beautypg.com

1 ethercat-frames, Ethercat-frames, 7data transfer – Lenze E94AYCET User Manual

Page 55

background image

Lenze · E94AYCET communication module (EtherCAT®) · Communication Manual · DMS 9.0 EN · 02/2014 · TD17

55

7

Data transfer

7.1

EtherCAT-Frames

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

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