REFERENCE MANUAL - FTP Directory Listing - Trimble

C NMEA 0183
Field Definitions
Many of the NMEA data fields are of variable length, and the user should always use
the comma delimiter to parse the NMEA message date field. The table below
specifies the definitions of all field types in the NMEA messages supported by
Trimble.
Table C.2
Field Definitions
Type Symbol Definition
Status A Single character field:
A=Yes, data valid, warning flag clear
V=No, data invalid, warning flag set
Special Format Fields
Latitude llll.lll Fixed/variable length field:
Degreesminutes.decimal-2 fixed digits of degrees, 2 fixed
digits of minutes and a variable number of digits for
decimal-fraction of minutes. Leading zeros always included
for degrees and minutes to maintain fixed length. The
decimal point and associated decimal-fraction are optional if
full resolution is not required.
Longitude yyyyy.yyy Fixed/Variable length field:
Degreesminutes.decimal-3 fixed digits of degrees, 2 fixed
digits of minutes and a variable number of digits for
decimal-fraction of minutes. Leading zeros always included
for degrees and minutes to maintain fixed length. The
decimal point and associated decimal-fraction are optional if
full resolution is not required.
Time hhmmss.ss Fixed/Variable length field:
hoursminutesseconds.decimal-2 fixed digits of minutes, 2
fixed digits of seconds and a variable number of digits for
decimal-fraction of seconds. Leading zeros always included
for hours, minutes, and seconds to maintain fixed length.
The decimal point and associated decimal-fraction are
optional if full resolution is not required.
Defined
Some fields are specified to contain pre-defined constants,
most often alpha characters. Such a field is indicated in this
standard by the presence of one or more valid characters.
Excluded from the list of allowable characters are the
following that are used to indicated field types within this
standard:
“A”, “a”, “c”, “hh”, “hhmmss.ss”, “llll.ll”, “x”, “yyyyy.yy”
Numeric Value Fields
Variable x.x Variable length integer or floating numeric field. Optional
leading and trailing zeros. The decimal point and associated
decimal-fraction are optional if full resolution is not
required (example: 73.10=73.1=073.1=73).
Fixed HEX hh Fixed length HEX numbers only, MSB on the left
Information Fields
Fixed Alpha aa Fixed length field of upper-case or lower-case alpha
characters
Fixed number xx Fixed length field of numeric characters
214 Copernicus GPS Receiver