Variables - Omron NA5-15*101 series Startup Manual

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Variables

A variable is a container to store the I/O data that is exchanged with external devices or temporary data
for internal processing.
In the HMI, all the operations such as exchanging I/O data with external devices or arithmetic process-
ing on data are performed with variables.
Therefore, it is possible to create an HMI application that does not depend on the memory addresses in
the hardware.
Each object on a page accesses a variable in the global variable table of the HMI as shown below.
Some variables are mapped to global variables in the Controller (external variables) and other variables
are not mapped (internal variables).
Page
Object
Subroutine Variables and Global Variables
A subroutine variable can be read and written only from within one subroutine. A global variable, how-
ever, can be read and written from everywhere in the project. The application that is described in this
guide defines the variables to access the pushbutton switches and lamps as global variables.
Data Types of Variables
The data type is an attribute that defines the format and range of values that a variable can express.
When a variable is defined, the data type must always be specified.
In an NA-series Programmable Terminal, you can use the same data types as those used in Visual
Basic. Refer to the NA-series Programmable Terminal Software User's Manual (Cat. No. V118) for
details.
NA-series Programmable Terminal Startup Guide (V120)
HMI
HMI Global Variable Table
Access
Variable: External Variable
new_Controller_0_SwGreen
Variable: External Variable
new_Controller_0_SwYellow
Access
Variable: External Variable
new_Controller_0_SwRed
Access
Variable: Internal Variable
abc
2 HMI Application Basics
Controller name in the project:
new_Controller_0
Controller Global Variables
Mapping
Variable
SwGreen
Variable
SwYellow
Variable
SwRed
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