NMEA sentences was earlier identified by the initial strings $GPGGA and $GPRMC. That worked for the GPS receivers that was used during test. But there are other GPS receivers that uses $GNGGA and $GNRMC.
Code changed to check for GGA and RMC in position 4-6 instead.
A new python test script was added to find out where the problem was: test/gps_test.py
NMEA sentences was earlier identified by the initial strings $GPGGA and $GPRMC. That worked for the GPS receivers that was used during test. But there are other GPS receivers that uses $GNGGA and $GNRMC. Code changed to check for GGA and RMC in position 4-6 instead.
A new python test script was added to find out where the problem was: test/gps_test.py