Data types, Variables, Groups – Rockwell Automation T6200 Compressor Anti-Surge and Capacity Controller User Manual

Page 140: Data type, Naming a variable

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Configuration

8-20


Begin cycle
| exchange I/Os
|

execute first program

|

...

|

execute last program

| wait for cycle time to be elapsed
End Cycle

Programs are executed according to the order defined by the user. The number of programs in an
application is limited to 255.

Programs must have unique names. The name cannot be a reserved keyword of the programming
languages and cannot have the same name as a standard or "C" function or function block. A
program should not have the same name as a declared variable. The name of a program should
begin by a letter or an underscore ("_") mark, followed by letters, digits or underscore marks. It is
not allowed to put two consecutive underscores within a name. Naming is case insensitive. Two
names with different cases are considered as the same.

Data Types

Below are the available basic data types. Although Straton supports more data types, use only the following three data types
when creating configurations for the ICS TRIPLEX controllers.

BOOL

DINT

REAL

STRING

Boolean (bit) - can be FALSE or TRUE - stored on 1 byte

Signed integer on 32 bits (from -2147483648 to +2147483647)

Single precision floating point - stored on 32 bits

Variable length string with declared maximum length of 255 characters


Variables

All variables used in programs must be first declared in the variable editor. Each variable belongs
to a group and must be identified by a unique name within its group.

Groups

A group is a set of variables. A group identifies the variables local to a program. Below are the
possible groups:

GLOBAL

Internal variables known by all programs in this project

PROGRAMxxx

All internal variables local to a program
(the name of the group is the name of the program)

Data type

Each variable must have a valid data type. It must be a basic data type

Refer to the list of available data types for more information.

Naming a variable

A variable must be identified by a unique name within its parent group. The variable name cannot
be a reserved keyword of the programming languages and cannot have the same name as a
standard or "C" function or function block. A variable should not have the same name as a
program.

The name of a variable should begin by a letter or an underscore ("_") mark, followed by letters,
digits or underscore marks. It is not allowed to put two consecutive underscores within a variable
name. Naming is case insensitive. Two names with different cases are considered as the same.

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