Clock class
Displays the current clock class of
OTMC 100
(see IEEE 1588-2008,
clause 7.6.2.4). The clock class is broadcast in the corresponding PTP
data packets. The value of the clock class parameter is automatically set
by
OTMC 100
depending on the source of time that is currently available:
PRIMARY_REF_PTP (6)
The clock of
OTMC 100
is locked to a primary reference time source, i.e.,
to the GPS system.
PRIMARY_REF_PTP_HOLDOVER (7)
The clock was previously locked to GPS time but has lost GPS reception.
The internal oscillator of
OTMC 100
is used as the source of time and
provides time with the accuracy given by the Clock accuracy parameter.
NOT_IN_SPEC_PTP_A (52)
The clock is not locked to GPS time and is not within its holdover
specification.
Clock accuracy
Displays the current accuracy of
OTMC 100
's internal clock with regard to
TAI. See IEEE 1588-2008, clause 7.6.2.5 for details. This parameter is
determined automatically by
OTMC 100
, considering the quality of the
current GPS reception.
Clock variance
Displays the clock variance. The clock variance parameter is set to the
PTP variance value specified by IEEE 1588-2008, clause 7.6.3. This
parameter gives a measure for the stability of the internal oscillator of
OTMC 100
and is used in the Best Master Clock Algorithm (BMCA) of the
PTP protocol. The clock variance of
OTMC 100
is set to a constant value
that was determined from laboratory observations.
Priority 1
Priority 2
Displays the priority values of
OTMC 100
. To each PTP master clock, two
priority values (Priority 1 and Priority 2) may be assigned by the user. If
more than one PTP grandmaster clock is available in the network, a clock
with a lower Priority 1 value will always be the preferred master clock over
a clock with a higher Priority 1 value (see IEEE 1588-2008, clause
6.6.2.3). A value in the range from 0 to 255 may be assigned to the Priority
1 parameter (see IEEE 1588-2008, clause 7.6.2.2).
The Priority 2 parameter (see IEEE 1588-2008, clause 7.6.2.3) is used if
several devices have the same Priority 1 parameter value and the same
clock quality (class, accuracy and variance). The Priority 2 parameter thus
allows a finer grained ordering among otherwise equivalent clocks (see
IEEE 1588-2008, clause 6.6.2.3). Lower values take precedence.
These parameters are set in the
Domain number
Displays the domain number of
OTMC 100
. The domain number specifies
the PTP domain (see IEEE 1588-2008, clause 7.1) in which
OTMC 100
participates. All clocks in a network that shall be synchronized to each
other must participate in the same PTP domain, i.e., have the Domain
number parameter set to the same value.
This parameter is set in the
Slave only
Displays whether the clock is a slave-only clock (true) or not (false). See
IEEE 1588-2008, clause 8.2.1.4.4.
The OTMC 100 web interface
OMICRON
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