sync using GPS - nRF9160

[Lorenzo Amicucci]

Hi

in communication networks, GPS is often us to sync network elements and to get accurate timing.

with nRF9160 MFW 1.3, "GPS time based configurable IO-pin / pulse" is available; with 1pps pulse. 

To this regard:

• where is best documentation to read more about this functionality (how to set it up)
• for which use case this has been introduced?
• how can I use it in my application to sync all devices? 
  • example: if I want to make sure that all my devices have the same time and they are in sync, how can I use it?
    To have the same time on all devices, I guess they need to receive the Time of the Day at first (or from time to time) and then keep the sync using the 1pps pulse? or how?

Thanks

[Albrecht Markus Schellenberger]

Hello Lorenzo,

I again have to check with the modem team here. Answer can be delayed again, due to most of the experts are on summer vacation currently.

Regards,

Markus

[Kaja]

Hi,

Marcus is out of office, but here are some info back from the R&D team:

Lorenzo Amicucci said:

Using cellular, there is the %XTIME command to get unsolicited tiemstamp, but this to me is not necessary very accurate and some networks may not send this information, correct?

 - This is our understanding also.

Lorenzo Amicucci said:

--> if I set the pulse to happen at a precise time, (let's say at 12pm UTC every day; if possible?), which reference timing will be used to trigger this action? will it be at 12pm based on GPS? 

 - This is exactly what can be done with the 1PPS feature, and it will use the GPS time (converted to UTC) to trigger the action. There are several options to trade-off between accuracy and power consumption (all of them will be accurate from millisecond level down to tens of nanoseconds).

Best regards,
Kaja

[Lorenzo Amicucci]

Thanks. Second point is what I was looking at. 
I will close the ticket