Lenze C520 - Addressing of the slaves

8.1.2 Addressing of the slaves
The EtherCAT system uses two types of addressing for the slaves:
1.
Auto-increment addressing
2.
Fixed-address addressing
Synchronizing the internal EtherCAT slave
The controller contains an internal EtherCAT slave with its own address to
provide the synchronizaon.
Thus, the connected rst nodes have the following start address:
•
0xFFFE by the auto-increment procedure
•
1002 by xed-address addressing
The addional internal slave is also to be taken into consideraon when running network
diagnoscs.
Auto-increment addressing
Auto-increment addressing is used by the master during the inializaon phase of the
eldbus. When the Pre-Operaonal state has been reached, the master uses xed-address
addressing.
Fixed-address addressing
With the xed-address addressing, the slaves are addressed via the staon address distributed
by the master during the start-up phase. In the EtherCAT bus topology in the »PLC Designer«,
the rst slave is given the address 1001, the second slave the address 1002 and so on. The
EtherCAT addresses cannot be changed. The EtherCAT address of the master is 0. Access to
master objects with the address 0 is possible.
Example of the auto-increment procedure and xed-address addressing
The rst slave of a conguraon is an internal slave and is given the following address:
•
Auto-increment procedure: 0
•
Fixed-address addressing procedure: 1001
The rst external slave of a conguraon is given the following addresses:
•
Auto-increment procedure: -1
•
Fixed-address addressing procedure: 1002
The auto-increment procedure uses negave numbering.
Conguring the network
EtherCAT
Addressing of the slaves
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