ELECTRONIC APPARATUS AND CABLE DEVICE

摘要

[PROBLEMS TO BE SOLVED] It is judged whether a connected cable is in conformity to a conventional specification or a new one. [MEANS FOR SOLVING THE PROBLEMS] An HPD signal line (902) has a pull-up resistor (911) connected with a voltage source in a circuit on a side of an expanding HDMI synch device (402) and a pull-down resistor (913) connected with the ground potential, and a reserve line (903) has a pull-down resistor (914) connected with the ground potential in a circuit on a side of the expanding HDMI synch (402) and a pull-up resistor (912) connected with a voltage source of an expanding HDMI source device (401) in a new HDMI cable (901). The expanding HDMI synch device compares a voltage at a test point (19) on the reserve line (903) on the side of the expanding HDMI synch device (402) with a reference voltage at a voltage comparator (916). A CPU of the expanding HDMI synch device (402) judges such a normal state that the new HDMI cable (901) is inserted in the case where an output from the voltage comparator (916) is high and also judges such a state that a conventional HDMI cable (931) is mistakenly inserted in the case where an output from the voltage comparator (916) is low.