A talker typically sends a group of sentences at intervals determined by the unit's update rate, but generally not more often than once per second.
Characters following the “*” are a checksum. Checksums are optional for most sentences, according to the standard.
Autopilot format B
APB,A,A,0.10,R,N,V,V,011,M,DEST,011,M,011,M
A Loran-C blink/SNR warning
A Loran-C cycle warning
0.10 cross-track error distance
R steer Right to correct (or L for Left)
N cross-track error units - nautical miles
V arrival alarm - circle
V arrival alarm - perpendicular
011,M magnetic bearing, origin to destination
DEST destination waypoint ID
011,M magnetic bearing, present position to destination
011,M magnetic heading to steer
(bearings could be given in True as 033,T)
(note: some pilots, Roberston in particular, misinterpret "bearing
from origin to destination" as "bearing from present position to
destination". This apparently results in poor performance if the
boat is sufficiently off-course that the two bearings are
different.)
Bearing - origin to destination waypoint
BOD,045.,T,023.,M,DEST,START
045.,T bearing 045 True from "START" to "DEST"
023.,M breaing 023 Magnetic from "START" to "DEST"
DEST destination waypoint ID
START origin waypoint ID
Bearing and distance to waypoint - great circle
BWC,225444,4917.24,N,12309.57,W,051.9,T,031.6,M,001.3,N,004*29
225444 UTC time of fix 22:54:44
4917.24,N Latitude of waypoint
12309.57,W Longitude of waypoint
051.9,T Bearing to waypoint, degrees true
031.6,M Bearing to waypoint, degrees magnetic
001.3,N Distance to waypoint, Nautical miles
004 Waypoint ID
Bearing and distance to waypoint - rhumb line
(format same as BWC)
Depth below transducer
DBT,0017.6,f,0005.4,M
0017.6,f 17.6 feet
0005.4,M 5.4 Metres
Global Positioning System Fix Data
GGA,123519,4807.038,N,01131.324,E,1,08,0.9,545.4,M,46.9,M, , *42
123519 Fix taken at 12:35:19 UTC
4807.038,N Latitude 48 deg 07.038' N
01131.324,E Longitude 11 deg 31.324' E
1 Fix quality: 0 = invalid
1 = GPS fix
2 = DGPS fix
08 Number of satellites being tracked
0.9 Horizontal dilution of position
545.4,M Altitude, Metres, above mean sea level
46.9,M Height of geoid (mean sea level) above WGS84
ellipsoid
(empty field) time in seconds since last DGPS update
(empty field) DGPS station ID number
Geographic position, Latitude and Longitude
GLL,4916.45,N,12311.12,W,225444,A
4916.46,N Latitude 49 deg. 16.45 min. North
12311.12,W Longitude 123 deg. 11.12 min. West
225444 Fix taken at 22:54:44 UTC
A Data valid
(Garmin 65 does not include time and status)
GPS DOP and active satellites
GSA,A,3,04,05,,09,12,,,24,,,,,2.5,1.3,2.1*39
A Auto selection of 2D or 3D fix (M = manual)
3 3D fix
04,05... PRNs of satellites used for fix (space for 12)
2.5 PDOP (dilution of precision)
1.3 Horizontal dilution of precision (HDOP)
2.1 Vertical dilution of precision (VDOP)
DOP is an indication of the effect of satellite geometry on
the accuracy of the fix.
Satellites in view
GSV,2,1,08,01,40,083,46,02,17,308,41,12,07,344,39,14,22,228,45*75
2 Number of sentences for full data
1 sentence 1 of 2
08 Number of satellites in view
01 Satellite PRN number
40 Elevation, degrees
083 Azimuth, degrees
46 Signal strength - higher is better
<repeat for up to 4 satellites per sentence>
There my be up to three GSV sentences in a data packet
Heading, Magnetic
HDM,235.,M
HDM Heading, Magnetic
235.,M Heading 235 deg. Magnetic
(HDG, which includes deviation and variation, is recommended
instead)
Command heading to steer
HSC,258.,T,236.,M
258.,T 258 deg. True
236.,M 136 deg. Magnetic
Water temperature, Celcius
MTW,11.,C
11.,C 11 deg. C
List of waypoint IDs in currently active route
R00,MINST,CHATN,CHAT1,CHATW,CHATM,CHATE,003,004,005,006,007,,,*05
(This sentence is produced by a Garmin 65, but is not listed
in Version 2.0 of the standard. The standard lists RTE for
this purpose.)
Recommended minimum navigation information (sent by nav. receiver when a destination waypoint is active)
RMB,A,0.66,L,003,004,4917.24,N,12309.57,W,001.3,052.5,000.5,V*0B
A Data status A = OK, V = warning
0.66,L Cross-track error (nautical miles, 9.9 max.),
steer Left to correct (or R = right)
003 Origin waypoint ID
004 Destination waypoint ID
4917.24,N Destination waypoint latitude 49 deg. 17.24 min. N
12309.57,W Destination waypoint longitude 123 deg. 09.57 min. W
001.3 Range to destination, nautical miles
052.5 True bearing to destination
000.5 Velocity towards destination, knots
V Arrival alarm A = arrived, V = not arrived
*0B mandatory checksum
Recommended minimum specific GPS/Transit data
RMC,225446,A,4916.45,N,12311.12,W,000.5,054.7,191194,020.3,E*68
225446 Time of fix 22:54:46 UTC
A Navigation receiver warning A = OK, V = warning
4916.45,N Latitude 49 deg. 16.45 min North
12311.12,W Longitude 123 deg. 11.12 min West
000.5 Speed over ground, Knots
054.7 Course Made Good, True
191194 Date of fix 19 November 1994
020.3,E Magnetic variation 20.3 deg East
*68 mandatory checksum
Waypoints in active route
RTE,2,1,c,0,W3IWI,DRIVWY,32CEDR,32-29,32BKLD,32-I95,32-US1,BW-32,BW-198*69
2 two sentences for full data
1 this is sentence 1 of 2
c c = complete list of waypoints in this route
w = first listed waypoint is start of current leg
0 Route identifier
W3IWI... Waypoint identifiers
Water speed and heading
VHW,259.,T,237.,M,05.00,N,09.26,K
259.,T Heading 259 deg. True
237.,M Heading 237 deg. Magnetic
05.00,N Speed 5 knots through the water
09.26,K Speed 9.26 KPH
Relative wind direction and speed
VWR,148.,L,02.4,N,01.2,M,04.4,K
148.,L Wind from 148 deg Left of bow
02.4,N Speed 2.4 Knots
01.2,M 1.2 Metres/Sec
04.4,K Speed 4.4 Kilometers/Hr
Track made good and ground speed
VTG,054.7,T,034.4,M,005.5,N,010.2,K
054.7,T True track made good
034.4,M Magnetic track made good
005.5,N Ground speed, knots
010.2,K Ground speed, Kilometers per hour
Waypoint Closure Velocity
Distance to Waypoint
Waypoint Distance, Rhumb Line
waypoint location
WPL,4917.16,N,12310.64,W,003*65
4917.16,N Latitude of waypoint
12310.64,W Longitude of waypoint
003 Waypoint ID
When a route is active, this sentence is sent once for each
waypoint in the route, in sequence. When all waypoints have
been reported, GPR00 is sent in the next data set. In any
group of sentences, only one WPL sentence, or an R00
sentence, will be sent.
Cross track error, measured
XTE,A,A,0.67,L,N
A General warning flag V = warning
(Loran-C Blink or SNR warning)
A Not used for GPS (Loran-C cycle lock flag)
0.67 cross track error distance
L Steer left to correct error (or R for right)
N Distance units - Nautical miles
Cross-Track Error - Dead Reckoning
XTR,0.67,L,N
0.67 cross track error distance
L Steer left to correct error (or R for right)
N Distance units - Nautical miles