Method of stopping data communication of a communication apparatus based on a detection of a power supply voltage drop

摘要

In data communication apparatus for communicating with another data communication apparatus via cables, when a power supply voltage applied to the data communication apparatus drops and the application of the power supply voltage is stopped, a power-supply-voltage-drop detecting circuit immediately detects the drop in the power supply voltage, thereby detecting the stop of application of the power supply voltage. When the stop of the power supply is detected, a stop signal outputting circuit outputs a communication stop signal to said another data communication apparatus. Accordingly, when power supply is stopped in one of the two pieces of data communication apparatus, it is possible to prevent a malfunction from occurring in the other data communication apparatus.