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Format of the nmea 0183 string (rmc) – Meinberg SHSPZF LANTIME User Manual

Page 129

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Format of the NMEA 0183 String (RMC)

The NMEA String is a sequence of 65 ASCII characters starting with the ‘$’

character and ending with the characters CR (carriage return) and LF (line-feed). The
format is:

$GPRMC,hhmmss.ss,A,bbbb.bb,n,lllll.ll,e,0.0,0.0,ddmmyy,0.0,a*hh

The letters printed in italics are replaced by ASCII numbers or letters whereas the
other characters are part of the time string. The groups of characters as defined below:

$

start character (ASCII-Code 24h)
sending with one bit occuracy at change of second

hhmmss.ss

the current time:
hh

hours

(00..23)

mm minutes

(00..59)

ss

seconds

(00..59, or 60 while leap second)

ss

fractions of seconds

(1/10 ; 1/100)

A

Status

(A = time data valid)
(V = time data not valid)

bbbb.bb

latitude of receiver position in degrees
leading signs are replaced by a space character (20h)

n

latitude, the following characters are possible:
‘N’

north of equator

‘S’

south d. equator

lllll.ll

longitude of receiver position in degrees
leading signs are replaced by a space character (20h)

e

longitude, the following characters are possible:
‘E’

east of Greenwich

‘W’ west of Greenwich

ddmmyy

the current date:
dd

day of month

(01..31)

mm month

(01..12)

yy

year of the century

(00..99)

a

magnetic variation

hh

checksum (EXOR over all characters except ‘$’ and ‘*’)

carriage-return; ASCII-Code 0Dh

line-feed; ASCII-Code 0Ah

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