A couple of our favorite GPS-parsing Arduino libraries are TinyGPS and TinyGPS++. These libraries simplify the task of parsing the excessive NMEA strings, leaving us with just the few bits of data we care about.
You need to install the libraries on your own Arduino development machine, visit the links above to download them. Reference sparkfun’s Installing an Arduino Librarytutorial for any additional library-installing help you may need.
TinyGPS++ Example for NEO-6M only
Here’s a quick example, which uses the TinyGPS++ library to parse NMEA strings for position, altitude, time, and date. The code is also available in GPS Shield GitHub repository.
/****************************************************************************** This example uses SoftwareSerial to communicate with the GPS module on pins 8 and 9. It uses the TinyGPS++ library to parse the NMEA strings sent by the GPS module, and prints interesting GPS information to the serial monitor. After uploading the code, open your serial monitor, set it to 9600 baud, and #include <TinyGPS++.h> // Include the TinyGPS++ library #define GPS_BAUD 9600 // GPS module baud rate. GP3906 defaults to 9600. // If you’re using an Arduino Uno, Mega, RedBoard, or any board that uses the // Set gpsPort to either ssGPS if using SoftwareSerial or Serial1 if using an // Define the serial monitor port. On the Uno, Mega, and Leonardo this is ‘Serial’ void setup() void loop() // “Smart delay” looks for GPS data while the Arduino’s not doing anything else void printGPSInfo() // This custom version of delay() ensures that the tinyGPS object // printDate() formats the date into dd/mm/yy. // printTime() formats the time into “hh:mm:ss”, and prints leading 0’s |
You may need to adjust the gpsPort and SerialMonitor defines near the top of the sketch. As it is, the sketch is set up to use the SoftwareSerial port.
After uploading the code, open up your serial monitor to watch the parsed GPS data stream.
If your module doesn’t have a good GPS fix, you’ll probably see a lot of 0’s stream by; the time should be incrementing, although it’ll be incorrect (unless you plugged your Arduino in at exactly midnight!).
If you can find a way to take your computer and Arduino setup outside, that’ll be your best bet for getting a fix. Otherwise, try to take it near an open window. The better view it has of the sky, the better chance it’ll have to find the four satellites it needs.
A successful, fixed GPS stream will look something like this:
Lat: 40.090422 Long: -105.184534 Alt: 5243.77 Course: 295.56 Speed: 0.01 Date: 26/1/2016 Time: 20:19:34 Sats: 6 |
For more information on using the TinyGPS++ Library, check out the project homepage.