.. _auto_set_state_led_off:

set_state_led_off (Auto Mode)
------------------------------------------
This section explains how to use :ref:`set_state_led_off <set_state_led_off>` during **Auto** operations.
This function turns **off** the robot’s State LED completely.  
It is often used when you want to disable LED indication temporarily during maintenance or quiet operation.

Available in Auto mode only, on controller v3.4 or later. In other modes, or on an older controller, the function returns false. The mode check uses the value returned by :ref:`get_robot_mode <get_robot_mode>`.

**Typical usage**

- Turn off LED illumination during diagnostics.
- Use when LED light may interfere with visual calibration or camera sensing.  
- Disable LED to indicate a “paused” or “standby” condition.

**Example**

The example obtains control authority and sets Auto mode before the LED calls, because the LED functions are refused in other modes.

.. code-block:: cpp

   #include <atomic>
   #include <chrono>
   #include <cstdio>
   #include <thread>

   std::atomic<bool> g_bHasControlAuthority(false);

   void OnMonitoringAccessControlCB(const MONITORING_ACCESS_CONTROL eAccess)
   {
       if (eAccess == MONITORING_ACCESS_CONTROL_GRANT)
           g_bHasControlAuthority = true;
   }

   drfl.set_on_monitoring_access_control(OnMonitoringAccessControlCB);
   if (!drfl.open_connection("192.168.137.100")) return 1;
   drfl.manage_access_control(MANAGE_ACCESS_CONTROL_FORCE_REQUEST);
   while (!g_bHasControlAuthority)
       std::this_thread::sleep_for(std::chrono::milliseconds(100));

   // The LED functions are refused unless Auto mode is set
   if (!drfl.set_robot_mode(ROBOT_MODE_AUTONOMOUS)) return 1;

   if (!drfl.set_state_led_off()) {
       printf("[ERROR] Failed to turn off the State LED.\n");
       return 1;
   }
   printf("[LED] State LED has been turned off.\n");

   std::this_thread::sleep_for(std::chrono::seconds(3));
   if (drfl.state_led_reset())  // Restore LED afterward
       printf("[LED] LED reset to default state.\n");
   else
       printf("[ERROR] Failed to reset LED state.\n");

This function **disables all LED output**, allowing tasks to be performed without LED distraction or ambient light interference.

.. Note::

   A return of true does not confirm that the LED changed.

**Tips**

- Use to indicate a **standby** or **inactive** state during pauses.
- Combine with :ref:`state_led_reset <state_led_reset>` to restore LED behavior after maintenance.  
- Helpful when performing **camera calibration** or light-sensitive operations.