RTOS selection

RE: RTOS selection

kirkus — Sat, 04 May 2019 13:03:39 GMT

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.

RE: RTOS selection

PC — Thu, 14 Mar 2019 21:23:28 GMT

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..

RE: RTOS selection

awneil — Thu, 14 Mar 2019 18:38:36 GMT

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

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

RE: RTOS selection

PC — Thu, 14 Mar 2019 18:27:57 GMT

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!

RE: RTOS selection

himanshu pande — Mon, 28 Jan 2019 13:02:32 GMT

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.

RE: RTOS selection

haakonsh — Mon, 07 Jan 2019 13:31:52 GMT

I have to agree with @awneil, you should not use an RTOS with the nRF5 SDKs unless absolutely necessary.

That being said the new nRF Connect SDK uses the Zephyr RTOS.

RE: RTOS selection

wpaul — Fri, 04 Jan 2019 20:29:38 GMT

ChibiOS (http://www.chibios.org) also runs on the nRF52 devices. (Go here: https://github.com/ChibiOS and look at the ChibiOS-Contrib repo.) It is open source, however if you're producing a commercial product, you will likely need to pay for a license for it.

Note that currently it only has support for the nRF52832. I have it running on the nRF52840 for a personal hobby project. It's not difficult to port. However I've had to write some of my own drivers (notably for SPIM, QSPI and I2S). I've also done some work to use it in conjunction with SoftDevice S140. Everything works, but since I'm not using the Nordic SDK, there are a lot of things I have to implement myself. Also, for building I just use a GCC cross-compile toolchain, along with OpenOCD and GDB for flashing and debugging. (OpenOCD now supports the nRF52840 out of the box.) My host environment is FreeBSD, but Linux, MacOS or Windows should also work. To build, go to the badge_840 directory and run "make." (You need to have arm-none-eabi-gcc in your path.)

The project isn't done yet, but if you want to look at it, it's here: https://github.com/netik/dc27_badge/tree/master/software/firmware

As I said, this is a hobby project only. I'm not providing any support for it. If you want to have a look at it, fine, but if it breaks you get to keep both pieces. :) It wants to use a display controller and external I2S codec which don't come with the nRF52840 DK board. However you should be able to build it and boot it up even without those components (you'll get a shell on the serial port).

RE: RTOS selection

Nguyen Hoan Hoang — Fri, 04 Jan 2019 18:49:55 GMT

For the nRF5x, FreeRTOS is supported in the SDK.

RE: RTOS selection

awneil — Fri, 04 Jan 2019 16:34:50 GMT

But you could save yourself the question completely ...

RE: RTOS selection

Fyodor Prokopovich — Fri, 04 Jan 2019 16:21:16 GMT

Yes, but the question wasn't that

RE: RTOS selection

awneil — Fri, 04 Jan 2019 16:17:41 GMT

Do you really need at RTOS at all?

Many (most?) nRF5x projects have no RTOS at all ...