Proper way to handle long computations while preserving BLE timing?

RE: Proper way to handle long computations while preserving BLE timing?

Kenneth — Tue, 21 Nov 2023 15:30:18 GMT

Not sure if I am not of much help in that kind of implementation, but do checkout the interrupt priorities that you have available when using a softdevice (if you haven't already):
https://infocenter.nordicsemi.com/topic/sds_s132/SDS/s1xx/processor_avail_interrupt_latency/exception_mgmt_sd.html

Kenneth

RE: Proper way to handle long computations while preserving BLE timing?

PowerConsumer — Tue, 21 Nov 2023 09:09:23 GMT

Hi Kenneth, thank you for your answer. Yes this is correct, we are indeed already porting to the nRF Connect SDK but currently still use nRF5. As the application is already quite complicated however, I was hoping there to be a solution to continue improving on the old app while the new one is still unusable. Would you be willing to look at two code files that illustrate my idea to relatively quickly implement a proper schedule for this case for some feedback? We already have a state machine which I think we can use to solve the interrupt issue.

RE: Proper way to handle long computations while preserving BLE timing?

Kenneth — Tue, 21 Nov 2023 09:05:47 GMT

I get the impression you are working on the nRF5 SDK, if you swap to the nRF Connect SDK this could be a bit easier, since you can put non-timing critical timings tasks (that take for instance take long time) into a workque that is handle at a low priority. You can also set threads with different priorities. You can learn more about nRF Connect SDK: https://academy.nordicsemi.com/

Kenneth

RE: Proper way to handle long computations while preserving BLE timing?

PowerConsumer — Tue, 21 Nov 2023 08:53:14 GMT

Hey, thanks for your answer! Makes sense. I'll try to make it work with the existing state machine.

RE: Proper way to handle long computations while preserving BLE timing?

d2sc — Mon, 20 Nov 2023 19:21:06 GMT

I usually split up long running tasks into shorter (5-20ms) chunks and put them in the scheduler queue.

In general it sounds like you are running into an issue where your application is not managing the priorities of different tasks. I recommend looking into the interrupt levels you have set for different operations -> and further more make sure the soft device is safely able to interrupt your application flow without causing issues.