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!

[awneil]

Do you really need at RTOS at all?

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

[Fyodor Prokopovich]

Yes, but the question wasn't that

[awneil]

But you could save yourself the question completely ...

[Nguyen Hoan Hoang]

For the nRF5x, FreeRTOS is supported in the SDK.

[wpaul]

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).