Sensor node as OpenThread sleepy end device.
Experimental sketch using an Adafruit ItsyBitsy nRF52840 Express board and an alternative Arduino package by soburi with OpenThread support. To get a complete picture, have a look at Brezensalzer/ot-nRF52-experiments.
The ItsyBitsy was modified to achieve the lowest possible quiescence current:
- the Dotstar LED was removed
- the LDO regulator was removed
The Arduino libraries are not able to deactivate the nordic softmodem once enabled, leading to a quiescence current of 275 µA. Therefore the sketch starts with the delay() (equivalent to sleep), starts the measurement, connects to openthread and sends the message. Afterwards a soft reset is performed.
This results in a quiescence current of 2.7 µA.