Using Flash as Non Volatile Storage on Raspberry PI Pico with FreeRTOS & SMP | drjonea.co.uk

I looked at using Flash memory on the Raspberry PI Pico and Pico W to hold non-volatile variables back in the video: • Unlocking The Power Of... . That looked at running on Pico in a Bare-metal mode, i.e. just using the Pico SDK.
In this video, I look at how to provide the critical section controls to make this safe to do under FreeRTOS and FreeRTOS SMP. With many tasks running at the same time.
Doing this on FreeRTOS in a single core mode is straightforward. Doing it under FreeRTOS SMP with dual cores reading instructions from the Flash is not so easy.
The code can all be found in the repo: github.com/jondurrant/RPIPico...

[@Yakroo108]

👍👍👍

[@DrJonEA]

Thank you. Always great to get feedback and encouragement.

[@drfrancintosh]

i am curious - does RTOS have a concept of "resources?" because both the cores and the Flash are resources that can be allocated and considered critical. im curious as to if i will need to extend rtos for every Pico resource i need to protect.

[@DrJonEA]

Yes absolutely does. The issue here is that flash is so fundamental to the operation of both cores.

[@drfrancintosh]

@@DrJonEA thanks! i'm signing up for your udemy course. i'm way behind on Cmakelists.txt. i'm building my own library for Pico and am at a loss since (back in the day) one delivered a lib.a file and a folder of .h files. The idea of delivering all the source code and recompiling it every time is a bit foreign to me.
Thanks for your work. I'm subscribed. Continued Success!

[@DrJonEA]

Thank you for signing up. CMake is building "lib.a" in the background, but managing when to update them.