利用单片机AT89C51控制DS18B20温度传感器对水温控制，当水温低于预设温度值时系统开始加热, 红色发光二极管点亮表示进入热状态，当温度达到预设温度值时自动停止加热,红色发光二极管自动熄灭。预设温度值和实测温度值分别由两个3位数码管显示，范围为0～99℃-Control using SCM AT89C51 DS18B20 temperature sensor temperature control, when the water temperature is lower than the preset temperature value system begins to heat, the red LED lights to indicate the state into the heat when the temperature reaches the preset temperature automatically stop heating, automatic red light-emitting diode extinguished. Preset temperature value and the measured temperature value by two three digital display, the range of 0 ~ 99 ℃