Issue with STM32WB55 Zigbee Reconnection After Power Loss in Stop Mode

[Asem_Hassan]

Hello,

I am working with the STM32WB5M module and encountering an issue with Zigbee connections between the coordinator (coord) and an end device. The end device successfully reconnects and resumes communication upon waking up from the stop mode. However, if there is a power loss while the end device is in stop mode, it fails to reconnect after the power is restored.

I have implemented a filter in the coordinator's code to detect disconnections, but it seems that this filter only detects disconnections when the end device is not in stop mode. When the end device is in stop mode, the filter fails to detect any disconnections.

Could you provide guidance on how to ensure the end device can reliably reconnect to the coordinator after a power loss during stop mode? Any suggestions on modifying the filter or any other settings would be greatly appreciated.

[Ouadi · Accepted solution]

Hi @Asem_Hassan,

To make the connection automatically restored after the power off you have to implement the persistence data management as described in this AN document Zigbee Persistent Data Managament 

The coordinator can detect a disconnection of its child following many reasons :

• Polling mechanism :  the "poll" messages that are periodically sent to the parent to check for any pending data, if these messages are not sent due to a fixed timeout, it can infer that the child device may be disconnected
• Leave network : If the child performs a leave network, it will be removed completely from the network by the coordinator
• End device timeout Request : SED sends an End Device Timeout Request to specify how long the coordinator should wait before considering the device as disconnected.

Best regards,

Ouadi