秒表计数，在c51单片机上用键盘控制，启停秒表，用于数码管显示-Stopwatch counting, in the C51 single-chip using the keyboard control, start and stop the stopwatch used in digital display

51 单片机 由温度传感器采集温度数据。由数码管显示。-51 single-chip temperature data collected by temperature sensors. By the digital display.