Moto X (GPS) Laps are not recording properly with the GPS

[crazyxzer0]

Hi Harry,

I have a Moto X 2013 with Verizon.

I've been having an issue with the internal GPS logging in properly for laptimes.



The lap list mentions GPS sensor as External @ 0.0Hz

The last 3 pics were screenshot away from the track but they were in the same settings.





Previously my phone was mounted by the driver side a pillar and Harry mentioned that it should be in the center of the windshield. This time around I went with the center of the windshield and it still resulted in the same issue. Is there something I am missing as far as setting it up?


Any help would be great. I believe an external GPS would solve but I like to see if that can be avoided.

Thanks

[Harry]

Please check your database first (Check Data in Lap List). In case this "straight" is a track recording, there is something very wrong. I have no experience with the Moto X GPS, but the GPS screen shown is fine. The question is if it looked like this when recording the lap in the first snapshot?

Harry

[crazyxzer0]

Please check your database first (Check Data in Lap List). In case this "straight" is a track recording, there is something very wrong. I have no experience with the Moto X GPS, but the GPS screen shown is fine. The question is if it looked like this when recording the lap in the first snapshot?

Harry

Hi Harry,

I checked the database and it said no problems found. I'm not sure what do you mean the lap looked like this as I left it on Timer screen during the sessions.

Another thing I noticed is that not all lap lists seem to have the GPS data in it.




My Moto X was position like this in the snapshot of the Go Pro Video.




Hopefully it's something that can be fixed

[Harry]

Hi again,

My question has been if the initial snapshots are from a test drive or from a real track. From your last post (Lap List) I see it is a real track... The missing recording data in the Lap List shown means the system recorded times (i.e. had GPS positions), but had problems to store the individual positions of the track. To understand what the problem is, I'd need a trace log from test lap (e.g. around the block using a custom track). In case you would be willing to generate something like this, here is what needs to be done:

1. Setup a short "track" around the block using the New Track assistant.
2. Install the system the same way you did it on track.
3. Follow the instructions in viewtopic.php?f=8&t=1933 and enable tracing of classes 'GPS Sensor' and 'Databases'. Please make sure all other trace classes are turned off.
4. Run 2 or 3 laps.
5. Verify the issues appeared again (i.e. no / missing GPS data in Lap List).
6. Stop logging and send the log to me.

In case you cannot reproduce the missing data, verify difference between the test drive and track use and repeat the process.

Thanks a lot,

Harry

[crazyxzer0]

Hi Harry,

Yes the POI for Thunderhill were downloaded from your server for the lap lists in the first snapshot. When I have time during this week, I will give it a shot and make your test case and shoot it to you.


Thanks for the help.

[crazyxzer0]

Hi Harry,

I sent you an email with the trace. I am not sure if it had all the information in there.

How big of a "track" does it need to be? I only went around the block and the GPS data seems to be the same.

[crazyxzer0]

Hi Harry,

I sent you another email with a logfile attached. I redid the data logging again.

[crazyxzer0]

Hi Harry,

Were you able to verify if the logs I sent you were correct? Thanks

[Harry]

Hi,

Sorry, it took me a little longer... I'm entering Winter season already and are fully focussed on the next new major release

I had a look into the log. The problem is that the NMEA stream delivered by the MotoX is delivering valid and invalid fixes alternating. I have added a short sample below showing what is delivered for one second (i.e. 1 fix for a 1 Hz device):

Code: Select all

$GPGSV,3,1,21,02,13,063,34,05,43,057,32,12,16,165,26,18,11,202,26*74
$GPGSV,3,2,21,21,34,261,34,25,47,195,33,26,06,111,22,29,69,350,36*70
$GPGSV,3,3,21,31,08,272,28,13,02,045,,15,04,147,*4E
$GLGSV,2,1,21,66,55,113,32,82,26,307,32,80,23,300,23,79,21,241,25*6A
$GLGSV,2,2,21,65,30,040,34,88,26,082,27,81,56,012,38,67,21,172,32*6B
$GPGSA,A,3,02,05,12,18,21,25,26,29,31,,,,0.9,0.6,0.7*3E
$GPVTG,325.6,T,325.6,M,1.5,N,2.7,K,A*22
$GPRMC,184107,A,3754.218640,N,12218.621121,W,1.5,325.6,051114,0.0,E,A*07
$GPGGA,184107,3754.218640,N,12218.621121,W,1,09,0.6,14.0,M,-26.0,M,,*4B
$GPGSV,3,1,22,02,13,063,29,05,43,057,28,12,16,165,33,15,04,147,24*7D
$GPGSV,3,2,22,18,11,202,28,21,34,261,33,25,47,195,29,26,06,111,23*7A
$GPGSV,3,3,22,29,69,350,37,31,08,272,26,13,02,045,*47
$GLGSV,3,1,22,66,55,113,31,82,26,307,33,80,23,300,25,79,21,241,23*6A
$GLGSV,3,2,22,65,30,039,30,88,26,082,27,81,56,012,36,67,21,172,30*6F
$GLGSV,3,3,22,73,01,344,*53
$GPGSA,A,1,,,,,,,,,,,,,,,*1E
$GPVTG,,T,,M,,N,,K,N*2C
$GPRMC,,V,,,,,,,,,,N*53
$GPGGA,,,,,,0,,,,,,,,*66

The problem are the invalid fixes in the end. Looking just into RMC, we get a valid fix "$GPRMC,184107,A,3754.218640,N,12218.621121,W,1.5,325.6,051114,0.0,E,A*07" in the middle of the above sample which is "overridden" immediately by "$GPRMC,,V,,,,,,,,,,N*53" removing all the information received again.

Before I add another work around for some poor data quality, please check the following item first: are there any GPS apps and/or "Helper" apps installed on your device? In case one of these is installed, to may add the above invalid sentences while no external GPS is connected... Just a theory.

Anyone else with a Moto X facing the same issues?

- Harry

[crazyxzer0]

Thanks for taking a look at the logs! I understand you have plenty of work so no problem!

The only GPS app I have installed is Family Locator.

https://play.google.com/store/apps/deta ... mapd&hl=en