Difference between GPGGA and XGPS fix

RE: Difference between GPGGA and XGPS fix

dejans — Fri, 25 Jul 2025 13:20:25 GMT

Hi,

Thank you for the update.

Best regards,
Dejan

HesselM — Thu, 24 Jul 2025 13:15:03 GMT

My bad! I've searched on all the wrong terms i guess.

For completeness, to compute PVT from NMEA:

GPGGA format:

$GPGGA,hhmmss.ss,lat,NS,lon,EW,fix,sats,hdop,alt,units,sep,units,diff_age,diff_station*cs

Latitude format is "ddmm.mmmmm", calculation: latitude = dd + (mm.mmmmm / 60)

Longitude format is "dddmm.mmmmm", calculation: longitude = ddd + (mm.mmmmm / 60)

For: "$GPGGA,122443.05,5223.40408,N,00454.22055,E,1,01,100.00,67.89,M,,M,,*4E"

this gives:
- latitude: 52 + (23.40408/60) ≈ 52.39007°N

- longitude: 4 + (54.22055/60) ≈ 4.90368°E

Which matches with the PVT.

Turbo J — Thu, 24 Jul 2025 12:14:55 GMT

Re-read the GPS specs, the output format is a bit different between GPGGA and XGPS. You cannot simply shift the comma decimal point.