Lenze E94AYCET - Manual (Page 55)

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