Verifying DGPS is on in the NEMA string

How do I verify that DGPS is turned on in a NEMA message?

I believe that the GGA message’s “Position Fix Indicator” is a 2 when DGPS is on. See page 1-2 and 1-3 of [this manual.

Cheers!

gm](http://www.sparkfun.com/datasheets/GPS/NMEA%20Reference%20Manual1.pdf)

Thanks! :smiley: