Ieee 1588-2002 Timestamps - Altera cyclone V Technical Reference

17-46
Receive Descriptor Field 7 (RDES7)
Receive Descriptor Field 7 (RDES7)
Table 17-17: Receive Descriptor Field 7 (RDES7)
Bit
31:0
Related Information
Receive Descriptor Field 0 (RDES0)

IEEE 1588-2002 Timestamps

The IEEE 1588-2002 standard defines the Precision Time Protocol (PTP) that enables precise synchroniza‐
tion of clocks in a distributed network of devices. The PTP applies to systems communicating by local area
networks supporting multicast messaging. This protocol enables heterogeneous systems that include
clocks of varying inherent precision, resolution, and stability to synchronize. It is frequently used in
automation systems where a collection of communicating machines such as robots must be synchronized
and hence operate over a common time base.
The PTP is transported over UDP/IP. The system or network is classified into Master and Slave nodes for
distributing the timing and clock information.
The following figure shows the process that PTP uses for synchronizing a slave node to a master node by
exchanging PTP messages.
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Synopsys expressly disclaims any and all warranties, express, implied, or otherwise, including the implied
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Altera Corporation
RTSH: Receive Frame Timestamp High
This field is updated by the DMA with the most significant 32 bits of the timestamp
captured for the corresponding receive frame. This field is updated by the DMA only for
the last descriptor of the receive frame, which is indicated by Last Descriptor status bit
(RDES0[8]) in RDES0.
Description
on page 17-37
(†)
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2016.10.28
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