Zigbee motion sensor - Child left the network issue

Hello, 

Very new to Zigbee. Trying to use nrf 5340 dk as a Zigbee Coordinator to connect to a Thirdreality and a Sonoff PIR motion sensor. No modification (expect adding J-link logger project configs) was done to the Zigbee Coordinator sample code. I am on connect SDK 2.6. Here is the terminal output when trying to connect to the Thirdreality sensor. Same issue happens on the sonoff sensor as well: 

As you can see. The device is leaving the network after timeout. I am not sure what the issue is. I went through previous Devzone issues where people faced similar problems and fixed it but no-one really explained exactly how. However most pointed out that link key might be mismatching. But i am guessing that is set to ZigbeeAlliance09 by default.  Also, there is no install key on these sensors.

Here is the wireshark output sniffed with a nrf52 dongle. Inspecting frame 149 and 226, the nrf53 dk sends a leave command to the device. No idea why: 

4212.zigbee_sniffer_i.pcapng


Thanks for taking a look into this. 

Best regards, 
Sid

  • Quick update: Following another devzone post, I turned on ZIGBEE_PERMIT_LEGACY_DEVICES, and now it is working, the devices connected fine and been sending motion data. So I guess key exchange is an issue? Not sure what the issue could be yet though.

  • Hi Sid,

    Thank you for the update and good job on finding a solution! The sniffer logs shows that the end devices are using legacy commissioning.

    You can also enable legacy support on the Zigbee Coordinator with zb_bdb_set_legacy_device_support(1).

    Best regards,

    Maria

  • Hi Maria,

    I would like to understand how can we understand from sniffer logs if the end device is using legacy commissioning?

    Regards,

    Anusha

  • Hey Anusha,

    I will look for a Request Key from the ZED. If I don't see one, the device is likely a legacy device.

    Best regards,

    Maria