本系统以AT89S52为核心，选用符合测量温度范围要求的DS18B20单总线数字温度传感器，DS1302串行时钟芯片，RT1602液晶显示器实现液晶显示当前日期、时间、星期和温度。当测量温度超过设定的温度上下限时，启动蜂鸣器和指示灯报警。温度显示稳定，温度值小数部分保留两位有效数字。-AT89S52 in the system as the core, consistent with the measured temperature range chosen required DS18B20 s

at89s52等单片机 的并口烧写器-at89s52 programing

This Project is used to control the Fan speed according to the temperature and it also indicates the temperature. The system will get the temperature from the IC (DS1820) and it will control the speed according the values stored in the code. The S

21位数码管显示万年历at89s52+ds1302+ds18b20-21 LED display calendar at89s52+ ds1302+ ds18b20