Attention

IronPLC can only run very simple programs. The steps described are accurate but many language features are not yet supported.

REPEAT

The REPEAT statement executes a statement list and then evaluates a boolean condition to determine whether to repeat.

IEC 61131-3	Section 3.3.2.4
Support	Supported

Syntax

REPEAT
    statement_list
UNTIL expression
END_REPEAT ;

Description

The REPEAT loop executes the statement list at least once. After each iteration, the boolean expression is evaluated. If the expression is TRUE, the loop terminates. If it is FALSE, the statement list executes again.

This is the opposite of a WHILE loop: WHILE continues while the condition is true, whereas REPEAT continues until the condition becomes true.

Example

PROGRAM main
    VAR
        count : INT := 0;
    END_VAR

    REPEAT
        count := count + 1;
    UNTIL count >= 10
    END_REPEAT;
END_PROGRAM

See Also

• WHILE — pre-tested loop

• FOR — counted loop

• EXIT — break from innermost loop