Datasheet

Parsed Data Output

Since all GPS's output NMEA sentences and often for our projects we need to extract the actual data from them, we've

simplified the task tremendously when using the Adafruit GPS library. By having the library read, store and parse the

data in a background interrupt it becomes trivial to query the library and get the latest updated information without any

icky parsing work.

Open up the File→Examples→Adafruit_GPS→parsing sketch and upload it to the Arduino. Then open up the serial

monitor.

In this sketch, we call GPS.read() constantly in the main loop (if you can, get this to run once a millisecond in an

interrupt). Then in the main loop we can ask if a new chunk of data has been received by

calling GPS.newNMEAreceived(), if this returns true then we can ask the library to parse that data

with GPS.parse(GPS.lastNMEA()).

We do have to keep querying and parsing in the main loop - its not possible to do this in an interrupt because then

we'd be dropping GPS data by accident.

Once data is parsed, we can just ask for data from the library like GPS.day, GPS.month and GPS.year for the current

date. GPS.fix will be 1 if there is a fix, 0 if there is none. If we have a fix then we can ask

for GPS.latitude, GPS.longitude, GPS.speed (in knots, not mph or k/hr!), GPS.angle, GPS.altitude (in centimeters)

and GPS.satellites (number of satellites)

This should make it much easier to have location-based projects. We suggest keeping the update rate at 1Hz and

request that the GPS only output RMC and GGA as the parser does not keep track of other data anyways.