etisserant@0:  FUNCTION_BLOCK AVERAGE
etisserant@0:    VAR_INPUT
etisserant@0:      RUN : BOOL ;      (* 1 = run, 0 = reset *)
etisserant@0:      XIN : REAL ;     (* Input variable *)
etisserant@0:      N   : INT ;      (* 0 <= N < 128 or manufacturer- *)
etisserant@0:    END_VAR            (*      specified maximum value  *)
etisserant@0:    VAR_OUTPUT XOUT : REAL ; END_VAR (* Averaged output *)
etisserant@0:    VAR SUM  : REAL := 0.0; (* Running sum *)
etisserant@0:        FIFO : DELAY ;      (* N-Element FIFO *)
etisserant@0:    END_VAR
etisserant@0:    SUM := SUM - FIFO.XOUT ;
etisserant@0:    FIFO (RUN := RUN , XIN := XIN, N := N) ;
etisserant@0:    SUM := SUM + FIFO.XOUT ;
etisserant@0:    IF RUN THEN XOUT := SUM/N ;
etisserant@0:    ELSE SUM := N*XIN ; XOUT := XIN ;
etisserant@0:    END_IF ;
etisserant@0:  END_FUNCTION_BLOCK
etisserant@0: