By enabling communication, data can be exchanged between the CMMT and the other network
devices. All status transitions are controlled by the commands from the higher-order controller. The
CMMT does not perform autonomous status changes.
The illustration shows all statuses and status transitions of the EtherCAT finite state machine.
Init
(Power ON)
(Reset)
Pre-Operational (PreOp)
Safe-Operational (SafeOp)
Operational (Op)
(OS)
(SO)
(OI)
(PI)
(IP)
(PS)
(OP)
(SI)
(SP)
Bootstrap (Boot)
(IB)
(IB)
Fig. 106 EtherCAT final state machine
The table describes all statuses of the EtherCAT final state machine.
Status
Status
Init
–
Status after Power ON or Reset.
–
acyclical mailbox communication (SDO) is not possible.
–
cyclical process data communication (PDO) is not possible.
–
the controller initialises Sync Manager channels 0 and 1 for mailbox
communication.
Pre-Operational
(PreOp)
–
acyclical mailbox communication (SDO) is possible.
–
cyclical process data communication (PDO) is not possible.
–
the controller initialises Sync Manager 2 and 3 and PDO mapping for
process data communication.
EtherCAT
521
Festo — CMMT-ST-SW — 2019-02
Summary of Contents for CMMT-ST-SW
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