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EtherCAT Information
TR-Electronic GmbH 2016, All Rights Reserved
Printed in the Federal Republic of Germany
Page 22 of 153
TR-EMO-BA-GB-0022 v03
09/29/2020
4.3.1 Transition into the OPERATIONAL state
INIT
The drive is initialized first of all and is then in INIT status. In this status, no direct
communication is possible between master and drive via the application layer. The
drive can be gradually transferred to OPERATIONAL status according to the state
machine via the EtherCAT master:
PRE-OPERATIONAL
The "Start Mailbox Communication" command puts the drive into PRE-
OPERATIONAL status. In this status only the mailbox is active first of all, and master
and drive exchange application-specific initializations and parameters. In PRE-
OPERATIONAL status only a parameterization via Service Data Objects is initially
possible. However, it is possible to configure PDOs using SDOs.
SAFE-OPERATIONAL
The "Start Input Update" command puts the drive into SAFE-OPERATIONAL status.
In this status the drive provides valid current input data, without changing the output
data. The outputs are in safe status.
OPERATIONAL
The "Start Output Update" command puts the drive into OPERATIONAL status. In this
status the drive provides valid input data and the master provides valid current output
data. When the drive has detected the data received via the process data service, the
status transition is confirmed by the drive. If activation of the output data was not
possible, the drive remains in SAFE-OPERATIONAL status and outputs an error
message.