zb_zdo_mgmt_lqi_req occasionally does not call the callback

[MartinPersson]

We've noted that our coordinator sometimes hangs and it's because that sometimes, maybe once every 1000-10000th call, the zb_zdo_mgmt_lqi_req API never responds to the callback and our code gets stuck on a semaphore waiting on that reply. I've checked that we get a buffer from zb_buf_get_any and that zb_zdo_mgmt_lqi_req does not return 0xff, so everything looks right.

Is there a better, more preferred, way to get the list of connected end devices or is this it and I should rework the code to be prepared that it might not always get a response?

I guess this could be considered a bug in the Zboss library? We're running version 3.11.1.5.

Regards

/Martin 

[Marte Myrvold]

Hi Martin,

Which SDK and version are you using?

Is there a better, more preferred, way to get the list of connected end devices or is this it and I should rework the code to be prepared that it might not always get a response?

Do you want to get the neighbor table of the coordinator itself or the other devices in the network? If you are only interested in the former, you can use zb_nwk_nbr_iterator_next() instead of sending a Mgmt_Lqi_req.

Best regards,
Marte

[MartinPersson]

Hey. Sorry for late answer.

ZBoss is 3.11.1.5, SD is 7.0.1, MDK is 8.51.0. Do you need some other version?

Yes, I only need the local neighbours, we're not using any routers.
Where can I see example code for zb_nwk_nbr_iterator_next? Didn't find any when googling and the documentation doesn't explain very well how to call it.

[Marte Myrvold]

Hi,

MartinPersson said:

ZBoss is 3.11.1.5, SD is 7.0.1, MDK is 8.51.0. Do you need some other version?

Are you using the nRF5 SDK?

MartinPersson said:

Where can I see example code for zb_nwk_nbr_iterator_next

This function is used by the Zigbee shell libraries in the nRF Connect SDK, so you can find an example here: https://github.com/nrfconnect/sdk-nrf/blob/v2.7.0/subsys/zigbee/lib/zigbee_shell/src/zigbee_shell_cmd_nbr.c#L137.

Another option to get the neighbor table is to manually go through the contents of gc_neighbor. You can see an example implementation of this in the nRF5 SDK here: https://github.com/martelmy/Zigbee-examples-nRF5-SDK/blob/main/helper_functions/zb_helper_functions.c#L25-L79. Please note that this code is not official and is considered provided as-is.

Best regards,
Marte

[MartinPersson]

Hi, sorry for late reply again. Lots to do before release.

I think I've found the problem. As the danes say: Error 30; the problem is approximately 30 cm in front of the screen.

If I do check that I actually get a buffer allocated before trying to call the function I bet things will work better. I thought I checked, but apparently not.

Sorry about that.

I'll get back to you if there's still a problem remaining when I do check for a buffer.

Regards

/M

[Marte Myrvold]

Hi,

That sounds like a likely culprit and something that can be easy to miss  

Let me know if you still have any issues after adding the check!

Best regards,
Marte