Rockwell Automation AutoMax Enhanced Ladder Editor User Manual

Page 65

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5Ć19

Tip
Selecting a variable from the Set Variables List fills the parameters

within the Current Selection group box with the information for the

variable.

5.12.2

Forcing Variables

To force a variable is to write a value to it that cannot be overĆwritten

by another program referencing the same variable. You can force

any simple global variable in the configuration or any simple local

variable present in a task that is loaded into the processor. Only

unforcing a variable permits it to be changed by a program or an

external device.
I

MPORTANT

You can force only simple variables. You cannot force

elementĆindexed or bitĆindexed variables. For example, you cannot

force variables like: vat.13, array_var[11], array_var[index_name],

array_var[11].12, or array_var[index_name].bit_name.

To force a variable
Step 1.

Make sure an online program window is open.

Step 2.

Do one of the following:

D Click on

or

D From the Online menu, choose Set/Force/Unforce.
The Set/Force/Unforce Variables dialog box is displayed.

You should keep this dialog box open while you are

setting, forcing, or unforcing multiple variables.

Step 3.

If you want to force a local variable, enter the name of the

program in which the variable is used in the Program

field. If you want to force a global variable, leave the field

blank.

Step 4.

Enter the name of the variable to be forced.
Only simple variables can be forced. The simple variable

selected before choosing the Set/Force/Unforce

command is the default. If no variable was selected, the

last variable forced is the default.

Step 5.

In the Value/State field, enter the value or state to force.
For Booleans, enter true, false, T, F, on, off, 1, or 0. You

can enter either decimal or hexadecimal values for

nonĆBoolean variables.

Step 6.

Select the force page (1Ć4) on which to store the variable

using the arrows in the Force Page field.
Specifying the force page lets you control how forced

variables are grouped. Variables grouped on one force

page can be unforced at the same time.

Step 7.

Click Force to force the variable.

Forced variables change to the color you specified on the Colors

tab. The default color for forced variables is red.

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