• Provides an option to configure the EMAC to be a master or slave for ordinary and boundary clock.
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• Identifies the PTP message type, version, and PTP payload in frames sent directly over Ethernet and
sends the status.
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• Provides an option to measure sub-second time in digital or binary format.
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For more information about advanced timestamp features, refer to the
IEEE Standard 1588 - 2008 IEEE
Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems.
Related Information
IEEE Standards Association website
For more information on the IEEE standards, refer to the IEEE Standards Association website.
Peer-to-Peer PTP Transparent Clock (P2P TC) Message Support
The IEEE 1588-2008 version supports Peer-to-Peer PTP (Pdelay) messages in addition to SYNC, Delay
Request, Follow-up, and Delay Response messages.
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Clock Types
The EMAC supports the following clock types defined in the IEEE 1588-2008 standard:
• Ordinary clock
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• Boundary clock
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• End-to-End transparent clock
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• Peer-to-Peer transparent clock
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Reference Timing Source
The EMAC supports the following reference timing source features defined in the IEEE 1588-2008 standard:
• 48-bit seconds Field
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• Fixed pulse-per-second output
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• Flexible pulse-per-second output
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• Auxiliary snapshots (timestamps) with external events
Transmit Path Functions
The advanced timestamp feature is supported through the descriptors format.
Receive Path Functions
The MAC processes the received frames to identify valid PTP frames. You can control the snapshot of the
time, to be sent to the application, by using the following options:
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• Enable timestamp for all frames.
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• Enable timestamp for IEEE 1588 version 2 or version 1 timestamp.
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• Enable timestamp for PTP frames transmitted directly over Ethernet or UDP/IP Ethernet.
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• Enable timestamp snapshot for the received frame for IPv4 or IPv6.
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• Enable timestamp snapshot for EVENT messages (SYNC, DELAY_REQ, PDELAY_REQ, or
PDELAY_RESP) only.
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• Enable the node to be a master or slave and select the timestamp type. This controls the type of messages
for which timestamps are taken.
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The DMA returns the timestamp to the software inside the corresponding transmit or receive descriptor.
Ethernet Media Access Controller
Altera Corporation
cv_54017
Peer-to-Peer PTP Transparent Clock (P2P TC) Message Support
17-18
2013.12.30