Required Shutdown Procedures for XBee Cellular Radio

It is not recommended to remove power from the XBee Cellular devices without performing a clean shutdown procedure first. Performing a shutdown allows the module to deregister from the cellular network and safely store operating parameters. Failure to shutdown properly has the potential to result in delays resuming network operation and in some rare instances may result in an unrecoverable module failure.

Choose from the approaches below to perform a shutdown.

Use the shutdown command

The recommended approach is to use the shutdown (ATSD) command, and wait for the OK to appear.  Once OK is reached, power may safely be removed.
If after 2 minutes, the radio is still not able to be fully shut down, the command will return ERROR.
To verify the state after the OK (or ERROR) has appeared, you may issue an ATAI, which will return 2D on successful shutdown.

Use the sleep feature

Use one of the available sleep configurations such as the Pin Sleep feature (SM=1) or sleeping through MicroPython (xbee.sleep_now()). When the module has gone to sleep and the SLEEP pin (pin 13) is low, power may safely be removed.

1. Initiate sleep (Assert SLEEP_RQ).
2. Wait for sleep state to be entered (SLEEP pin low).
3. Power off.

Airplane mode

Changing the XBee configuration to use Airplane Mode (AM=1) will also put the XBee into a safe state for shutdown. 

1. Set AM=1.
2. Apply configuration changes.
3. Wait 30 seconds to allow time for shutdown to occur.
4. Power off.