Time Synchronization

The Yocto-BSP images for the ModuCop Edge Computer MEC01/02 support time synchronization via NTP (Network Time Protocol) and GPS (Global Positioning System).

It uses chrony for time synchronization, which is a versatile and powerful NTP client and server.

Statical NTP Servers

You can configure the default NTP servers in the file /etc/chrony.conf. By default, it is configured to use Google NTP servers, but you can change it to use your own NTP servers if needed.

DHCP NTP Servers

In addition, since image version 2.10, chrony takes also NTP server that are provided via DHCP (Option 42) into account. So if you have a DHCP server that provides NTP servers, the ModuCop will automatically use them for time synchronization (in addition to the statically configured NTP servers).

If multiple network interfaces are active and provide NTP servers via DHCP, all of them will be used for time synchronization.

GPS Time Source

If you have the GPS antenna connected to the ModuCop - and the GPS receiver is providing a valid time signal, you can also use it as a time source for chrony. chrony will automatically use the GPS time as a reference clock if it is available and valid.

You can verify the time synchronization status and the sources used by chrony with the command chronyc sources -v or chronyc tracking.

RTC Synchronization

chrony will also automatically synchronize the real time clock (RTC) of the ModuCop with the GPS time, so that the time is preserved even when the device is powered off.