Sleep mode handling

[matthias-bs]

Starting from the example simple_sensor_bme280.ino, I would like to enter sleep mode (on ESP32) for some time after a successful uplink. I implemented the NetSaveSessionInfo()/NetSaveSessionState() and their counterparts by writing the data to the ESP32 RTC RAM.

Now I am not sure about the proper sequence before entering sleep mode.

1. Do I have so call NetSaveSessionInfo()/NetSaveSessionState() or has the state already been saved before entering doUplink()?
2. I think I have to call Arduino_LoRaWAN::Shutdown() - what does this actually do? Disconnect gracefully from the network? Set the radio transceiver into power-down mode?

Any help is appreciated!

Thanks and best regards
Matthias