NoiseGen.scl

Name: FB1863
Symbolic Name: NoiseGen
Symbol Comment: Noise Generator
Family: Genrator
Version: 5.0
Author: AdvLib80
Last modified: 04/13/2011 Size: 358 byte


FUNCTION_BLOCK FB11863 // FB1863
TITLE ='Noise Generator'
AUTHOR : AdvLib80
FAMILY : Genrator
NAME : NoiseGen
VERSION : '2.0'
 
VAR_INPUT
  StdDev                        : REAL  := 1.000000e+000;   //standard deviation of the noise signal (variance=StdDev^2)
  Offset { S7_edit := 'para' }  : REAL := 2.000000e+001;   //meanvalue of the noise signal
  Enable                        : BOOL  := TRUE;            //noise-enabling
  Restart                       : BOOL  := TRUE;            //complete restart
END_VAR
VAR_OUTPUT
  Noise                         : STRUCT                    //output noise sample
   Value                        : REAL ;                    // Value
   ST                           : BYTE  := B#16#80;         // Signal Status
  END_STRUCT;   
END_VAR
VAR
  xn                            : DINT ;   
  m                             : DINT ;                    //parameter
  d                             : REAL ;   
  _reserve                      : ARRAY  [0 .. 7 ] OF BYTE  := B#16#0;   
END_VAR
VAR_TEMP
  xnp1                          : DINT ;   
  produkt                       : DINT ;   
  ynp1                          : REAL ;   
  i                             : INT ;   
END_VAR
BEGIN
 
IF Restart
THEN
    xn:= 11;
    Restart:=false;
    Noise.Value:=0.000000e+000;
    m:=59049;
    d:=DINT_TO_REAL(m/9);
ELSE
    IF Enable
    THEN
        produkt:=5*xn+1;
        xnp1:=produkt MOD m;
       
        FOR i:= 1 TO 9 BY 1 DO
           
            IF INT_TO_REAL(i-1)*d <= DINT_TO_REAL(xnp1)  AND  INT_TO_REAL(i)*d -1.0 >= DINT_TO_REAL(xnp1)
            THEN
                ynp1:=INT_TO_REAL(i);
            END_IF;
      
        END_FOR;
   
       ynp1:=(ynp1-5.130000e+000) / 2.592716e+000 - 6.595402e-003;    
       Noise.Value:=ynp1 * StdDev + Offset;
       xn:=xnp1;  
    ELSE
        Noise.Value:=0.000000e+000;   
    END_IF;;
END_IF;
 
END_FUNCTION_BLOCK