diff -r 000000000000 -r fb772792efd1 AnnexF/derivative_st.txt --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/AnnexF/derivative_st.txt Wed Jan 31 15:32:38 2007 +0100 @@ -0,0 +1,18 @@ + FUNCTION_BLOCK DERIVATIVE + VAR_INPUT + RUN : BOOL ; (* 0 = reset *) + XIN : REAL ; (* Input to be differentiated *) + CYCLE : TIME ; (* Sampling period *) + END_VAR + VAR_OUTPUT + XOUT : REAL ; (* Differentiated output *) + END_VAR + VAR X1, X2, X3 : REAL ; END_VAR + IF RUN THEN + XOUT := (3.0 * (XIN - X3) + X1 - X2) + / (10.0 * TIME_TO_REAL(CYCLE)) ; + X3 := X2 ; X2 := X1 ; X1 := XIN ; + ELSE XOUT := 0.0; X1 := XIN ; X2 := XIN ; X3 := XIN ; + END_IF ; + END_FUNCTION_BLOCK +