Omron CJ1W-EIP21 Operation Manuals page 83

Device Variables for CJ-series Unit
A device variable for a CJ-series Unit is a variable with an AT specification to an I/O port. In the user
program, you can use device variables for a CJ-series Unit to access Configuration Units, such as the
EtherNet/IP Unit.
Refer to Specifying Device Variables for CJ-series Units on page 3-5 for information on assigning I/O
ports for device variables for CJ-series Units.
 I/O Ports
An I/O port is a logical interface that is used by the CPU Unit to exchange data with an EtherNet/IP
Unit or other Configuration Unit.
The names of I/O ports are defined in advance for each Unit model number and function.
I/O ports are automatically created when you create the Unit Configuration on the Sysmac Studio.
Refer to 3-2 Device Variables for the CJ-series Unit for information on the I/O ports that are defined
for the EtherNet/IP Unit.
There are two types of I/O ports for an EtherNet/IP Unit: I/O ports for operating data and I/O ports for
setup data.
 Operating Data
• Software Switches
Software switches for output from the CPU Unit to the EtherNet/IP Unit are provided, such as the
Tag Data Link Start Bit.
Software switch data is stored in the I/O ports for operating data that are assigned to the Ether-
Net/IP Unit.
From the user program, you can use a device variable for the CJ-series Unit to access the data or
manipulate the switch. The software switches are updated during I/O refreshing.
• Status
Status data for input from the EtherNet/IP Unit to the CPU Unit is provided, such as the Communi-
cations Status. Status data is stored in the I/O ports for operating data that is assigned to the Eth-
erNet/IP Unit.
From the user program, you can use a device variable for the CJ-series Unit to access the status
data.
The status data is updated during I/O refreshing.
 Setup Data
• IP Address Display/Setting Area
You normally set the setup data from the Edit Special Unit Settings Tab Page of the Sysmac Stu-
dio. You can also set the setup data from the user program by using the setup device variables for
the CJ-series Unit with AT specifications to the applicable I/O ports.
Setup data is stored in the I/O ports for setup data that is assigned to the EtherNet/IP Unit. The
setup data is backed up by a battery when the power supply is interrupted.
The data is transferred to the EtherNet/IP Unit to update it whenever the Controller is reset or the
EtherNet/IP Unit is restarted.
CJ-series EtherNet/IP Units Operation Manual for NJ-series CPU Unit (W495)
3 Assigning Device Variables for CJ-series Units
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