Trimble PTNL GGK datagram format

PTNL GGK is a proprietary datagram from Trimble (https://www.trimble.com). It is longer than the standard NMEA GGK datagram. The PTNL GGK datagram is used to decode the time, position, type and dilution of precision of the current position.

Format

$--GGK,hhmmss.ss,ddmmyy,nnnnn.nnnnnnnn,a,yyyyy.yyyyyyyy,a,x,zz,w.w,EHTeeeeee,u*hh<CR><LF>

Format

$PTNLGGK,hhmmss.ss,ddmmyy,dddmm.mmmmmmmm,a,dddmm.mmmmmmmm,a,x,zz,w.w,EHTaaa.bbb,M*hh

Description

$PTNL: Talker identifier

GGK: Datagram identifier

hhmmss.ss: Coordinated Universal Time (UTC) of the current position

ddmmyy: Day, month and year

dddmm.mmmmmmmm: Latitude (degrees)

a: Direction of latitude

N = North

S = South

dddmm.mmmmmmmm: Longitude (degrees)

a: Direction of longitude

E = East

W = West

x = GPS quality indicator

0: Fix not available or invalid

1: Autonomous GPS fix

2: RTK float solution

3: RTK fix solution

4: Differential, code phase only solution (DGPS)

5: SBAS solution – WAAS/EGNOS/MSAS

6: RTK float or RTK location 3D Network solution

7: RTK fixed 3D Network solution

8: RTK float or RTK location 2D in a Network solution

9: RTK fixed 2D Network solution

10: OmniSTAR HP/XP solution

11: OmniSTAR VBS solution

12: Location RTK solution

13: Beacon DGPS

zz = Number of satellites in use (00 - 12)

The number of satellites may be different from the number in view.

w.w = PDOP (Position dilution of precision)

EHTaaa.bbb = Ellipsoidal height of fix

M = ellipsoidal height is measured in metres

*hh = Checksum

Note

The PTNL GGK message is longer than the NMEA-0183 standard of 80 characters.

Even if a user-defined geoid model, or an inclined plane is loaded into the receiver, then the height output in the NMEA GGK string is always an ellipsoid height, for example, EHT24.123.