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INDI Library v2.0.6 is Released (02 Feb 2024)

Bi-monthly release with minor bug fixes and improvements

Anomalies in KStars/Ekos/Indi time using GPS

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I have been experiencing a very unusual glitch that manifested as an apparent drift in the telescope location on the sky map over time, while the physical mount tracked properly. After careful observation I noticed that each time the GPSD driver refreshed itself, rather than fetching the correct time it instead applied the time of the very first fix obtained, effectively turning back the clock each time.

As a work around I can switch the GPSD time source from GPS to System, which is properly set with NTP.
For clarity, the system run GPSD service is getting the correct time, confirmed via gpsmon and cgps
4 years 3 months ago #46488

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If this is not repeatable and I'm the only one experiencing it, I would like to know, maybe the issue is in my configuration.
Although I believe I experienced this on my retired raspberry pi 3 as well. I'll probably have to check.
4 years 3 months ago #46525

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No your are not the only one, I get this now and again - but as it happened with Astroberry testing and "virual GPSD Device" I thought it was just a glitch as Astroberry is so new.

Just wonder is there so kind of Cache problem that is giving "old" data when new data is not available - failed fix or no fix or time out !.

I would admit that I would still expect the time to catch up when a new "fix" was correctly acquired which I think it does with my version of he problem.

Again using CGPS etc produces the correct time so the problem should not be the std Linux GPSD service but with the client maybe.

The only way I stop this effecting anything is to stop the refresh (Indi's refresh time made longer) after you have got a decent fix and intial time set up - I presume afer this you dont need time or location updae anyway - or is RPI time that bad once set ?

A hard error to find I guess!

I use Ublox7 .

So you are not going mad :-)
RPI3 Ubuntu 16.04 / AMD desktop Kstars under Ubuntu 16.04 Mounts :azeq6 ,SWAZGoTo

RPI3 Fedora testing out on AMD desktop Fedpra 28 - running kstars 2.9.4 , Indilib 1.7.4 ?????
4 years 3 months ago #46554

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Phew. I have a reliable signal with an external antenna attached, so getting the fix is no issue. And yes, setting the refresh to 0 is one way around it too. But I've also observed it will initially sync to the beginning of Unix time in 1970. And then, once refreshed with a fix to the current time it is susceptible to that reset.
4 years 3 months ago #46557

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My signature explains how I use KStars/Ekos/Indi. On a cloudy night last night, I (finally) sat down and looked in detail at the way my GPS data updates the RPi4 system time and KStars time and location. I am running GPSD with gpsd-clients and python-gps installed and I am also running chrony to update the system clock.
Within a minute or so of switching on, the system time updates to GPS time. I then open KStars and note that the LT display matches the system clock. I run Ekos with a simulator profile with GPSD. The next GPS fix updates time and location in KStars, but the KStars LT display is now approximately 6 seconds behind system time. Setting KStars time to Now (Ctl+E) updates the LT to system time again, but any updating by the GPS makes the LT appear to be 6 seconds slow again. It's not critical and I can work around this, but wonder if someone has noticed the same anomalies?
4 years 3 months ago #46900

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4 years 3 months ago #46935

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I have tried to move this to the older thread mentioned above, as requested, but for some reason I am having issues, I have asked Jasem to try.. :)
4 years 3 months ago #46945

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For some bizarre reason, Avocette's thread originally titled Anomalies-in-kstars-ekos-indi-time-using-gps, ID # 6132 was mashed together with this thread discussing guiding calibration.
And yesterday I noticed something was off when I replied once, then later the page had a 403 error, seemingly the thread was removed, but reposted, to which I repeated my reply referencing the GPSD glitch I had previously reported.
4 years 3 months ago #46952

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Yes there was an issue yesterday, which I reported to Jasem as I could not merge the post as was requested, I asked him to try and do it, and then Jasem moved to the wrong thread...I have told him, and he said he was going to fix...there have been issues with the forum and he has been working on it... :)
4 years 3 months ago #46959

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As it stands, this entire thread's title has been incorrectly relabeled and the GPS posts are still combined with it.
4 years 3 months ago #46978

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I have informed Jasem, that he has got it wrong....... :(
4 years 3 months ago #46991

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