Lenze · E94AYCET communication module (EtherCAT®) · Communication Manual · DMS 10.2 EN · 11/2018 · TD06
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7
Data transfer
7.1
EtherCAT telegrams
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7.1
EtherCAT telegrams
An EtherCAT telegram is based on a standard Ethernet frame with the Ether type ’0x88A4’ and has
the following structure:
Ethernet header
The Ethernet header contains the following information:
• Target address of the EtherCAT telelgram (destination)
• Source address of the EtherCAT telegram (source)
• Type of the EtherCAT telegram (Ether type = 0x88A4)
Ethernet data
The Ethernet data contain the following information:
• Length of the datagram within the EtherCAT telegram (length)
• One reserved bit (Reserved)
• Type of the datagrams within the EtherCAT frame (type)
• Datagrams
FCS
Checksum of the EtherCAT frame
Ethernet header
Ethernet data
FCS
48 bits
48 bits
16 bits
11 bits
1 bit
4 bits
48 ... 1498 bytes
32 bits
Destination
Source
Ether type
Frame header
Datagrams
Length
Reserved
Type