A cable detection apparatus includes; a plurality of conductors which transmit signal information, a detection control circuit operably connected to a first conductor of the plurality of conductors, wherein the detection control circuit outputs an output signal as a first detection signal when a predetermined signal level is detected from the first conductor and outputs a second detection signal when the predetermined signal level is not detected from the first conductor, and a multiplexer operably connected to the detection control circuit which receives one of the first and second detection signals and selects between a digital signal input and an analog signal input based on the output signal of the detection control circuit and outputs the selected signal input to a conductor of the plurality of conductors.