Dear,
When the NTP001 has lost synchronisation from GPS signal, I am wondering if I can get this information from the NTP packet.
Indeed, the LI (Leap indicator) in the NTP packet goes from 0b11 to 0b00 after powering up & after the first GPS synchronisation. However, if the GPS synchronisation is lost, the LI (Leap Indicator) does not return to 0b11.
Is there anyway to get this information (lost GPS signal) from the NTP packet ?
Best Regards,
Adrien Cléris
Hello Adrien,
Thank you for reaching out with your inquiry.
I’ve contacted our R&D team to review this scenario and confirm whether the current implementation supports indicating GPS sync loss via the NTP packet or if an alternative approach is recommended. I’ll get back to you as soon as I have an update from them.
Thank you for your patience in the meantime.
Best regards,
Hello,
Thank you for your patience.
To clarify, when a GPS fix is lost, the NTP server does not immediately update the Leap Indicator (LI) value to 0b11 (3). Instead, there’s typically a delay, often around 300 seconds, before this change is reflected in the NTP packet, depending on the configured polling interval.
In the same way, once the GPS fix is regained, the LI value does not instantly revert to 0b00 (0) – it’s subject to the same timing and polling behavior.
If you have any further questions or need clarification, feel free to ask here.
Best regards,
Hello,
Thank you very much for this information.
Best regards,