Exchanging Data With The Cpu Unit - Omron CJ Series Operation Manual

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Exchanging Data with the CPU Unit

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Exchanging Data with the CPU Unit

Overview of Data Exchange
The CPU Unit and Analog I/O Unit exchange data, such as Operation Data and initial settings
parameters, via I/O ports created for Analog I/O Units or as necessary via the memory used for CJ-
series Units.
The following table shows the data exchange method for each data type.
• Data exchange type
Unit data type
Operation Data
Expansion Operation
data
Setting parameter 1
Setting parameter 2
Expansion setting param-
eter *2
Unit restart flag, etc.
*1 The setting parameters are retained in the CPU unit by the battery even during power interruptions.
*2 The CJ1W-AD04U has no expansion setting parameter.
Whether or not expansion setting parameters are retained even during power interruptions depends on the AT
specification area specification.
Device Variables for CJ-series Unit
Device variables for CJ-series Unit are variables used for data exchange between a user program and
Special I/O Units. The user program uses device variables for CJ-series Units to control the Analog I/O
Unit. Use device variables for CJ-series Units with AT specification for the I/O port, which is explained
below.
I/O port
An "I/O port" is a logical interface to enable the CPU Unit to exchange data with configuration units
such as the Analog I/O Unit.
An I/O port has a unique predefined name for each unit model and function.
An I/O port is automatically created by preparing the unit configuration with Sysmac Studio.
How to specify device variables for CJ-series Units
Allocate variables for CJ-series Unit to an I/O port from I/O map in the Sysmac Studio.
Specify the variable name for the AT specification with the following method.
1. Select a variable already registered in the variable table
2. Input a new variable name
3. Automatically create a variable name with "Device variable creation"
CJ-series Analog I/O Units Operation Manual for NJ-series CPU Unit(W498)
Access methods from a
user program
Device variable for CJ- I/O port (operation data)
series Unit
User-defined variables Memory used for CJ-
series Unit
Device variable for CJ- I/O port (setting parame-
series Unit ters) *1
User-defined variables Memory used for CJ-
series Unit
System-defined variables None
1 Overview and Features
AT specification
Data exchange timing
destination
During I/O refresh
When the Controller is
reset or the unit is
restarted
During I/O refresh
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