Is anyone else having a problem with 1.8.2 and the course over ground, and speed over ground numbers when connecting your arduimu to a nmea gps? I tried a few different things, making sure it has not my hardware. No matter what I do, COG & SOG = 0.
If someone is having the same issue please let me know.
NMEA is considered old school to many of the people here and support is limited. It may not be fully debugged or may rely on a specific GPS's implementation of NMEA, not the real spec.
A quick look at the IMU 1.8.2 NMEA code show that it is trying to obtain speed and track from (only) the GPVTG message. (Several messages carry that information.)
Is your GPS sending this message? A lot don't (unless commanded to.)
The code should probably be modified to get speed and track from a more common message.