AT24C02，利用定时器产生一个0~100秒变化的秒表，并且显示在数码管上，每过一秒将这个变化的数写入EEPROM内部。断电后再次接通电源，单片机先从EEPROM中将原l来写入的数据读出，接着此数继续变化并显示在数码管上 。P1口接数码管为选，直接由单片机I/O口控制；P0口接573，控制段选。-AT24C02, the use of timers to generate a change from 0 to 100 seconds stopwatch, and displayed on the LED on, every one second to write this number changes the internal EEPROM. Turn the power off again, single-chip EEPROM of the original l start to write the data read-out, then this number continues to change and display the digital pipe. P1 port access control for the selection of digital, direct from the single-chip I/O port control　P0 port 573 connected to control the segment selector.