1 FUNCTION_BLOCK TRANSFER

     2  VAR_INPUT

     3    AUTO : BOOL ;     (* 1 - track X0, 0 - ramp or hold *)

     4    XIN : REAL ;      (* Typically from PID Function Block *)

     5    FAST_RATE, SLOW_RATE : REAL ; (* Up/down ramp slopes *)

     6    FAST_UP, SLOW_UP, (* Typically pushbuttons *)

     7    FAST_DOWN, SLOW_DOWN : BOOL;

     8    CYCLE : TIME ;    (* Sampling period *)

     9  END_VAR

    10  VAR_OUTPUT XOUT : REAL ; END_VAR

    11  VAR XFER_RAMP : INTEGRAL ;

    12      RAMP_RATE : REAL ;

    13  END_VAR

    14  RAMP_RATE := 0.0 ;

    15  IF NOT AUTO THEN

    16   IF FAST_UP THEN RAMP_RATE := FAST_RATE; END_IF;

    17   IF SLOW_UP THEN RAMP_RATE := RAMP_RATE + SLOW_RATE; END_IF;

    18   IF FAST_DOWN THEN RAMP_RATE := RAMP_RATE - FAST_RATE; END_IF;

    19   IF SLOW_DOWN THEN RAMP_RATE := RAMP_RATE - SLOW_RATE; END_IF;

    20  END_IF ;

    21  XFER_RAMP (RUN := 1, CYCLE := CYCLE, R1 := AUTO,

    22             XIN := RAMP_RATE, X0 := XIN) ;

    23  XOUT := XFER_RAMP.XOUT;

    24 END_FUNCTION_BLOCK

    25