EndRun Sonoma N12, User Manual

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S o n o m a U s e r M a n u a l 38
C H A P T E R F O U R
39 S o n o m a U s e r M a n u a l
P T P / I E E E - 1 5 8 8
The PTP Frequency Traceable indicator is either TRUE or FALSE. The Frequency Traceable is
TRUE if the Time Traceable is TRUE, otherwise it is FALSE.
About the PTP Second
and UTC Time
The PTP Time Mode selections are PTP and UTC. The IEEE-1588 standard defines the PTP epoch
beginning at 0 hours on 1 January 1970. The time measured since this epoch is designated in the
standard as PTP seconds. The PTP second is monotonic so does not include leap seconds.
Unlike PTP, the UTC second is not monotonic, that is, from time-to-time there will be leap second
insertions. The last second of a leap insertion day is 23:59:60 making the day one second longer than
a normal day ending at 23:59:59.
PTP Second
When the PTP Time Mode is set to PTP, the slave clocks must utilize the current leap second and leap
second pending flags (leap_59 or leap_61) to convert the PTP second to UTC.
UTC Time
When the PTP Time Mode is set to UTC, then there will be a one second jump in time when a leap
second insertion occurs. If the PTP slave does not account for this, it will also jump. Avoid this by
using PTP Time Mode.
Multiport PTP
When only one PTP option is enabled it will be configured for
eth0
PTP Domain 0. If a second PTP
option is enabled then it will be configured for
eth1
PTP Domain 1. This configuration will allow
PTP to run as master on both ports.
If the PTP Domain is configured as the same value for both ports (for example, PTP Domain 0 on
eth0
and PTP Domain 0 on
eth1
) then
eth0
Port State will be master and
eth1
Port State will be
listening.