GPS stopped working

Bug Reports
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#545

I’d love to know what you’re doing “wrong”.

I can have my XA2 sitting outside in full view of a totally clear sky and have it take 15 minutes or much longer to get a lock, yet my Amazfit GTR 2 takes less than a couple of minutes.

My X without a sim card (therefore it cannot use MLS Manager) will get a lock within a minute or two, my Jolla C without a sim card gets a lock almost immediately.

The XA2 can get a lock reasonably quickly occasionally but it’s not reliable enough to be able to use it as a navigation/sports tracking device.

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#546

Do you maybe leave the positioning always/often enough on?
On the XA2, the hard part is to get a fix after some time without GPS use.
If the GPS is often fed with some up to date data, it seems to help.
Anyway, still a headache.

Once again, problem is not the XA2 itself but SFOS+XA2. As it gets a fix quickly in Android, even right after reflash, offline, no SIM and GPS assistance data deleted (with Gps Cockpit and Satstat).

#547

I agree, the problem is a combination of the XA2 and Sailfish.

While I use the GPS (attempt to use the GPS) in the XA2 regularly there is very often a 2-300 km difference between locations and this also causes issues too I think. The data is up to date but for a different location to where the GPS was last used. I don’t have this issue with my other devices.

#548

Just to add some more to the mix, there’s also the issue that different devices may have different firmware and drivers. This could explain why some XA2s seem to suffer while others don’t.

#549

So, how to identify those (which?) drivers and firmware?

#550

That’s a good question, but also falls a bit too far outside my area of expertise I’m afraid. For the XA2, running the following over SSH should capture checksums of the firmware blobs on your device:

devel-su -c find /firmware/ -exec sha256sum {} \; > /home/defaultuser/Downloads/checksums.txt

Comparing the resulting ~/Downloads/checksums.txt files will allow you to tell whether two devices are running the same or different firmware.

But, in terms of finding out version numbers, etc. I’m not certain I’m afraid. If I can find out more info I’ll post it here.

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#551

I totally agree that finding a position takes longer e.g.after a flight or another major change of location unattended by GPS. For car navigation I normally start from and leave at places GPS has known before. And I allow a few minutes for a fix. Sometimes when there is not much change e.g. on motorways signal gets lost for a few seconds.

#552

Maybe the most important thing is that I keep moving while waiting for a fix. It seems to me that running an actual navigation works better than staying put and using only GPS Info or so.

#553

Have you tried the suplpatch approach, described earlier in this thread? The gps now works very well for me on my XA2 H4113 with this solution: I get a fix in just a few seconds being outside. Being inside, it usually takes about 20 seconds to get a fix moving near a window. If you haven’t tried suplpatch, it is worth trying.

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#554

No, I haven’t as yet. I’m very much a novice when it comes to using Terminal/Command Line. I need to allow a but of time before I bother with attempting the suplpatch option. I am keen to try it but beforehand I am contemplating doing a fresh re-install of Sailfish. I’m hoping to cure a few other niggles like the camera not working every so often without re booting.

#555

I have to emphasize again: It is not only a problem of the XA2 with Sailfish.

Other devices with Sailfish as well are struggling with GPS. Some more, some less. I had times when I didn’t get a fix within 20 minutes with my Xperia X. On the Pro1 that happens unfortunately more often. The funny thing is, that this is as well very differently every time. So it seems that satellite constellation seem to have a big impact (and of course weather as well). On both devices, it is sometimes possible to get a cold fix in less than 2 minutes (even on bad weather).

#556

There are two separate items: GPS vs Assisted GPS and XA2 HW issue. AGPS is always faster than GPS because it gets almanac etc. data via fast data link (cellular) instead of getting the data from satellites. This is not an error, it works as specified. Yes, it is annoying to wait but yet it is not an error.

XA2 has issue where display panel appears to partially block GPS antenna. Thus, XA2 needs much longer time and better reception to get location when AGPS is not available. Suplpatcher gets up to date satellite information via fast data link. Thus, barely working GPS reception in XA2 needs to work less and thus it can get GPS location in seconds.

Also note that not every XA2 appears to have the HW issue. Jolla seems to have working devices only; I have a poor one. So I bought 10ii and can get GPS location quickly even indoors without suplpatcher.

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#557

You’re right. It is not really a bug. Anyway, waiting 20 minutes on Satfix is not only annoying, but degrades GPS to be not really usable. So I really hope to see an official AGPS solution again. Even if that would mean I have to use Google servers (suplpatch isn’t working on Pro1) - as long as AGPS can be switched off. Sometimes I just don’t have the time to wait. Taking a second smartphone with me, can’t be the solution. Turning on GPS all the time (via GPSInfo) is just partly a solution. This eats quite a lot of battery and I can’t place my Phone all the time under clear sky.

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#558

Well, no, it is a bug, but a bug in the hardware design.

#559

Does it work better flipped (display oriented to the ground?)?
Because the antenna is right behind the back cover (which is grounded IIRC)

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#560

You might want to check what teleshoes wrote earlier in this thread. GPS stopped working - #320 by teleshoes.

#561

I noticed something different lately. If I have used herewe go maps to the last stage of trip than I can close it and let it sit for some time even with gps completly turned off. Even turn off a device. Then opening gpsinfo and here we go (In this order) gives a fix indoors or under any conditions <5 seconds, But I belive is some offline data injected with here we go. Not sure how it’s happening

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#562

If nobody else has this bug, what are some libraries etc to refresh that might fix it?

#564

Huu? I missed a so vital feature? Ho do you do to reset the GPS via GpsInfo?

#565

Pull-down menu, Deactivate then Activate.

What this actually resets, I don’t know. In fact, the behaviour may have changed in the last couple of versions. It used to force a 12+ min time-to-first-fix ie redownload the almanac. But recently, I’m pretty sure I got a lock within a minute after De-/Re-activating.

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