Supported Devices
NMEA
Device Summary
GSatTrack accepts position reports as standard NMEA 0183 sentences from any GPS receiver, router or gateway that can connect over TCP and identify itself with a $GPSTN sentence. Use it for equipment that outputs NMEA but has no dedicated GSatTrack integration.
Peplink routers use their own GPS forwarding format instead; see Peplink Device Setup.
Register the Device
Create an asset with the device type NMEA before the device starts reporting. Enter the identifier the device sends in its $GPSTN sentence as the asset's unique identifier; the two must match exactly.
Reports are stored only for an active NMEA asset. Reports from an identifier with no matching asset are discarded, not held for later.
Server Settings
| Setting | Value |
|---|---|
| Server | protocolparser.com |
| Port | 4810 |
| Protocol | TCP |
Report Format
A report is a group of NMEA 0183 sentences, one per line: an identifying $GPSTN sentence followed by the position sentences.
Identifying Sentence
$GPSTN,{UniqueId}*hh
{UniqueId}is the identifier entered on the asset. Any fields after it, such as a device type or model, are ignored.*hhis the standard NMEA checksum.
Position Sentences
| Sentence | Required | Provides |
|---|---|---|
| RMC | Yes | Position, date and time, speed and course |
| GGA or GNS | No | Altitude, satellites in use and HDOP |
| GSA | No | PDOP and VDOP, and HDOP when no GGA or GNS is sent |
A report is not stored when its RMC sentence is missing or reports status V (no fix). Other sentences, such as GSV and VTG, are accepted and ignored.
Rules for Every Sentence
- End every sentence, including
$GPSTN, with*and its two-digit hexadecimal checksum. Sentences with a missing or incorrect checksum are discarded. - Any talker prefix is accepted:
$GP,$GN,$GLand$GAsentences are treated alike. - Write latitude as
ddmm.mmmmand longitude asdddmm.mmmm, zero-padded to two and three degree digits.
Example
A report for an asset with the unique identifier 1234567890:
$GPSTN,1234567890*73
$GPRMC,170500.00,A,3946.1234,N,10458.5678,W,12.4,87.0,140926,,,A*47
$GPGGA,170500.00,3946.1234,N,10458.5678,W,1,09,0.9,1609.3,M,-21.5,M,,*63
$GPGSA,A,3,02,05,12,15,18,21,25,29,31,,,,1.6,0.9,1.3*3A
Sending Reports
A device can open a connection, send one report and close it, or keep the connection open and start each new report with its own $GPSTN sentence. Every valid report is stored, so set the reporting interval on the device.