Relationship Between Process Data Communications Cycle And Motion Control Period - Omron NJ501-1400 User Manual

2-4-3 Relationship between Process Data Communications Cycle and
Motion Control Period
The PLC Function Module sends motion control commands to the MC Function Module when motion
control instructions are executed in the user program. The MC Function Module then performs motion
control processing based on those commands and sends the results of processing as commands to the
EtherCAT's Servo Drive.
This type of data exchange is updated as shown in the following processing period.
Primary period = Motion control period = Process data communications cycle
for EtherCAT communications
Execution of user
program in PLC
Function Module
Sequence control period
(primary periodic task)
NJ-series CPU Unit Motion Control User's Manual (W507)
2 Motion Control Configuration and Principles
CPU Unit
Motion control processing
by MC Function Module
Communications cycle
Motion control period
(EtherCAT data communi-
= Primary periodic
task period cations cycle = Primary
periodic task period)
Sequence control period
(primary periodic task period or
Basic I/O Units,
periodic task period)
Special I/O Units,
and CPU Bus Units
Processing in slave
EtherCAT
Data refresh
period in slave
(depends on
the slave)
Slaves
2-13
2