Zigbee: Deep sleep without rejoin using RTC FAST Memory (TZ-1384)

[michapr]

Is your feature request related to a problem?

Using the energy efficient deep sleep mode the device must rejoin to the Zigbee network after wakeup because all session information is lost. This take additional time (energy).

Describe the solution you'd like.

I would like to save all needed information (data) to the RTC FAST Memory, it will not be lost in deep sleep mode (if right configuration). So after start we could check the RTC RAM value - if valid, the join procedure can be skipped.

If connection is multiple times not possible the rejoin can be forced (set RTC values to invalid)

Describe alternatives you've considered.

No response

Additional context.

a similar method was implemented for the ESP32 at LoraWan

[chshu]

a similar method was implemented for the ESP32 at LoraWan

Could you share some more infomation on this feature?

The needed information include the runtime information all over the stack, it's challenge to put them together.

[michapr]

Hi,
here you can see the example code for ESP32 LoRaWAN -libraries and discussions in Github available
https://github.com/radiolib-org/radiolib-persistence/blob/main/examples/LoRaWAN_ESP32/LoRaWAN_ESP32.ino

This are really too much information for store/restore using RTC memory? I don't think so... But it could save very much energy for sleeping devices (like sensors) if ESP will be live only for such a very short time for reporting.

Thank you!

[chshu]

@michapr Does the device need to go through the rejoin process in this step: LoRaWAN_ESP32.ino#L102?

You may refer to a previous discussion here: #9 (comment).

[michapr]

Does the device need to go through the rejoin process in this step: LoRaWAN_ESP32.ino#L102?

As far as I remember/know - yes. But this is not a real rejoin, it is only for restoring the internal "session parameters" (simple said...)
The online time is very small, only for LoRaWAN transmission. Have tested it and it was working fine with HELTEC devices and ESP32/RFM module. Have created some solar powered sensors based on this.

Would be really nice to support the deep sleep mode for H2/C6 modules.