code: public synchronized Boolean stop() {
          if (serialPort != null) {
              serialPort.removeEventListener(this);
          }
  
          if (!removeSerialPort()) {
              log.error("Failed to stop Firmata Library. Cannot close Serial Port.");
              log.error("Configuration is {}", configuration);
              return false;
          }
  
          started = false;
          return true;
      }
docs: Stops the Firmata library. If the library is already stopped, this will still attempt to stop anything
  that may still be lingering. Take note that many calls could eventually result in noticeable cpu usage.
  
  @return True if the library has stopped. False if there was an error stopping the library.