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With the FOR loop one can program repeated processes.

Syntax:

INT_Var :INT;
FOR <INT_Var> := <INIT_VALUE> TO <END_VALUE> {BY <Step size>} DO
  <Instructions>
END_FOR;

The part in braces {} is optional.

The <Instructions> are executed as long as the counter <INT_Var> is not greater than the <END_VALUE>. This is checked before executing the <Instructions> so that the <instructions> are never executed if <INIT_VALUE> is greater than <END_VALUE>.

When <Instructions> are executed, <INT_Var> is always increased by <Step size>. The step size can have any integer value. If it is missing, then it is set to 1. The loop must also end since <INT_Var> only becomes greater.

Example:

FOR Counter:=1 TO 5 BY 1 DO
Var1:=Var1*2;
END_FOR;
Erg:=Var1;

Let us assume that the default setting for Var1 is the value 1. Then it will have the value 32 after the FOR loop.

<END_VALUE> must not be equal to the limit value of the counter <INT_VAR>. For example: If the variable Counter is of type SINT and if <END_VALUE> is 127, you will get an endless loop.