RL-GNSS-001 · Navigation · KAMAL NAV GM1
NMEA output
Default GNSS sentence examples and first-pass filters for position and fix parsing.
Published May 4, 2026Updated May 9, 2026Reading time ~15 min
01Sentence stream#
The default ASCII stream uses GN talker IDs for multi-constellation output. Filter the sentences you need before parsing to reduce CPU and serial-buffer load.
$GNRMC,123519,A,4807.038,N,01131.000,E,022.4,084.4,230394,003.1,W*6A
$GNGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,,*47
$GNGSA,A,3,04,05,09,12,24,,,,,,,1.2,0.9,0.8,1*2702Useful filters#
$GNRMCfor recommended minimum navigation data$GNGGAfor fix quality, satellites, altitude, and HDOP$GNGSAfor active satellites and dilution values
03Parser guidance#
At higher fix rates, disable unused NMEA sentences or increase baud rate before flight testing. Sentence congestion usually looks like intermittent parser failures rather than a GNSS receiver fault.