Main loop in Asset Tracker application

RE: Main loop in Asset Tracker application

andrew926 — Fri, 15 Jan 2021 21:18:00 GMT

Thank you!

RE: Main loop in Asset Tracker application

Carl Richard — Fri, 15 Jan 2021 14:09:34 GMT

Got some information from the developers aswell!

In the default case where the asset tracker uses nRF Cloud, the thread handling the cloud connection is found here: https://github.com/nrfconnect/sdk-nrf/blob/6c63feff14df3da9d7171f9122d8cc66cd882bc9/subsys/net/lib/nrf_cloud/src/nrf_cloud.c#L494

The cloud event handler in asset tracker's main.c is called from this thread context

https://github.com/nrfconnect/sdk-nrf/blob/6c63feff14df3da9d7171f9122d8cc66cd882bc9/applications/asset_tracker/src/main.c#L1391

Best regards,
Carl Richard

RE: Main loop in Asset Tracker application

Carl Richard — Fri, 15 Jan 2021 13:23:40 GMT

Hi, Andrew!

There is no particular need for main in NCS. In fact, some Zephyr samples doesn't have a main at all! There will still be various threads running, e.g. in the drivers and workqueues. While I don't remember all the details on how the asset_tracker does things, when the cloud responds to the connection request, a event handler will be called, which starts the next step, which triggers new events, etc.

If you want to untangle it I suggest that you look for places where threads are started (sometimes before main) and items are put in workqueues.

Best regards,
Carl Richard