8 Time Strings
8.8 Format of the NMEA 0183 String (ZDA)
The NMEA String is a sequence of 38 ASCII characters starting with the
‘$GPZDA’
character and ending with
the characters
CR
(carriage return) and LF (line-feed). The format is:
$GPZDA,
hhmmss.ss,dd,mm,yyyy,HH,II*cs
<CR><LF>
ZDA - Time and Date: UTC, day, month, year and local timezone.
The letters printed in italics are replaced by ASCII numbers or letters where as 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 accuracy at change of second
hhmmss.ss
the current UTC time:
hh
hours
(00..23)
mm
minutes
(00..59)
ss
seconds
(00..59 or 60 while leap second)
HH,II
the local timezone (offset to UTC):
HH
hours
(00..+-13)
II
minutes
(00..59)
dd,mm,yy
the current date:
dd
day of month
(01..31)
mm
month
(01..12)
yyyy
year
(0000..9999)
cs
checksum (EXOR over all characters except ‘$’ and ‘*’)
<CR>
Carriage Return, ASCII Code 0Dh
<LF>
Line Feed, ASCII Code 0Ah
SyncBox N2X
Date: 17th September 2019
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