'Set terminal status line: Request To Send.'

def _update_rts_state(self):

    if (not self.is_open):
        raise portNotOpenError
    if self.logger:
        self.logger.info('set    RTS    to    {}'.format(('active' if self._rts_state else 'inactive')))
    if self._rts_state:
        self.rfc2217_set_control(SET_CONTROL_RTS_ON)
    else:
        self.rfc2217_set_control(SET_CONTROL_RTS_OFF)
