def open(self, baudrate=BAUDRATE, no_reader_thread=False):
        """
        Opens the device.

        :param baudrate: baudrate to use with the device
        :type baudrate: int
        :param no_reader_thread: whether or not to automatically start the
                                 reader thread.
        :type no_reader_thread: bool

        :raises: :py:class:`~alarmdecoder.util.NoDeviceError`
        """
        # Set up the defaults
        if baudrate is None:
            baudrate = SerialDevice.BAUDRATE

        if self._port is None:
            raise NoDeviceError('No device interface specified.')

        self._read_thread = Device.ReadThread(self)

        # Open the device and start up the reader thread.
        try:
            self._device.port = self._port
            self._device.open()
            # NOTE: Setting the baudrate before opening the
            #       port caused issues with Moschip 7840/7820
            #       USB Serial Driver converter. (mos7840)
            #
            #       Moving it to this point seems to resolve
            #       all issues with it.
            self._device.baudrate = baudrate

        except (serial.SerialException, ValueError, OSError) as err:
            raise NoDeviceError('Error opening device on {0}.'.format(self._port), err)

        else:
            self._running = True
            self.on_open()

            if not no_reader_thread:
                self._read_thread.start()

        return self