Introduction - If you have any usage issues, please Google them yourself
The design of the stopwatch
With 89 c51, external crystals, reset circuit, two digital tube, two buttons, do an electronic stopwatch, specific requirements for the stop watch with buttons, design the countdown time available buttons (such as 10 s and 20 s, 60 s), and start the countdown function. One of the above two functions can be selected by key.
Packet : 39709579danpianjimiaobiao.rar filelist
danpianjimiaobiao.doc