Sea-Bird Electronics SBE 45 MicroTSG, Руководство пользователя

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Appendix I: NMEA Data SBE 45 Interface Box
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Appendix I: NMEA Data
NMEA Raw Message Formats
The Interface Box can interpret NMEA data from a NMEA navigation device
if the data is in one of the following formats:
GGA - Global Positioning System Fix Data
Time, position, and fix-related data for a GPS receiver.
$--GGA,hhmmss.ss,llll.ll,a,yyyyy.yy,b,x,xx,x.x,x.x,M,x.x,M,x.x,xxxx*hh<CR><LF>
GLL - Geographic Position - Latitude/Longitude
Latitude and Longitude of present position, time of position fix, and status.
$--GLL,llll.ll,a,yyyyy.yy,b,hhmmss.ss,A*hh<CR><LF>
RMA - Recommended Minimum Specific Loran-C Data
Position, course, and speed data provided by a LORAN-C receiver.
$--RMA,A,llll.ll,a,yyyyy.yy,b,x.x,x.x,x.x,x.x,x.x,a*hh<CR><LF>
RMC - Recommended Minimum Specific GPS/TRANSIT Data
Time, date, position, course, and speed data provided by a GPS or TRANSIT
navigation receiver.
$--RMC,hhmmss.ss,A,llll.ll,a,yyyyy.yy,b,x.x,x.x,ddmmyy,x.x,a*hh<CR><LF>
TRF - TRANSIT Fix Data
Time, date, position, and information related to a TRANSIT fix.
$--TRF,hhmmss.ss,ddmmyy,llll.ll,a,yyyyy.yy,b,x.x,x.x,x.x,x.x,xxx,A*hh<CR><LF>
where
Field Type Symbol Definition
Status A
Single character field:
A = Yes, data valid, warning flag clear
V = No, data invalid, warning flag set
llll.ll
Fixed/Variable length field:
degrees|minutes.decimal - 2 fixed digits of degrees, 2 fixed digits of minutes, and variable
number of digits for decimal-fraction of minutes. Leading zeros always included for degrees and
minutes to maintain fixed length. Decimal point and associated decimal-fraction are optional if
full resolution not required.
Latitude
a N or S
yyyyy.yy
Fixed/Variable length field:
degrees|minutes.decimal - 3 fixed digits of degrees, 2 fixed digits of minutes, and variable number
of digits for decimal-fraction of minutes. Leading zeros always included for degrees and minutes to
maintain fixed length. Decimal point and associated decimal - fraction optional if full resolution
not required.
Longitude
b E or W
Time hhmmss.ss
Fixed/variable length field:
hours|minutes|seconds.decimal - 2 fixed digits of hours, 2 fixed digits of seconds, and variable
number of digits for decimal-fraction of seconds. Leading zeros always included for hours,
minutes, and seconds to maintain fixed length. Decimal point and associated decimal-fraction
optional if full resolution not required.
* Optional Checksum Delimiter.
Checksum
hh
Optional Checksum Field:
Absolute value calculated by exclusive OR’ing 8 data bits (no start or stop bits) of each character
in message, between, but excluding
$ and * .
Notes:
•
-- represents two device-specific
characters.
•
See the table below for definitions
of message parameters.
•
<CR> is carriage return.
•
<LF> is line feed.
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