早期基于AT89S52独立编写的基本测试程序，带DS18B20(带CRC效验)、LCD1602、AT24C02、DS1302，代码简洁，供初学者参考学习。-AT89S52 based on an independent preparation of the early basic test program, with DS18B20 (with CRC-tested), LCD1602, AT24C02, DS1302, code simplicity, reference for beginn