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Figure 42. IGH EtherCAT master architecture
11.3 EtherCAT protocol
Following are the characteristics of the EtherCAT protocol:
• The EtherCAT protocol is optimized for process data and is transported directly within the standard IEEE 802.3 Ethernet
frame using Ethertype 0x88a4.
• The data sequence is independent of the physical order of the nodes in the network; addressing can be in any order.
• Broadcast, multicast, and communication between slaves is possible, but must be initiated by the master device.
• If IP routing is required, the EtherCAT protocol can be inserted into UDP/IP datagrams. This also enables any control with
Ethernet protocol stack to address EtherCAT systems.
• It does not support shortened frames.
The following figure shows the EtherCAT frame structure.
NXP Semiconductors
EtherCAT
Open Industrial User Guide, Rev. 1.8, 05/2020
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