使用NE555芯片把热敏电阻的电阻值转化为相对应的频率值，然后由AVR单片机接受频率值后，由led数码管显示出来。数字温度计。-Using NE555 chips to the thermistor resistance values are converted to the corresponding frequency value, and then accepted by the AVR microcontroller frequency value, the digital control displayed by the led. Digital thermometer.