Electronic device capable of counting down to an integral time point

摘要

An electronic device capable of counting down to an integral time point has an integral time point selector for setting an integral time point. A timer serves for recording the current time. A synchronous calculating unit serves for reading the integral time point from the integral time point selector and reading the current time from the timer. The time interval from the current time to the integral time point is calculated as a counting down time period. A counter serves for reading the counting down time interval from the synchronous calculating unit and starting to count down.