nrf52840 - Zigbee attribute report timing issue

[javierbio]

Dear community, good afternoon

We have been working with a coordinator, a router device and an end device based on nRF52840 with nRF5_SDK_for_Thread_and_Zigbee_v4.0.0_dc7186b

All the devices are Zigbee 3.0 and implement Install Codes. The end device & router device cluster = 0x0201 (Thermostat) are binded

Under normal circumstances the end device reports different attributes every 60 seconds (except for Cluster=0x0201 AttrId=0x0012 which reports every 120 seconds) to the coordinator and router device (for the router device it only reports Cluster 0x0201 - Attributes 0x00, 0x08 and 0x21)

Then after a while this timing changes and the end device start sending reports with different intervals

Enclosed you will find a Wireshark capture (sorry for the lenght) .

The network addressess are as follows:

End Device Zigbee NWK Address = 0xab60

Router Device Zigbee NWK Address = 0x4bff

For ease of reading of the capture, for example you can use the following filter: zbee_nwk.src == 0xab60 && zbee_nwk.dst == 0x44bf && zbee_zcl.attr.data.type == 0x20

As you will see, the end device sends a report every 60 seconds until line 3010. The later reports are later sent every 90 seconds with several retransmition attempts.

1727.20201009 - Wireshark Capture.pcapng

Any thoughts on what could be causing this behaviour?

Thanks for your support.

Best regards,

Javier.

[Edvin]

Hello,

The retransmissions, such as packets 3694 and 3697, are relays. If you look at the packets, you can see that the first one (3694) has src: 0xab60, dst: 0x0000, and the second one (3697) has src: 0x0000 and dst:0x44bf:

However, on packet 3734 there is a retransmission in packet 3735, because it was not Acked by the coordinator. 

I see that in packet 3155, you have a rejoin request from the 0xab60 device. Do you know why this is there? Perhaps you encounter some application error? If so, perhaps the device randomly resets, and rejoins the network, and this may be why the device is a bit off with the time. 

[javierbio]

Dear Edvin, good afternoon

Thanks for you reply.

Ok I see the rejoin attempt. I will check this closely.

Best regards,