Omron NJ101-10 Series, User Manual

Page: 73 / 280

EC_CoESDORead/
EC_CoESDOWrite
IN
OUT
EtherCAT
IN
OUT
SDO data
PDO
data
SDO data
PDO
data
SDO communications:
When required
(from instruction or
Sysmac Studio)
Constant data exchange
(process data communications cycle)
Process data communications:
* Device variables for EtherCAT slaves
Axis Variables only for Servo Drive and encoder input slaves to which axes are allocated
Message communications (for SDO data)
Device
variables and
Axis Variables*
Cyclic communications (for PDO data)
EtherCAT communications
CPU Unit
Process Data Communications (PDO Communications)
PDO communications is used for constant data exchange between the master and slaves. It is called
"process data communications".
PDO data (i.e., I/O data that is mapped to PDOs) that is allocated in advance is input and output peri-
odically each EtherCAT process data communications cycle (i.e., the task period of primary periodic
task or priority-5 periodic task).
It is accessed from the NJ/NX-series CPU Unit in the following ways.
• With device variables for EtherCAT slave I/O
• With Axis Variables for Servo Drive and encoder input slaves to which an axis is allocated
Additional Information
You can use the priority-5 periodic task only with NX701 CPU Units.
SDO Communications
SDO communications are used to read and write specified slave data from the master when required.
This is called "SDO communications".
You can read/write the following specified slave data with the EC_CoESDORead (Read CoE SDO) in-
struction or the EC_CoESDOWrite (Write CoE SDO) instruction.
• SDO data in slaves (parameters, error information, etc.)
3 EtherCAT Communications
3-5
NJ/NX-series CPU Unit Built-in EtherCAT Port User's Manual (W505)
3-1 EtherCA
T Communications T
ypes and Settings
3
3-1-2
T
ypes of Communications