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How do you group variables in Structured Text?

How do you group variables in Structured Text?
Say I have n global variables for lamps:

lamp1
lamp2
lamp3
... // and so on

Then I have a button, and pressing it should set all variables to TRUE:

IF buttonPressed Then
    lamp1 := TRUE;
    lamp2 := TRUE;
    lamp3 := TRUE;
    ... // and so on
END_IF

How can I group the lamps in a way to not to have to set every varriable to TRUE manually?

Solution

  • To set multiple variables at once, you would first have to collect the values you want to set in an array:

    VAR 
    lamp1 : BOOL;
    lamp2 : BOOL;
    lamp3 : BOOL;
    lamps : ARRAY[1..3] OF BOOL := [lamp1, lamp2, lamp3];
END_VAR

    and then set the values in a for loop.

    FOR i := 1 TO 3 DO
    lamps[i] := TRUE;
END_FOR

    Result

    enter image description here

    Function

    You can also define a custom function if you have to do it a lot:

    FUNCTION SetAllBools : BOOL
VAR_IN_OUT
    bools : BOOL;
END_VAR
VAR_INPUT
    newValue : BOOL;
END_VAR
VAR
    i : INT;
END_VAR

    which can then be used as SetAllBool(lamps, TRUE);.