connectless CTE TX/RX problem

[loquat]

I am testing connectless CTE RX/TX.
A strange behavior is occurring.
Please advice me.

・connectless CTE TX
     nRF52833-DK + nRF Connect SDK + connectless CTE TX (almost same as sample)
・connectless CTE RX
   nRF52833-DK + nRF Connect SDK + My Application (customised connectless CTE RX)
   Scan doesn't stop after sync_create().

1. CTE is received normally for several tens of minutes.
2. Suddenly reception on the connectless CTE RX side stops. (stop scan)
3. If you start advertising while reception is stopped, you will be able to receive it.
4. When advertising stops, reception also stops. (stop scan)
5. If the connectless CTE TX is operating (transmitting) while advertising is running, reception will not stop even if advertising stops.

Is there anything we can investigate?

[Simonr]

Hi

Just wanted to give you an update. This pull does seem to mitigate the issue, as it happens less often, but it's still there. Sometimes it takes 10+ hours to recreate though. 

We've found out that the reason this happens is that the RTC0 seems to stop for some reason after some time has passed, and we're currently looking into why this is.

I will be out of office for the coming weeks, but my colleague Hieu will take over DevZone communication, and let you know when the development team has any updates on this issue. Thank you for your patience!

Our development team also requested that you make a github issue for this, as it is a bug in the BT controller we would like to address in a future release, and adding it to the GitHub issues would be best for them to address this.

Best regards,

Simon

[Hieu]

Hi loquat,

My apology for the long silence. I would like to confirm a fix before updating you.

Currently, we have a promising fix here: https://github.com/zephyrproject-rtos/zephyr/pull/63560.

During the tests that I have run the past week, I see that further power cycling the TX board a few times every now and then can cause the issue to happen much faster.
With the fix linked above, however, my current test setup has run more than 24 hours, with me frequently try power cycling the TX board.

If you wish, please consider giving it a try. You can cherry-pick that fix to your zephyr repository. If you do, please run cherry-pick with merge strategy to prefer "theirs" code.

I will be out of office next week, but Simon will resume supporting you for this case.

Best regards,

Hieu