A typical NMEA 0183 sentence looks like this: $GPGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,,*47
Reality: NMEA defines both electrical and data formats. A device might output NMEA-like strings at 5V TTL without RS-422 drivers—this is not fully compliant. Nmea 0183 Version 4.11 Pdf-
Once you have the PDF, study Part IV closely, build a small test harness with an Arduino or Raspberry Pi, and validate your sentences against the checksum examples. You will quickly see why this standard has stood the test of time. A typical NMEA 0183 sentence looks like this: