RAK811 time synchronization

LPWAN Modules / EVBs RAK811
1

Hi,
Is there any way to syncronize the time from the server using the DeviceTimeReq mac-command and give it throug serial?

Thanks

2

Hi @rayman18
For now RAK811 only support LoRaWAN 1.0.2 Specification. DeviceTimeReq/Ans is part of LoRaWAN 1.0.3 Specification.
Maybe it will be updated in future. @Fomi will be more competent here.

Regards
Todor

3

Thanks @velev
Let´s wait for @Fomi answer.

4

Hi @rayman18,

Yes, RAK811 now only support LoRaWAN 1.0.2 specification, and in future, we’ll support 1.0.3 surely, but maybe we can start to do it several months later.
So, RAK811’s firmware can not support DeviceTimeReq recently.

1 Like
5

hi @Fomi
any update to get network time ?

6

Hi @leanofis,

Sorry for that, it hasn’t supported Time synchronization yet.

7

hi @Fomi

It’s a 3.3V dc-dc buck converter as the power supply of my RAK4200.
Converter output ripple is 20mV, 200Khz at 100ma.
For that there are 4.7uF and 100nF SR7 capacitors placed near VDD.

Need more noise reduction ?

8

Hi @Fomi,

Any news here with the 1.0.3 support (I’m using RAK5205)?
If not - what other way do you recommend to download the server/gateway time to the device?
Thanks

9

Hi @sagis,

There is no news about the 1.0.3 support yet. Sorry.
About the time synchronization, we have a product based on RAK811 module too customized for a customer, and it can do the time synchronization succesfully. What we do in this product is only send a time synchronization message to the server for time synchronizing when the device power on or when it works for 1 day.

Maybe you can do it like this method.

10

Hi @Fomi ,

In my application the gateway (RAK 7243) and the nodes (5205) should sleep most of the time. They wake up every 30 min and should do some work and communicate.
Is it better to implemented this with class B? The RAK7243 and RAK5205 support class B (device receive data on ping slot and not only after uplink)?
Thanks

11

Hi @sagis,

In my project, the LoRa node device need work in sleep mode most of the time too. But even if it work in sleep mode, the RTC still work. So i think it is possible for you to use my method in your usecase.
Class B is a good choice too, but unfortunately, RAK7243 and RAK5205 haven’t supported Class B yet.

12

Hi @Fomi,
I have some node devices and all might have different RTC drift so the gateway should sync with all of the nodes.
What would you suggest?
Thanks

13

Hi @sagis,

Sorry, i think it is same for one node or some nodes. Every node can do the time sync frequently or when it wakes up.