How to obtain the current date and time on BG95-M6 without using an NTP server

IoT Modules LPWA Module
1

Hello,

I am using a BG95-M6 module and would like to obtain the current date and time without using an NTP server.

I understand that the module can automatically receive the time from the cellular network when it connects. However, I would like to retrieve the current date and time manually by executing an AT command when needed.

My questions are:
1. If I execute the AT+CTZU command, will the module retrieve the date and time from the network?
2. Is there any recommended AT command to obtain the current date and time from the network?

Thank you for your support.

2

pls run and try

AT+CCLK?

3

Thank you for your reply.

I understood that the value returned by AT+CCLK? is updated when the module connects to the cellular network.
If I execute AT+CCLK?, will the module retrieve the current date and time from the network at that moment and update the RTC?
Or does AT+CCLK? only return the time that was previously set when the network connection was established?

4

No, during the UE’s registration process in the network, the EPC transmits the NITZ time via NAS signaling to the modem. The modem then acquires and synchronizes this time with the system and clock management unit. Subsequently, the internal RTC takes over the timing. The UE only obtains this time once upon startup.

5

Thank you for your reply.

I understand that the RTC is synchronized with the network time (NITZ) only once during the UE registration process at startup.
However, I would like to periodically correct the RTC in the BG95 because the internal RTC may drift over time.

Would the following methods be appropriate for updating the time?

  • Disconnect and reconnect the cellular network to obtain the network time (NITZ) again.
  • Use the AT+QNTP command to synchronize the time with an NTP server.

Are there any other recommended methods to periodically update or correct the RTC?

6

Yes, both of the two methods you described are correct.

7

Thank you for your response.

Just to confirm, is my understanding correct that executing AT+QLTS=1 or AT+QLTS=2 does not adjust or update the date and time of the BG95 via the network?