The 74F539 contains two independent decoders. Each accepts two address (A0 - A1) input signals and decodes them to select one of four mutually exclusive outputs. A Polarity control (P) input determines whether the outputs are active Low (P=H) or active High (P=L). An active-Low Enable (E) is available for data demultiplexing. Data is routed to the selected output in non-inverted or inverted form in the active-Low mode or inverted form in the active-High mode. A High signal on the Output Enable (OEn) input forces the 3-State outputs to the high impedance state.