Lenze E84AYCET EtherCAT MCI module - Manual (Page 56)

7 Data transfer
7.2 EtherCAT datagrams
56
Lenze · E84AYCET communication module (EtherCAT) · Communication Manual · DMS 5.0 EN · 05/2013 · TD17
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
7.2 EtherCAT datagrams
Read and write accesses are always only executed in one small section of the complete EtherCAT
frame – the datagrams.
EtherCAT datagrams have the following structure:
EtherCAT Command header
The EtherCAT command header contains the following information:
• Command to be executed
• Addressing information
• Length of the data area (Data)
• Interrupt field
Data
The data area contains the data of the command to be executed.
WKC (Working Counter)
The working counter is evaluated by the master for monitoring the execution of the command.
EtherCAT
Command header
Data WKC
10 bytes Max. 1486 bytes 2 bytes