Manual revision 017
Appendix I: NMEA Navigation Device Message and Data Formats
SBE 33
46
Appendix I: NMEA Navigation Device
Message and Data Formats
Message 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>
DBT – Depth Below Transducer
Depth in fathoms, meters, and feet
$--DBT,xxxx.x,f,dddd.d,M,xxxx.x,F*hh<CR><LF>
DPT – Depth
Depth
$--DPT,dddd.d,xxxx.x,xxxx.x*hh<CR><LF>
Field Type
Symbol
Definition
Status
A
Single character field:
A = Yes, data valid, warning flag clear
V = No, data invalid, warning flag set
Latitude
llll.ll
Fixed/Variable length field:
degrees|minutes.decimal - 2 fixed digits of degrees, 2 fixed digits of minutes, 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.
a
N or S
Longitude
yyyyy.yy
Fixed/Variable length field:
degrees|minutes.decimal - 3 fixed digits of degrees, 2 fixed digits of minutes, 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.
b
E or W
Time
hhmmss.ss
Fixed/variable length field:
hours|minutes|seconds.decimal - 2 fixed digits each of hours, minutes, and seconds; 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.
Depth
dddd.d (see
note at right)
Depth below transducer in meters.
Note: Format can be dddd.d or ddd.d
Checksum
*
Optional Checksum Delimiter.
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.
x represents miscellaneous
parameters that are ignored by the
SBE 33.
<CR> is carriage return.
<LF> is line feed.
See the table below for definitions of
message parameters.
Seasave and SBE Data Processing
are compatible with NMEA depth
data in the data stream. NMEA
depth data can be decoded and
merged with CTD data only if NMEA
position data is also available.
Seasave supports acquisition of
data from a NMEA device connected
to the deck unit or connected directly
to the computer.
