Communication
What this chapter contains
This chapter describes the communication on an EtherCAT®
network.
EtherCAT® frame structure
In EtherCAT, the data between the master and the slaves is
transmitted in Ethernet frames. An EtherCAT® Ethernet frame
consists of one or several EtherCAT® telegrams, each addressing
individual devices and/or memory areas. The telegrams can be
transported either directly in the data area of the Ethernet frame or
within the data section of an UDP datagram transported via IP.
The EtherCAT® frame structure is pictured in following figure
EtherCAT® frame structure.
of an EtherCAT® header, the data area and a working counter,
which is incremented by all EtherCAT® nodes that are addressed
by the telegram and have exchanged associated data.
Figure 6. EtherCAT® frame structure.
Each EtherCAT® telegram consists
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Communication