Rockwell Automation FactoryTalk View Site Edition Users Guide - Manual (Page 649)

A • F ACTORY T ALK V IEW COMMANDS
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Substituting the current values for the tag placeholders in commands in the macro,
FactoryTalk View opens displays named Screen1 and Screen2, and then sets a tag named
Valve23 to its open state.
Example 2: Ensuring that the tag value is evaluated as expected
FactoryTalk View evaluates tag placeholders before commands are run. For example, if
the press action for a button object is:
Tag1=4
Display Screen$Tag1$
when the button is pressed, the value of Tag1 will be substituted for the tag placeholder in
the Display command before Tag1 is set to 4.
To ensure that the tag is set first, embed the command containing the tag placeholder in
a macro that uses the tag as a parameter. Given a macro named Display_Detail, this would
change the button’s press action to:
Tag1=4
Display_Detail Tag1
Inside the macro, the tag placeholder is specified with the Display command, as follows:
Display Screen$%1$
Now when the button is pressed, FactoryTalk View will first set the tag to 4, and then run
the Display command in the macro, opening a display named Screen4.
Where commands run
Some commands run at the FactoryTalk View SE Server, some run at the FactoryTalk
View SE Client, and some run wherever they were issued.
If a tag placeholder is enclosed in double quotes (“ “) or nested in the string value of another tag
placeholder in the command, then FactoryTalk View will not substitute the tag value.