diff --git a/src/main/java/fabrik/simulator/pic16f84/IOPorts.java b/src/main/java/fabrik/simulator/pic16f84/IOPorts.java
index b005550..388ba16 100644
--- a/src/main/java/fabrik/simulator/pic16f84/IOPorts.java
+++ b/src/main/java/fabrik/simulator/pic16f84/IOPorts.java
@@ -53,7 +53,7 @@ public class IOPorts {
     }
 
     private static void refreshPorts() {
-        DataRegister.setDirectRegister(PORTA, ((~((~dataLatch[A])&0xFF | trisLatch[A])) | (trisLatch[A] & DataRegister.getDirectRegister(PORTA))) & 0x1F);
+        DataRegister.setDirectRegister(PORTA, ((~((~dataLatch[A])&0xFF | trisLatch[A])) | (trisLatch[A] & DataRegister.getDirectRegister(PORTA))) & 0xFF);
         DataRegister.setDirectRegister(PORTB, ((~((~dataLatch[B])&0xFF | trisLatch[B])) | (trisLatch[B] & DataRegister.getDirectRegister(PORTB))) & 0xFF);
         DataRegister.setDirectRegister(TRISA, trisLatch[A]);
         DataRegister.setDirectRegister(TRISB, trisLatch[B]);