SFA-5000 • SFA-10000 EtherCAT
TREE topology:
DAISY CHAIN with drop lines topology:
6.1.4 Line Termination
EtherCAT network needs no line termination because the line is terminated
automatically; in fact every Slave is able to detect the presence of downstream
Slaves.
An EtherCAT Slave is able to detect the presence of the signal in the outgoing
line (Port 0) or in the return line (Port 1).
If the Slave is not able to detect the signal in its return line then it closes the
communication ring by short-circuiting the TX signal of its outgoing line with
the RX signal of its return line; in this way a telegram received through the
outgoing line is processed and sent back through the TX of the return line.
The Slave sends a “carrier signal” or a telegram on TX of the outgoing line
continuously and, once the next Slave is connected again, a signal on RX of the
return line is detected again; so the short circuit is removed and the telegrams
are sent on TX of the outgoing line.
MAN SFA_5000_10000_EC E 1.0.odt
6 - EtherCAT® interface
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