1 ethercat-frames, Ethercat-frames, 7data transfer – Lenze E94AYCET User Manual
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Lenze · E94AYCET communication module (EtherCAT®) · Communication Manual · DMS 9.0 EN · 02/2014 · TD17
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7
Data transfer
7.1
EtherCAT-Frames
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7.1
EtherCAT-Frames
EtherCAT frames have the following structure:
Ethernet header
The Ethernet header contains the following information:
• Target address of the EtherCAT frame (destination)
• Source address of the EtherCAT frame (source)
• Type of the EtherCAT frame (EtherType = 0x88A4)
Ethernet data
The Ethernet data contain the following information:
• Length of the datagrams within the EtherCAT frame (Length)
• One reserved bit (Reserved)
• Type of the datagrams within the EtherCAT frame (Type)
• EtherCAT datagrams (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
EtherType
Frame header
Datagrams
Length
Reserved
Type