3 Common Slave Specifications
3 - 2 EtherCAT Communication Unit USER’S MANUAL (I574-E1)
3-1 Structure of CANopen over EtherCAT
The figure below shows the structure of CANopen over EtherCAT (CoE).
Normally, multiple protocols can be transmitted using EtherCAT. In the EtherCAT Communication Unit
for MX2/RX-V1 inverters, the CANopen communication profile (CiA 301) that is popular in Europe, and
the drive profile (CiA 402) are used.
The object dictionary in the application layer contains parameters and application data as well as infor-
mation on the PDO mapping between the process data and inverter application.
The process data object (PDO) consists of objects in the object dictionary that can be mapped to the
PDO. The contents of the process data are defined by the PDO mapping.
Process data communications cyclically reads and writes the PDO. Mailbox communications (SDO)
uses asynchronous message communications where all objects in the object dictionary can be read
EtherCAT data link layer
EtherCAT physical layer