Structured text¶

IF Start AND NOT Stop THEN
    Motor := TRUE;
ELSIF Stop THEN
    Motor := FALSE;
END_IF;

Delay.TON(IN := Motor, PT := T#5s);
Lamp := Delay.DN;

• Statements: :=, IF/ELSIF/ELSE, CASE, FOR, WHILE, REPEAT, EXIT, RETURN.
• Operators: + - * / MOD **, AND OR XOR NOT, = <> < <= > >=.
• Literals: TRUE, 16#FF, 2#1010, T#1m30s, 3.5.
• Timers, counters and PID are called on their tag: Delay.TON(…), Parts.CTU(CU := Sensor, PV := 10), Loop.PID(PV := Level, SP := 50.0, CV => Valve).
• Routines and blocks: JSR(Fill);, "Scale"(In := Raw, Out => Level);, "Motor1"(Run := Start);.
• Arrays and members: Recipe[Step].FillTime.

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See the function reference.