RTOS selection

[Fyodor Prokopovich]

Hey.
I'm looking for a complete free   RTOS for the commercial development of our startup.                                                                                                                                                                                       We will use the SEGGER Embedded Studio IDE and SoC Nordic nRF52840.                                                                                                                                                                                                        As I understand, SEGGER Embedded Studio is free for users any ARM Cortex-M based device in the nRF series.                                                                                                                                       Is SEGGER embOS free for Nordic users? or does co-operation SEGGER and Nordic don't apply to it? and I only have freertos?
Thanks!

[himanshu pande]

Hello Fyodor,

FreeRTOS is ported for nrf52. The porting does take care of soft-device timing dependencies. As far as I understand, embOS is not free for commercial development.

That being said, the nature of soft-device implementation(or BLE timing constraints, I should say) doesnt allow you to have "critical sections" in the code violating the prime spirit of an RTOS.

If you are looking only for portability, freeRTOS is a good choice. If you have real time timing constraints, either use Timeslot API or use radio notifications to generate that required critical section.

Best Regards,

Himanshu.

[PC]

Hello himanshu and wpaul

Do you know of any nRF52 examples of RTOS + SoftDevice BLE + low power sleep?

Looking for all 3 to run together..

The SDK example "Heart Rate Free RTOS" has RTOS + SD but not going to sleep.

The SDK example "Blink RTC FreeRTOS" has RTOS + sleeping but no SD.

Thanks!

[awneil]

So can you not pull your required parts from those examples?

At some point, you have to start doing some original work ...

[PC]

Does this mean there is no example that you know of?

We've ran into difficulties, have not been able to get it to work, but are still working on it..  Right, we have not been able yet to pull the required parts from those examples.  Therefore in the meantime asking if there is any generic example to at least prove the concept all together, and help give us some idea of one way to make it work.  I'm not using FreeRTOS but would like to see an example with any RTOS at this point.  It's unexpected to see the SDK 15.2 and 15.3 example non-RTOS "Heart Rate" indeed running low power sleep but the equivalent "Heart Rate FreeRTOS" not sleeping.. 

[kirkus]

In order to get the SDK 15.3 Heart Rate FreeRTOS example to sleep, I had to implement the FPU_IRQHandler as mentioned here, even though I wasn't experiencing any divide by 0 issues.