Basics
EK1122, EK15xx
40
Version: 3.4
Boot
In the
Boot
state the slave firmware can be updated. The
Boot
state can only be reached via the
Init
state.
In the
Boot
state mailbox communication via the
file access over EtherCAT
(FoE) protocol is possible, but no
other mailbox communication and no process data communication.
4.6
CoE - Interface: notes
This device has no CoE.
Detailed information on the CoE interface can be found in the
on the
Beckhoff website.
4.7
EKxxxx - Optional Distributed Clocks support
Basic principles Distributed Clocks (DC)
The EtherCAT Distributed Clocks system comprises local clocks that are integrated in the EtherCAT slaves
and are synchronized by the EtherCAT master via special datagrams. Not all EtherCAT slaves support the
Distributed Clocks procedure. It is only supported by slaves whose function requires it. In the TwinCAT
System Manager a slave indicates its DC capability by showing “DC” in the settings dialog.
Fig. 31:
DC tab for indicating the Distributed Clocks function
Once of these local clocks is the reference clock, based on which all other clocks are synchronized. See also
explanatory notes in the
. The reference clock must be the first DC-capable
EtherCAT slave. By default TwinCAT therefore selects the first DC-capable device as reference clock. This is
shown (and can be modified by the user) under advanced properties of the EtherCAT master. The standard
setting should not be changed, except in cases where external synchronization is recommended in the
relevant documentation, for example.
Fig. 32:
Advanced Distributed Clocks settings in the EtherCAT master
The figure shows how TwinCAT selects the EL1252 as reference clock by default, since the preceding
components do not support DC.
