       enableInterrupt(encoderPin1, interruptFunctionLeft, RISING);
       enableInterrupt(encoderPin2, interruptFunctionRight, RISING);
     }
-    if (pixyIsReporting) {
+    if (pixyIsReporting && pixyPtr != NULL) {
       numPixyBlocks = pixyPtr->getBlocks();
       // Only send Pixy data if a block was found.
 

void interruptFunctionRight() {
  interruptCountRight++;
}

/* Pixy Support */
Pixy* pixyPtr = NULL;

      break;
    case PIXY_CONFIG:
      if (argv[0] == PIXY_INIT) {
        if (pixyPtr == NULL) {
          pixyPtr = new Pixy();
          pixyPtr->init();
        }
        // mark pins as Pixy so they are ignore in non Pixy data requests
        setPinModeCallback(PIN_PIXY_MOSI, PIXY);
        setPinModeCallback(PIN_PIXY_MISO, PIXY);
