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The following information describes some NMEA GPS sentences that are a little less widely used than the common NMEA GPS sentences. Many of these sentences are only used with high-end GPS and DGPS receivers and aren't available with low-cost GPS receivers.
| Sentence | Description |
| $GPALM | GPS almanac data |
| $GPGRS | GPS range residuals |
| $GPGST | GPS pseudorange noise statistics |
| $GPMSS | Beacon receiver status |
| $GPZDA | UTC and local date/time data |
| Field | Example | Comments |
| Sentence ID | $GPALM | |
| Number of messages | 1 | Total number of messages in sequence |
| Sequence number | 1 | This is first message in sequence |
| Satellite PRN | 15 | Unique ID (PRN) of satellite message relates to |
| GPS week number | 1159 | |
| SV health | 00 | Bits 17-24 of almanac page |
| Eccentricity | 441d | |
| Reference time | 4e | Almanac reference time |
| Inclination angle | 16be | |
| Rate of right ascension | fd5e | |
| Roor of semi-major axis | a10c9f | |
| Argument of perigee | 4a2da4 | |
| Longitude of ascension node | 686e81 | |
| Mean anomoly | 58cbe1 | |
| F0 clock parameter | 0a4 | |
| F1 clock parameter | 001 | |
| Checksum | *5B | |
| Terminator | CR/LF |
| Field | Example | Comments |
| Sentence ID | $GPGRS | |
| UTC Time | 024603.00 | UTC time of associated GGA fix |
| Mode | 1 | 0 = Residuals used in GGA, 1 = residuals calculated after GGA |
| Sat 1 residual | -1.8 | Residual (meters) of satellite 1 in solution |
| Sat 2 residual | -2.7 | The order matches the PRN numbers in the GSA sentence |
| Sat 3 residual | 0.3 | |
| Sat 4 residual | Unused entries are blank | |
| Sat 5 residual | ||
| Sat 6 residual | ||
| Sat 7 residual | ||
| Sat 8 residual | ||
| Sat 9 residual | ||
| Sat 10 residual | ||
| Sat 11 residual | ||
| Sat 12 residual | ||
| Checksum | *6C | |
| Terminator | CR/LF |
| Field | Example | Comments |
| Sentence ID | $GPGST | |
| UTC Time | 024603.00 | UTC time of associated GGA fix |
| RMS deviation | 3.2 | Total RMS standard deviation of ranges inputs to the navigation solution |
| Semi-major deviation | 6.6 | Standard deviation (meters) of semi-major axis of error ellipse |
| Semi-minor deviation | 4.7 | Standard deviation (meters) of semi-minor axis of error ellipse |
| Semi-major orientation | 47.3 | Orientation of semi-major axis of error ellipse (true north degrees) |
| Latitude error deviation | 5.8 | Standard deviation (meters) of latitude error |
| Longitude error deviation | 5.6 | Standard deviation (meters) of longitude error |
| Altitude error deviation | 22.0 | Standard deviation (meters) of latitude error |
| Checksum | *58 | |
| Terminator | CR/LF |
| Field | Example | Comments |
| Sentence ID | $GPMSS | |
| Signal strength | 0.0 | Signal strength (dB 1uV) |
| SNR | 0.0 | Signal to noise ratio (dB) |
| Frequency | 0.0 | Beacon frequency (kHz) |
| Data rate | 25 | Beacon data rate (BPS) |
| Unknown field | 2 | Unknown field sent by GPS receiver used for test |
| Checksum | *6D | |
| Terminator | CR/LF |
| Field | Example | Comments |
| Sentence ID | $GPZDA | |
| UTC Time | 024611.08 | UTC time |
| UTC Day | 25 | UTC day (01 to 31) |
| UTC Month | 03 | UTC day (01 to 12) |
| UTC Year | 2002 | UTC year (4 digit format) |
| Local zone hours | 00 | Offset to local time zone in hours (+/- 00 to +/- 59) |
| Local zone minutes | 00 | Offset to local time zone in minutes (00 to 59) |
| Checksum | *6A | |
| Terminator | CR/LF |