         pixels.show();
         break;
       default:
+#ifdef ENABLE_MOTOR_FUNCTIONS
         // Unknown command, stop the motors.
         for (int i = 0; i < 3; i++) {
           ST[i].motor(0);
         }
+#endif
         pixels.setSolidColour(0, 255, 50);
         pixels.show();
         break;

// Called on I2C data request
void requestEvent() {
  byte data[] = {(byte)((pos_a & 0xff00) >> 8),
                    (byte)(pos_a & 0xff),
                    (byte)((pos_b & 0xff00) >> 8),
                    (byte)(pos_b & 0xff),
                    (byte)((pos_c & 0xff00) >> 8),
                    (byte)(pos_c & 0xff)
                   };
  Serial.println("a");
  Serial.println(data[0]);
  Serial.println("b");

  PCICR |= (1 << PCIE0);
  // Un-mask all pins
  PCMSK0 = 63;
  // Enable interrupts
  sei();

#ifdef ENABLE_MOTOR_FUNCTIONS
  for (int i = 0; i < 3; i++) {
    ST[i].motor(0);
  }
#endif
  pixels.setSolidColour(170, 255, 60);
  pixels.show();
}
