nmea.txt

我在项目开发过程中搜集的各种NMEA协议文档

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 DBS - Depth Below Surface

        1   2 3   4 5   6 7
        |   | |   | |   | |
 $--DBS,x.x,f,x.x,M,x.x,F*hh<CR><LF>

 Field Number: 
  1) Depth, feet
  2) f = feet
  3) Depth, meters
  4) M = meters
  5) Depth, Fathoms
  6) F = Fathoms
  7) Checksum

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 DBT - Depth below transducer

        1   2 3   4 5   6 7
        |   | |   | |   | |
 $--DBT,x.x,f,x.x,M,x.x,F*hh<CR><LF>

 Field Number: 
  1) Depth, feet
  2) f = feet
  3) Depth, meters
  4) M = meters
  5) Depth, Fathoms
  6) F = Fathoms
  7) Checksum

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 DCN - Decca Position
                                      11  13      16
        1  2  3   4 5  6   7 8  9   10| 12| 14  15| 17
        |  |  |   | |  |   | |  |   | | | | |   | | |
 $--DCN,xx,cc,x.x,A,cc,x.x,A,cc,x.x,A,A,A,A,x.x,N,x*hh<CR><LF>

 Field Number: 
  1) Decca chain identifier
  2) Red Zone Identifier
  3) Red Line Of Position
  4) Red Master Line Status
  5) Green Zone Identifier
  6) Green Line Of Position
  7) Green Master Line Status
  8) Purple Zone Identifier
  9) Purple Line Of Position
 10) Purple Master Line Status
 11) Red Line Navigation Use
 12) Green Line Navigation Use
 13) Purple Line Navigation Use
 14) Position Uncertainity
 15) N = Nautical Miles
 16) Fix Data Basis
     1 = Normal Pattern
     2 = Lane Identification Pattern
     3 = Lane Identification Transmissions
 17) Checksum

(The DCN sentence is obsolete as of 3.01)

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 DPT - Depth of Water

        1   2   3
        |   |   |
 $--DPT,x.x,x.x*hh<CR><LF>

 Field Number: 
  1) Depth, meters
  2) Offset from transducer, 
     positive means distance from tansducer to water line
     negative means distance from transducer to keel
  3) Checksum

This sentence was incorrectly titled "Heading - Deviation & Variation"
in [NMEA2000].  It's documented at
<http://www.humminbird.com/normal.asp?id=853>

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DTM - Datum Reference

          1  2  3   4  5   6  7  8    9
          |  |  |   |  |   |  |  |    |
 $ --DTM,ref,x,llll,c,llll,c,aaa,ref*hh<CR><LF>

 Field Number: 
  1) Local datum code.  
  2) Local datum subcode.  May be blank.
  3) Latitude offset (minutes)
  4) N or S 
  5) Longitude offset (minutes)
  6) E or W
  7) Altitude offset in meters
  8) Datum name. What's usually seen here is "W84", the standard
     WGS84 datum used by GPS.
  9) Checksum.

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 FSI - Frequency Set Information

        1      2      3 4 5
        |      |      | | |
 $--FSI,xxxxxx,xxxxxx,c,x*hh<CR><LF>

 Field Number: 
  1) Transmitting Frequency
  2) Receiving Frequency
  3) Communications Mode (NMEA Syntax 2)
  4) Power Level
  5) Checksum

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GBS - GPS Satellite Fault Detection

            1      2   3   4   5   6   7   8   9
            |      |   |   |   |   |   |   |   |
 $--GBS,hhmmss.ss,x.x,x.x,x.x,x.x,x.x,x.x,x.x*hh<CR><LF>

 Field Number: 
  1) UTC time of the GGA or GNS fix associated with this sentence
  2) Expected error in latitude (meters)
  3) Expected error in longitude (meters)
  4) Expected error in altitude (meters)
  5) PRN of most likely failed satellite
  6) Probability of missed detection for most likely failed satellite
  7) Estimate of bias in meters on most likely failed satellite
  8) Standard deviation of bias estimate
  9) Checksum

Note: Source [MX521] describes a proprietary extension of GBS with
a 9th data field.
                                                      11
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GGA - Global Positioning System Fix Data
Time, Position and fix related data for a GPS receiver.

        1         2       3 4        5 6 7  8   9  10 |  12 13  14   15
        |         |       | |        | | |  |   |   | |   | |   |    |
 $--GGA,hhmmss.ss,llll.ll,a,yyyyy.yy,a,x,xx,x.x,x.x,M,x.x,M,x.x,xxxx*hh<CR><LF>

 Field Number: 
  1) Universal Time Coordinated (UTC)
  2) Latitude
  3) N or S (North or South)
  4) Longitude
  5) E or W (East or West)
  6) GPS Quality Indicator,
     0 - fix not available,
     1 - GPS fix,
     2 - Differential GPS fix
     (values above 2 are 2.3 features)
     3 = PPS fix
     4 = Real Time Kinematic
     5 = Float RTK
     6 = estimated (dead reckoning)
     7 = Manual input mode
     8 = Simulation mode
  7) Number of satellites in view, 00 - 12
  8) Horizontal Dilution of precision (meters)
  9) Antenna Altitude above/below mean-sea-level (geoid) (in meters)
 10) Units of antenna altitude, meters
 11) Geoidal separation, the difference between the WGS-84 earth
     ellipsoid and mean-sea-level (geoid), "-" means mean-sea-level
     below ellipsoid
 12) Units of geoidal separation, meters
 13) Age of differential GPS data, time in seconds since last SC104
     type 1 or 9 update, null field when DGPS is not used
 14) Differential reference station ID, 0000-1023
 15) Checksum

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 GLC - Geographic Position, Loran-C
                                           12    14
        1    2   3 4   5 6   7 8   9 10  11|   13|
        |    |   | |   | |   | |   | |   | |   | |
 $--GLC,xxxx,x.x,a,x.x,a,x.x,a.x,x,a,x.x,a,x.x,a*hh<CR><LF>

 Field Number: 
  1) GRI Microseconds/10
  2) Master TOA Microseconds
  3) Master TOA Signal Status
  4) Time Difference 1 Microseconds
  5) Time Difference 1 Signal Status
  6) Time Difference 2 Microseconds
  7) Time Difference 2 Signal Status
  8) Time Difference 3 Microseconds
  9) Time Difference 3 Signal Status
 10) Time Difference 4 Microseconds
 11) Time Difference 4 Signal Status
 12) Time Difference 5 Microseconds
 13) Time Difference 5 Signal Status
 14) Checksum

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 GLL - Geographic Position - Latitude/Longitude

	1       2 3        4 5         6 7   8
	|       | |        | |         | |   |
 $--GLL,llll.ll,a,yyyyy.yy,a,hhmmss.ss,a,m,*hh<CR><LF>

 Field Number: 
  1) Latitude
  2) N or S (North or South)
  3) Longitude
  4) E or W (East or West)
  5) Universal Time Coordinated (UTC)
  6) Status A - Data Valid, V - Data Invalid
  7) FAA mode indicator (NMEA 2.3 and later)
  8) Checksum

Introduced in NMEA 3.0.

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 GRS - GPS Range Residuals

              1    2  3  4  5  6  7  8  9 10 11 12 13 14  15
              |    |  |  |  |  |  |  |  |  |  |  |  |  |   |
 $ --GST,hhmmss.ss,m,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,*hh<CR><LF>

 Field Number: 
  1) TC time of associated GGA fix
  2) 0 = Residuals used in GGA, 1 = residuals calculated after GGA
  3) Satellite 1 residual in meters
  4) Satellite 2 residual in meters
  5) Satellite 3 residual in meters
  6) Satellite 4 residual in meters (blank if unused)
  7) Satellite 5 residual in meters (blank if unused)
  8) Satellite 6 residual in meters (blank if unused)
  9) Satellite 7 residual in meters (blank if unused)
  10) Satellite 8 residual in meters (blank if unused)
  11) Satellite 9 residual in meters (blank if unused)
  12) Satellite 10 residual in meters (blank if unused)
  13) Satellite 11 residual in meters (blank if unused)
  14) Satellite 12 residual in meters (blank if unused)
  15) Checksum

The order of satellites the same as those in the last GSA.

Example: $GPGRS,024603.00,1,-1.8,-2.7,0.3,,,,,,,,,*6C

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 GST - GPS Pseudorange Noise Statistics

              1    2 3 4 5 6 7 8   9
              |    | | | | | | |   |
 $ --GST,hhmmss.ss,x,x,x,x,x,x,x,*hh<CR><LF>

 Field Number: 
  1) TC time of associated GGA fix
  2) Total RMS standard deviation of ranges inputs to the navigation solution
  3) Standard deviation (meters) of semi-major axis of error ellipse
  4) Standard deviation (meters) of semi-minor axis of error ellipse
  5) Orientation of semi-major axis of error ellipse (true north degrees)
  6) Standard deviation (meters) of latitude error
  7) Standard deviation (meters) of longitude error
  8) Standard deviation (meters) of altitude error
  9) Checksum

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 GSA - GPS DOP and active satellites

	1 2 3                        14 15  16  17  18
	| | |                         |  |   |   |   |
 $--GSA,a,a,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x.x,x.x,x.x*hh<CR><LF>

 Field Number: 
  1) Selection mode
	       M=Manual, forced to operate in 2D or 3D
	       A=Automatic, 3D/2D
  2) Mode (1 = no fix, 2 = 2D fix, 3 = 3D fix)
  3) ID of 1st satellite used for fix
  4) ID of 2nd satellite used for fix
  ...
  14) ID of 12th satellite used for fix
  15) PDOP
  16) HDOP
  17) VDOP
  18) checksum

Robin Darroch writes: "As I understand it, DOP is unit-less, and can
only be compared meaningfully to other DOP figures.  A DOP of 4
indicates twice the likelihood of a given position error compared with
a DOP of 2.  The DOP is calculated from the expected errors due to
current geometry of the satellites used to obtain the fix.  The
estimated position errors should show a strong correlation with DOP,
but be completely different in value as they are measured in distance
units (i.e.  metres), and they are trying to tell you "you're very
probably within x metres of this point" rather than "I'm about twice
as sure of my position as I was a couple of minutes ago".

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 GSV - Satellites in view

These sentences describe the sky position of a UPS satellite in view.
Typically they're shipped in a group of 2 or 3.

	1 2 3 4 5 6 7     n
	| | | | | | |     |
 $--GSV,x,x,x,x,x,x,x,...*hh<CR><LF>

 Field Number: 
  1) total number of GSV messages to be transmitted in this group
  2) 1-origin number of this GSV message  within current group
  3) total number of satellites in view (leading zeros sent)
  4) satellite PRN number (leading zeros sent)
  5) elevation in degrees (00-90) (leading zeros sent)
  6) azimuth in degrees to true north (000-359) (leading zeros sent)
  7) SNR in dB (00-99) (leading zeros sent)
  more satellite info quadruples like 4-7
  n) checksum

Example:
    $GPGSV,3,1,11,03,03,111,00,04,15,270,00,06,01,010,00,13,06,292,00*74
    $GPGSV,3,2,11,14,25,170,00,16,57,208,39,18,67,296,40,19,40,246,00*74
    $GPGSV,3,3,11,22,42,067,42,24,14,311,43,27,05,244,00,,,,*4D

Some GPS receivers may emit more than 12 quadruples (more than three
GPGSV sentences), even though NMEA-0813 doesn't allow this.  (The
extras might be WAAS satellites, for example.) Receivers may also
report quads for satellites they aren't tracking, in which case the
SNR field will be null; we don't know whether this is formally allowed
or not.

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 GTD - Geographic Location in Time Differences

 	 1   2   3   4   5  6
	 |   |   |   |   |  |
 $--GTD,x.x,x.x,x.x,x.x,x.x*hh<CR><LF>

 Field Number: 
  1) time difference
  2) time difference
  3) time difference
  4) time difference
  5) time difference
  n) checksum

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 GXA - TRANSIT Position - Latitude/Longitude
 Location and time of TRANSIT fix at waypoint

        1         2       3 4        5 6    7 8
        |         |       | |        | |    | |
 $--GXA,hhmmss.ss,llll.ll,a,yyyyy.yy,a,c--c,X*hh<CR><LF>

 Field Number: 
 1) UTC of position fix
 2) Latitude
 3) East or West
 4) Longitude
 5) North or South
 6) Waypoint ID
 7) Satelite number
 8) Checksum

(The GXA sentence is obsolete as of 3.01.)

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 HDG - Heading - Deviation & Variation

        1   2   3 4   5 6
        |   |   | |   | |
 $--HDG,x.x,x.x,a,x.x,a*hh<CR><LF>

 Field Number: 
  1) Magnetic Sensor heading in degrees
  2) Magnetic Deviation, degrees
  3) Magnetic Deviation direction, E = Easterly, W = Westerly
  4) Magnetic Variation degrees
  5) Magnetic Variation direction, E = Easterly, W = Westerly
  6) Checksum

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 HDM - Heading - Magnetic

Vessel heading in degrees with respect to magnetic north produced by
any device or system producing magnetic heading.

        1   2 3
        |   | |
 $--HDM,x.x,M*hh<CR><LF>

 Field Number: 
  1) Heading Degrees, magnetic
  2) M = magnetic
  3) Checksum

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 HDT - Heading - True

Actual vessel heading in degrees true produced by any device or system
producing true heading.

        1   2 3
        |   | |
 $--HDT,x.x,T*hh<CR><LF>

 Field Number: 
  1) Heading Degrees, true
  2) T = True
  3) Checksum

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 HFB - Trawl Headrope to Footrope and Bottom

         1  2  3  4 5
         |  |  |  | |
 $--HFB,x.x,M,y.y,M*hh<CR><LF>

 Field Number: 
  1) Distance from headrope to footrope
  2) Meters (0-100)
  3) Distance from headrope to bottom
  4) Meters (0-100)
  5) Checksum

From [GLOBALSAT]. Shown with a "@II" leader rather than "$GP".

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 HSC - Heading Steering Command

        1   2 3   4  5
        |   | |   |  |
 $--HSC,x.x,T,x.x,M,*hh<CR><LF>

 Field Number: 
  1) Heading Degrees, True
  2) T = True
  3) Heading Degrees, Magnetic
  4) M = Magnetic
  5) Checksum

[GLOBALSAT] describes a completely different meaning for this
sentence, having to do with water temperature sensors.  It is 
unclear which is correct.

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 ITS - Trawl Door Spread 2 Distance

         1  2 3
         |  | |
 $--ITS,x.x,M*hh<CR><LF>

 Field Number)
  1) Second spread distance
  2) Meters
  3) Checksum.