrf(int input)
+    {
+        address = input & 0x007F;
+        destinationBit = checkDestinationBit(input);
+    }
+
+    @Override
+    public void execute()
+    {
+        int register = Memory.getRegister(address);
+        int newCarry = register & 0x01;
+        int oldCarry = Memory.getCarryBit();
+        register = (oldCarry << 7) + (register >>1);
+
+        if(newCarry == 1)
+        {
+            Memory.setCarryBit();
+        } else if(newCarry == 0){
+            Memory.clearCarryBit();
+        }
+
+        writeToDestination(destinationBit, address, register);
+        ProgramCounter.incPC();
+    }
+}

de/darkress/pic16f84sim/commands/Subwf.java

@@ -0,0 +1,49 @@
+package de.darkress.pic16f84sim.commands;
+
+import de.darkress.pic16f84sim.microcontroller.Memory;
+import de.darkress.pic16f84sim.microcontroller.ProgramCounter;
+
+public class Subwf extends FileRegisterCommandUtils implements Command
+{
+    private final int address;
+    private final boolean destinationBit;
+
+    public Subwf(int input)
+    {
+        address = input & 0x007F;
+        destinationBit = checkDestinationBit(input);
+    }
+
+    @Override
+    protected void checkCarryBit(int result)
+    {
+        if(result <= 255){
+            Memory.clearCarryBit();
+        } else{
+            Memory.setCarryBit();
+        }
+    }
+
+    @Override
+    protected void checkDigitCarryBit(int literal)
+    {
+        if(((literal & 0x0F) - (Memory.workingRegister & 0x0F)) < 0){
+            Memory.clearDigitCarryBit();
+        } else{
+            Memory.setDigitCarryBit();
+        }
+    }
+
+    @Override
+    public void execute()
+    {
+        int result = Memory.getRegister(address) - Memory.workingRegister + 256;
+
+        checkZeroBit(result);
+        checkCarryBit(result);
+        checkDigitCarryBit(Memory.getRegister(address));
+
+        writeToDestination(destinationBit, address, result % 256);
+        ProgramCounter.incPC();
+    }
+}

de/darkress/pic16f84sim/commands/Swapf.java

@@ -0,0 +1,27 @@
+package de.darkress.pic16f84sim.commands;
+
+import de.darkress.pic16f84sim.microcontroller.Memory;
+import de.darkress.pic16f84sim.microcontroller.ProgramCounter;
+
+public class Swapf extends FileRegisterCommandUtils implements Command
+{
+    private final int address;
+    private final boolean destinationBit;
+
+    public Swapf(int input)
+    {
+        address = input & 0x007F;
+        destinationBit = checkDestinationBit(input);
+    }
+
+    @Override
+    public void execute()
+    {
+        int result = (Memory.getRegister(address) <<4) & 0xF0;
+        int tmp = Memory.getRegister(address) >>4;
+        result += tmp;
+
+        writeToDestination(destinationBit, address, result);
+        ProgramCounter.incPC();
+    }
+}

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

@@ -27,20 +27,15 @@ public class CommandDecoder
             case 0x800:
                 return new Movf(input);
             case 0xD00:
-                //rlf();
+                return new Rlf(input);
-                break;
             case 0xC00:
-                //rrf();
+                return new Rrf(input);
-                break;
             case 0x200:
-                //subwf();
+                return new Subwf(input);
-                break;
             case 0xE00:
-                //swapf();
+                return new Swapf(input);
-                break;
             case 0x600:
-                //xorwf();
+                return new Xorwf(input);
-                break;
             case 0x3900:
                 return new Andlw(input);
             case 0x3800:
@@ -62,8 +57,7 @@ public class CommandDecoder
         switch(input & 0x3C00)
         {
             case 0x1000:
-                //bcf();
+                return new Bcf(input);
-                break;
             case 0x1400:
                 //bsf();
                 break;

de/darkress/pic16f84sim/microcontroller/Memory.java

@@ -153,9 +153,13 @@ public class Memory
         memory[0x03] &= 0xFD;
     }
 
-    public static boolean getCarryBit()
+    public static int getCarryBit()
     {
-        return (memory[0x03] & 0x01) == 0x01;
+        if((memory[0x03] & 0x01) == 0x01)
+        {
+            return 1;
+        }
+        else return 0;
     }
 
     public static void setCarryBit()