Mitsubishi Electric MELSEC L series, Руководство по программированию

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3 HANDLING OF CHARACTERS AND NUMERIC VALUES IN ST PROGRAMS
3.3.2 Labels
In ST programs, labels can be used with data.
When labels are used in an ST program, label declaration must be made on the local
variable setting screen or global variable setting screen before use.
(For the label and structure label declaration methods, refer to the "GX Developer
Operating Manual".)
Label representation examples in ST programs are as follows.
Example: Switch_A:= FALSE; (* FALSE is assigned to Switch_A. *)
Example: IF INT_TO_BOOL(Unit_No) = FALSE THEN
Line_No := 2147483647;
END_IF;
(* IF INT_TO_BOOL (Unit_No) is FALSE *)
(* 2147483647 is assigned to Unit_Number. *)
Example: Limit_A := E1.0; (* 1.0 is assigned to Limit_A *)
Example: Conveyor[4] := Unit_No;
(* The value of Unit_No is assigned to *)
(* the fifth element of Conveyor. *)
Example: stPressure.Status := TRUE; (* TRUE is assigned to *)
(* element name Status of stPressure. *)
Example: stPressure.eLimit := E1.0; (* 1.0 is assigned to *)
(* element name eLimit of stPressure. *)