9160 ntp data_time

[William.wei]

hi support team.

i want to use time from ntp server, and we have example in nrf/lib/data_time;

after devzone searching, i added below setting to prj.config

CONFIG_DATE_TIME=y
CONFIG_DATE_TIME_MODEM=n
CONFIG_DATE_TIME_NTP=y

CONFIG_BSD_LIBRARY=y
CONFIG_DATE_TIME_UPDATE_INTERVAL_SECONDS=20

and added code after k_sem_take(&lte_connected, K_FOREVER); in NCS1.5.0 udp example. i was using cat-NB

int64_t unix_time_ms;

err = date_time_now(&unix_time_ms);

/*Print the current time */
printk("Date_time: %d %d\n", (int32_t)(unix_time_ms/1000000), (int32_t)(unix_time_ms%1000000));

compile is ok, flash is ok, but there is one problem that can't get ntp server addr as below:

00> *** Booting Zephyr OS build v2.4.99-ncs1 ***
00> UDP sample has started
00> W: getaddrinfo, error: -11
00> W: getaddrinfo, error: -11
00> W: getaddrinfo, error: -11
00> W: getaddrinfo, error: -11
00> W: getaddrinfo, error: -11
00> W: Not getting time from any NTP server

however in windows, i can see the the server is ok, as below, for now i don't know how to fix this. could you please help to confirm where is the problem

Regards,

William.

[William.wei]

i guess that 9160 didn't attach to network, but the ntp function is working after i config the ntp parameter, so getaddrinfo returns fail, so i guess how to delay the ntp function is the key point.

[Heidi]

Hi! 

 

This is a very common error to see if your local carrier does not provide DNS servers. You could try setting it manually, as shown here, and see if that works?

https://devzone.nordicsemi.com/f/nordic-q-a/50029/nrf9160-modem-firmware-v1-0-0-setting-custom-dns-server/235419#235419

Best regards,

Heidi

[William.wei]

from developer document, we can see that  data-time library requests time from the onboard modem of nRF9160, may i ask where the time comes from? the base station?

[Heidi]

When the library gets the time from the modem, it sends the AT command "AT+CCLK?" and uses the return as the time. 

 

According to the +CCLK documentation, the device clock updates are based on network time when available. The time can be requested using the read command, but not all networks provide the information, nor can the highest accuracy requirements be guaranteed, either.

So the time comes from the network.