数字秒表的设计，设计并调试一个计时范围为0.01秒~1小时的数字秒表，并用实验开发系统进行硬件验证。有详细步骤和源码。-The digital stopwatch s design, designs and debugs a time scope is 0.01 second ~1 hour digital stopwatch, and carries on the hardware confirmation with the experiment development system. Has the detailed step and the sound code.