REPEAT statement in ST

Syntax

REPEAT
  ...
UNTIL ...
END_REPEAT;

Meaning
Use the `REPEAT` statement to specify that a group of statements (entered after `REPEAT` up to `UNTIL`) is to be executed repeatedly (at least once) until the Boolean →expression (entered after `UNTIL`) evaluates to value `TRUE` (or an equivalent). If the expression initially evaluates to value `FALSE` (or an equivalent), then group of statements is executed exactly one time.

Example

FUNCTION_BLOCK ExampleRepeatDocumentation
  VAR
    count, sum, I : INT;
  END_VAR
  
  count := 1;
  sum := 0;
  REPEAT
    sum := ADD(sum, count);
    count := ADD(count, 1);
  UNTIL GT(count, 10)
END_REPEAT;                (* The variable 'sum' equals '45'. *)
END_FUNCTION_BLOCK

No identification of infinite loops

Infinite loops are not identified and prevented by logi.CAD 3. Therefore, enter code in your application to prevent infinite loops (e.g. abort conditions by using IF-statements).