Note:
Select Two Step operation if the Operating Mode is unknown.
4.
Delay Mechanism
By default the 'DELAY MECHANISM' will be set to E2E which will set the delay mechanism to end to end as
defined in IEEE 1588v2-2008.
5.
Configure Priority Fields
The 'PRIORITY #1' field is not used by the G.8275.1 Alternate BMCA, so is not configurable for the G.8275.1
profile and thus will appear with a default value of 128.
The 'PRIORITY # 2' field is used by the alternate BMCA, in addition to two additional priority fields, the port
local priority and clock local priority fields. These parameters modify the automatic selection of server clocks in
PTP networks.
Priority 2
In the alternate BMCA selection process, the 'PRIORITY # 2' value is treated as the fouth most important
selection criteria below clock class, clock accuracy, and clock variance in order, much like the traditional PTP
BMCA except that the priority 1 field isn't considered.
Below the priority 2 field, the clock local priority and port local priority fields are compared.
Clock Local Priority
The 'CLOCK LOCAL PRIORITY' is applied to the local clock when it is compared to a foreign server. Setting
this to a lower value will give preference to the local clock over foreign servers. The input range is 1 to 255,
where 1 is the highest priority. The default setting is 128. This attribute is not used when operating as a
Grandmaster.
Modify these fields to achieve your desired BMCA outcome.
Port Local Priority
The 'PORT LOCAL PRIORITY' is applied to the Announce messages received on the port from a potential
server when comparing that potential server to the local clock or other potential servers. Setting this to a lower
value will give preference to foreign servers connected to this port. The input range is 1 to 255, where 1 is the
highest priority. The default setting is 128. This attribute is not used when operating as a Grandmaster.
6.
Configure Default Domain
Modify the 'DEFAULT DOMAIN' number if required, otherwise it is recommended that it is left as its default
value of '24'.
A domain consists of one or more PTP devices communicating with each other. By default, PTP aware
devices are configured with a domain of '0'. Changing the domain will cause only devices with the specified
domain to communicate using the PTP protocol. The input range is 24-43.
7.
Advertised Delay Request Interval
Provisioning
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2022 Microchip Technology Inc.
and its subsidiaries
Manual
DS00004572A-page 137
