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Last Modified: February 7, 2020

Enables the transmit of announce messages, which provide properties of this port as a potential grandmaster.

Announce messages are required for proper operation of the best master clock algorithm (BMCA), so this property is ignored when BMCA Enabled? is True.

Data type: datatype_icon

Long Name: Interface:Ethernet:Time Sync:Port:Announce Transmit Enabled?

Class: XNET Session

Permissions: Read/Write

When this property is True, the port transmits announce messages. This value is the default behavior as specified in the protocol standard.

When this property is False, the port does not transmit announce messages. When this property is False in the grandmaster, slave ports will not receive information about that grandmaster (e.g., properties such as Grandmaster Clock Accuracy). Therefore, the False value is useful for in-vehicle applications in which each slave assumes properties for its grandmaster as part of the vehicle's static design.

For the Protocol of IEEE Std 802.1AS-2011, a property value of True corresponds to announce message transmission as described in 10.3 of IEEE Std 802.1AS-2011. A property value of False is not specified in IEEE Std 802.1AS-2011. Behavior analogous to a property value of False is specified for 802.1AS as part of the AUTOSAR Specification of Time Synchronization over Ethernet, and the Avnu Automotive Ethernet AVB Functional and Interoperability Specification.

When an XNET session is started on a port that is set to Tap mode, this property becomes read only and its value cannot be modified.

Where This Property Is Available:

Desktop OS: Windows

FPGA: Not supported

Web Server: Not supported in VIs that run in a web application

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