author | lbessard |
Wed, 14 Jan 2009 20:54:29 +0100 | |
changeset 166 | 09004f402097 |
parent 0 | fb772792efd1 |
permissions | -rwxr-xr-x |
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