一个简单的电子跑表， 使用单片机中的定时计数器；上电或复位键后显示000.0 当按下启动键时，作为跑表使用，显示范围是: 000.0-999.9秒， 当按下停止键时，跑表停止运行，并保留所停位置的时间显示不变。当按下清零重计数键时，马上跳回000.0 重新开始计数。-A simple electronic stopwatch, timer counter using microcontroller　After power-up or reset button displays 000.0　when pressing the start button, a stopwatch use, display range: 000.0-999.9 seconds, press the stop button when , stopwatch stops running, and keep the stop position of the time display does not change. When you press the clear key to re-count, immediately jump back to 000.0 starts counting again.