MANUAL P/N 900000015 REV 1.2
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4.5.1 Reference
The Reference consists of two fields, the Select reference and Reference Stable. The Select
reference allows the user to select one of the three references to acquire time from. The three
references used by the system are NTP Time Server, Serial Port Input, and GPS (optional).
The NTP Time Server reference uses the Network Time Protocol to synchronize the internal clocks
of a computer to the reference’s time. The stratum level may vary depending on the current
reference setting. To use this reference the NTP Server Address Pool must be setup.
The Serial Port Input reference continuously receives an update every second. The stratum level
for this reference is 2.
The serial time format is
[STS][DOW][%x20][DAY]/[MONTH]/[YEAR][%x20 %x20][HOUR]:[MINUTE]:[SECOND][%x0D]
.
The Serial Time Format Table lists the data and descriptions used.
Serial Time Format Table
DATA
DESCRIPTION
STS
Start of the message %x02 and this character acts as the 1PPS
timing mark
DOW
Day of the week written as three letters: Sun, Mon, Tue, Wed,
Thu, Fri, and Sat
%x20 Space
character
DAY
Two digit number of the day (01 - 31)
%x2F
Slash character '/'
MONTH
Two digit number of the month (01 - 12)
%x2F
Slash character '/'
YEAR
Two digit number of the year (00 - 99)
%X20 Space
character
%x20 Space
character
HOUR
Two digit number of the hour (00 - 23)
%x3A
Colon character ':'
MINUTE
Two digit number of the minute (00 - 59)
%x3A
Colon character ':'
SECOND
Two digit number of the second (00 – 59)
%x0D
End of message – carriage return
The optional GPS reference uses a GPS receiver to synchronize the internal clocks. The stratum
level for this reference is 1. To use the optional GPS reference, the GPS option must be installed.
The Reference Stable may be either ‘TRUE’ or ‘FALSE’. It is ‘TRUE’ when the Network Time
Device has acquired time from a reference. It is ‘FALSE’ when the Network Time Device has yet to
acquire time from a reference.
