Getting GPS Data from AssetTracker Kit

I am getting GPS Data using the AssetTracker Kit and the AssetTraker Library. But the data format I get is only in GPGGA like this
$GPGGA,203554.000,5338.7632,N,01009.8577,E,1,3,54.51,104.1,M,45.9,M,*6,9, ,.P43,71831M
Why am I not retrieving data in GPRMC which is the recommended minimum specific GPS/Transit data? I have changed the following in the AssetTracker Library:

This still is not provinding the data in my expected RMC format. Has only one got the data in this format?


I’m experiencing the same problem as you. I need to get more info such as timestamp and validity but there is no GPRMC message. Hope that someone can help.

Yes, it’s somehow disappointing. I have tried a lot of options in the AssetTracker Library but nothing changes. I can’t get GPRMC sentence. Also each time I restart the device, it takes more than 25 minutes to get a fix although I am outdoor with an external antenna attached. I am wondering if the problem is with the software: Adafruit Library being used? I read that the GPS module on this AssetTracker is the same as the one on Fona SIM808 (a GSM+GPS Module) from Adafruit. But with the FONA we get a fix is always in less that 1 minutes indoor with an external antenna; also getting GPRMC sentence which gives us the speeds and timestamps we need for this project.
It would be great to hear if someone has actually succeeded to work effectively with this AssetTracker kit and it’s simply still in a trail phase!

@rlingeh, the Asset Tracker is compatible with other libraries such as TinyGPS (and ++ variant). As for getting a fix, I have experienced similar behavior with the unit placed indoors with a much lower fix time when it has a clear view of the sky. Using an external active antenna puts the shield on steroids and reduces fix times to seconds. Do you have the battery installed on the shield?

Hi @rlingeh
Definitely lots on this forum on the Asset Tracker (Search is your friend)
for example: Asset Tracker GPS -- Your experience with getting GPS fix

I managed to get the Asset Tracker working earlier this year.
Though to make getting a fix in any reasonable time I bought an active GPS antenna (like lots of others).
This seems to be almost essential for the GPS to work reliably and quickly.

The other thing I found useful, and seemed to help solve some of the problems you seem to be having too, was to switch to the TinyGPS library (made able to work in our Particle devices by @krvarma). Find details at TinyGPS and Spark Core.

These two changes made the Asset Tracker work for me, hope this helps.
NB: I am pretty sure I was able to get the NMEA sentences to be adjustable between the TinyGPS options of “GPRMC” and “GPGGA”.

This thread contains some good stuff on problems with the Adafruit library - and in particular on the issues around the NMEA sentence structure changeover: Default example for Asset Tracker GPS prints erratic NMEA sentences to serial


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Yes, we ordered the AssetTracker together with the battery. I will try the TinyGPS Library mentioned here by GreyMonkey. It may help solve some of the issues I am facing