326 appendix e – Leica Geosystems GPS System 500 - Technical Reference Manual User Manual
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326
Appendix E
Technical Reference Manual-4.0.0en
In the listing of NMEA messages, certain symbols are
used as identifier for the field types. They are:
Special Format Fields
A
Status
Single character field:
A = Yes, Data Valid, Warning Flag Clear
V = No, Data Invalid, Warning Flag Set
llll.ll
Latitude
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 are always included for degrees
and minutes to maintain fixed length.
yyyyy.yy
Longitude
Fixed / Variable length field:
degeesminutes.decimal - 3 fixed digits
of degrees, 2 fixed digits of minutes
and a variable number of digits for
decimal-fraction of minutes. Leading
zeros are always included for degrees
and minutes to maintain fixed length.
eeeeee.eee
Grid Easting
Fixed length field:
At the most 6 fixed digits for meters
and 3 fixed digits for decimal fractions
of meters.
nnnnnn.nnn
Grid Northing
Fixed length field:
At the most 6 fixed digits for meters
and 3 fixed digits for decimal fractions
of meters.
hhmmss.ss
Time
Fixed / Variable length field:
hoursminutesseconds.decimal - 2 fixed
digits of hours, 2 fixed digits of
minutes, 2 fixed digits of seconds and
a variable number of digits for decimal-
fraction of seconds. Leading zeros are
always included for hours, minutes
and seconds to maintain fixed length.
mmddyy
Date
Fixed length field:
monthdayyear - 2 fixed digits for
month, 2 fixed digits of day, 2 fixed
digits of year. Leading zeros always
included for month, day and year to
maintain fixed length.
Defined Field
Some fields are specified to contain
pre-defined constants, most often
alpha characters. Such a field is
indicated by the presence of one or
more valid characters. Excluded from
the list of allowable characters are the
following that are used to indicate
other field types: A, a, c, x, hh,
hhmmss.ss, llll.ll, yyyyy.yy.