1  FUNCTION_BLOCK RAMP

     2    VAR_INPUT

     3      RUN : BOOL ;      (* 0 - track X0, 1 - ramp to/track X1 *)     

     4      X0,X1 : REAL ;

     5      TR : TIME ;       (* Ramp duration *)

     6      CYCLE : TIME ;    (* Sampling period *)

     7    END_VAR

     8    VAR_OUTPUT

     9      BUSY : BOOL ; (* BUSY = 1 during ramping period *)

    10      XOUT : REAL := 0.0 ;

    11    END_VAR

    12    VAR XI : REAL ;       (* Initial value *)

    13        T : TIME := T#0s; (* Elapsed time of ramp *)

    14    END_VAR

    15    BUSY := RUN ;

    16    IF RUN THEN

    17       IF T >= TR THEN BUSY := 0 ; XOUT := X1 ;

    18       ELSE XOUT := XI + (X1-XI) * TIME_TO_REAL(T)

    19                                 / TIME_TO_REAL(TR) ;

    20            T := T + CYCLE ;

    21       END_IF ;

    22    ELSE XOUT := X0 ; XI := X0 ; T := t#0s ;

    23    END_IF ;

    24  END_FUNCTION_BLOCK

    25