RX72M Group
Single-Chip Motor Control via EtherCAT Communications
R01AN5434EJ0110 Rev.1.10
Page 18 of 85
Aug.31.2020
3. CiA402 Drive Profile
The CiA402 drive profile is the device profile for drivers and motion controllers and mainly defines functional
operations for servo drives, sine wave inverter, and stepping motor controller. In this profile, the multiple
operating modes and corresponding parameters are defined as an object dictionary. Moreover, the finite
state automaton (FSA) to define the internal and external behavior in every state is included. To change the
status, set the control word object, then status word which shows the current status reflects the result after
transition. The control word and various command values (such as for velocity) are assigned to RxPDO, and
the status word and various actual values (such as for position) are assigned to TxPDO. For details, refer to
the CiA402 Specifications.
Figure 3-1 Flow of CiA402 Communications
PLC
AC servo unit
RxPDO
Operation commands
and target values
TxPDO
State of operation and
current position
Cyclic communications