[gpsd-users] [gpsd newbie] Wrong time using Ublox

[Bertoni, Michele]

Hi to all!

I'm a newbie using gpsd: I need to create ntp server due I have no access to internet and I need my devices to be synced.

I'm using Raspberry pi so is not so easy get updated guide step-by-step to creating ntp server....

gpsd: 3.22 (revision 3.22)

Debian: bullseye

GPS: U-blox NEO 6-M

I get NMEA string, I get PPS, I also get wrong time: on my devices (Raspberry pi) I set at boot date of 1 Jan 2000, then I start manual-periodic syncing using ntpdate, then I check date.

Sometimes I get synced date at 1970 (or 1980, I don't remember), actually I use other ntp clients (such MikroTik routers) to check date.

I'm using https://www.timeanddate.com/worldclock/timezone/utc as comparison.

website: date year 2022, vs. MikroTik date year 1970 (sometimes) even if date at boot is set to 2000
website: date year 2022, time 15:20:40 UTC vs. MikroTik date year 2022, time 15:20:44 UTC (often)

at next sync:

website: date year 2022, time 15:30:42 UTC vs. MikroTik date year 2022, time 15:30:43 UTC

So when I get time I have no idea if time is correct.

I remember on Ublox datasheet there are some flags in NAV_TIMEGPS, time is not valid until flags get 0x07 value, so time I read is wrong by some seconds (maybe leap seconds?)....

It looks like gpsd gets wrong time from GPS.....

Any idea?

Thanks, Michele.