Lenze I/O system 1000 - Ethercat Datagrams; Ethercat State Machine

7 EtherCAT communication
7.1 About EtherCAT
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Lenze · I/O system 1000 · Reference Manual · DMS 5.0 EN · 09/2016 · TD17
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7.1.2 EtherCAT datagrams
EtherCAT datagrams have the following structure:
7.1.3 EtherCAT state machine
Each fieldbus node is lead through a status machine by the master. The changes of the bus states
are displayed in the following illustration.
header Data WKC
10 bits Max. 1486 bytes
2 bytes
WKC = Working Counter
Status Description
Init • No communication on the "Application Layer"
• The master can access the "DL-Information Register".
Pre-Operational • Mailbox communication on the "Application Layer"
• No process data communication
Safe-operational • Mailbox communication on the "Application Layer"
• Process data communication (only the inputs are evaluated, the outputs
are in the "safe" status.)
Operational • Inputs and outputs are evaluated.