Survey Mode; White Rabbit (Wr) Survey Mode - Safran WR-ZEN Series User Manual

5.1.4

Survey Mode

The survey mode provides the system with the capability to evaluate the syn-
chronization performance of different time references even though they are not
the active reference. It enables the possibility to compare different non-active
inputs (White Rabbit/1PPS/10MHz) with the current active reference or the local
oscillator when no other active references are available.
The survey mode configures the interfaces as if they were active timing sources,
except that the computed error (time difference) is not applied to the system
and thus, to the local oscillator.
The user can configure this mode in order to compare timing sources, using
another active timing source as ground truth. Thus, the offsets, delays and time-
specific parameters of the survey mode are computed regarding this reference.
The survey mode can be configured via web UI and CLI configuration.
5.1.4.1

White Rabbit (WR) survey mode

The WR survey mode allows a WR interface to measure all parameters computed
in a standard WR active port mode, but without syncing the internal system
clock. The interface will try to lock to a master WR reference, and all the para-
meters will be computed using the system clock as time base.
Survey Overview
The web user interface allows the user to have a wide view of all the parameters
regarding the current status of each White Rabbit/Grand Master interface by con-
sulting the section Overview -> White Rabbit or Overview -> External Reference
(GM) respectively. A prior survey configuration needs to be made in order to dis-
play these tables. To conduct a survey to obtain parameters:
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5 WR-ZEN Series User Manual Rev. v5.1
1. The device should be set in custom mode. We can activate such a mode by
accessing Configuration - > Timing General. Under the preset tab, select
Custom preset and click Apply.
2. Under Fanout Configuration, select Fanout Source #wr0 as MASTER and
Fanout Source #wr1 as SURVEY as seen in the following image:
5.1 Multi-sources & Resiliency
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