code-scl.scl

(*
    Edge evaluation in SCL BY Jorge
    Based on "Wie können Sie in STEP 7 (TIA Portal) mit SCL eine Flankenauswertung realisieren?" BY Siemens

    Primary variable   = PB
    Auxiliary variable = Aux_PB
    Rising edge        = Pos_PB
    Falling edge       = Neg_PB
*)

#Aux_PB := #PB;

// Rising edge
#Pos_PB := #PB AND NOT #Aux_PB;

// Falling edge
#Neg_PB := NOT #PB AND #Aux_PB;