Zigbee Sleepy End Device (SED) CPU wakes up frequently, approximately once every second

RE: Zigbee Sleepy End Device (SED) CPU wakes up frequently, approximately once every second

Maria Gilje — Thu, 03 Sep 2026 06:24:46 GMT

Hello,

Thank you so much for your patience. I can confirm that I can see the same periodic spikes on the Light Switch sample on an nRF52840 DK. These spikes are most likely related to the ZBOSS stack sending ZB_COMMON_SIGNAL_CAN_SLEEP periodically.

This behaviour is intended and the documentation for the signal can be found here: https://ncsdoc.z6.web.core.windows.net/zboss-r23/4.2.0.0/group__zb__comm__signals.html#gae4c50bae666f2c4dd8ac710481856a6e

Best regards,

Maria

RE: Zigbee Sleepy End Device (SED) CPU wakes up frequently, approximately once every second

sangphan — Fri, 14 Aug 2026 10:55:45 GMT

Are you observing this periodic wake up on your custom board? --> yes

Have you ran one of our SED samples on your custom board or on an nRF52840 DK? Do you see the same wake up pattern in those cases? --> yes, I built the Light Switch sample and ran it on my custom board. I observed the same behavior: the CPU still wakes up approximately once every second. It only wakes up briefly; the radio is not turned on

RE: Zigbee Sleepy End Device (SED) CPU wakes up frequently, approximately once every second

Maria Gilje — Thu, 13 Aug 2026 15:07:23 GMT

Hello,

I have a few questions for you before I start looking into this properly.

Are you observing this periodic wake up on your custom board?

Have you ran one of our SED samples on your custom board or on an nRF52840 DK? Do you see the same wake up pattern in those cases?

There is quite a few nRF Connect SDK versions from v2.5.1 and v3.4.0 (which the Zigbee R23 add-on is based on), but we do have migration guides available for your reference: https://nrfconnectdocs.nordicsemi.com/ncs/3.4.0/nrf/releases_and_maturity/migration_guides.html

Best regards,

Maria