Trimble Outdoors 58052-00 Benutzerhandbuch

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C      NMEA 0183
2 1 4      Copernicus GPS Receiver
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