How to create a Low Power RTOS system code em C++ for ARM Cortex-M MCUs, a nRF52840?

[Claudio Rosa]

Good night,

I am developing a Firmware for a nRF52840 created by RAKWireless RAK4631, with VSCode/Platformio/C++/FreeRTOS, and now I am changing the Architecture from a Super Loop to a Event Driven.  The events will be, for example, a accelerometer that it will create some Interruption when the acceleration reach a specific level.

Now the challenge is to reduce the power consumption with a Low Power Architecture, with resources as sleep/deep sleep and tickless, based on the "4.3.6 System Control Register" in the "Cortex-M4 Devices Generic User Guide".

Where could I find some example about the subject described above?

Cláudio Rosa

[Susheel Nuguru]

FreeRTOS in C (not C++)  is supported and tested on our older nRF5SDK as mentioned in these documentation. .

The older nRF5 SDK is not deprecated. It will continue to be maintained for the foreseeable future. However, it will not support new features beyond Bluetooth LE 5. For new designs and for the nRF91 Series and nRF53 Series devices, the use of the nRF Connect SDK is recommended.

However, specific parts of the nRF5 SDK have been deprecated. For instance, the nRF5 SDK for Thread and Zigbee, and the nRF5 SDK for HomeKit are deprecated and will not be upgraded. For new projects requiring these features, the nRF Connect SDK should be used.

[Claudio Rosa]

Thank you by your support.

I will not work with BLE, because I have LoRa in the RAKWireless solution.  My target is a low power development, then where I can find some examples how to control operation modes: sleep/deep sleep/wake?

Claudio

[Susheel Nuguru]

All FreeRTOS examples in our SDK goes to "System ON IDLE" state (WFE on ARM Cortex M4) when the RTOS schedules IDLE task to run.

You can ofcourse change the behavior by plugging in a callback hook using vApplicationIdleHook to make the system go to deep sleep instead of idle sleep. 

[Claudio Rosa]

Thank you very much by your support.

[Susheel Nuguru]

Claudio, Glad I could assist.