Lenze I/O system 1000 System Manual - Manual (Page 481)

EtherCAT Kommunikation
About EtherCAT
EtherCAT datagrams
10
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481 EDSIO1000 EN 7.0
10.1.2 EtherCAT datagrams
EtherCAT datagrams have the following structure:
Header Data WKC
10 bits Max. 1486 bytes 2 bytes
WKC = Working Counter
10.1.3 EtherCAT state machine
Each fieldbus node is led through a state machine by the master. The state changes of the
bus are shown in the following illustration.
Status Description
Init l No communication on the "Application layer"
l The master has access to the "DL information register".
Pre−operation
al l Mailbox communication on the "Application layer"
l No process data communication
Safe−operatio
nal l Mailbox communication on the "Application layer"
l Process data communication (Only the inputs are evaluated; the outputs are in the "Safe"
status.)
Operational l Inputs and outputs are evaluated.