Omron CJ1W-ECT21 Operation Manual page 65

User program
Unit Status,
Slave Status
Device variable
AT specification
for CJ-series
Unit
I/O Communication
Area Setting and
Reference Tables
Device variable
AT specification
for CJ-series
Unit
I/O data
User-defined
AT specification
variable
*1. The setting results are exchanged when the CPU Unit is powered ON or when the Unit is restarted.
Device Variables for CJ-series Units
Device variables for CJ-series Units are variables for which AT is specified for the I/O port explained
below. The user program uses device variables for CJ-series Unit to access the configuration Unit such
as EtherCAT Slave Unit.
Refer to How to Create Device Variables for CJ-series Unit on page 3-5 for allocation of the device vari-
ables for CJ-series Unit to the I/O port.
 I/O Port
An "I/O port" is a logical interface for data exchange by a CPU Unit with an EtherCAT Slave Unit or
other configuration Unit.
An I/O port has a unique pre-defined name for each unit model and function.
An I/O port is automatically created by preparing the Unit configuration with Sysmac Studio.
Refer to 3-2 Device Variables for CJ-series Unit (Status) on page 3-9 and 3-3 Device Variables for
CJ-series Unit (I/O Communication Area Setting) on page 3-18 for details on the I/O ports defined
for the EtherCAT Slave Unit.
CJ-series EtherCAT Slave Units Operation Manual for NJ-series CPU Unit (W542)
CPU Unit
I/O port
Unit Status,
Slave Status
:
:
I/O Communication
Area Setting and
Reference Tables
:
:
Memory used for
CJ-series Unit
Memory areas such as
CIO and DM
:
:
3 Data Exchange with the CPU Unit
Unit/Slave status
(I/O refresh)
I/O Communication Area
Setting Table
(I/O refresh *1 )
I/O Communication Area
Reference Table
(Power ON or restart the Unit)
Input data
(I/O refresh)
Output data
(I/O refresh)
EtherCAT Slave Unit
:
:
3
:
:
:
:
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