本设计是针对MCS—51型AT89C51系列单片机在采样、比较和控制方面的应用。本课题研究的主要内容是： 

（1）温度检测过程     

该环节使用铂电阻Pt100为测温元件，Pt100具有性能稳定、抗氧化性能强和测量精度高等优点，可以实现较为准确的测温。 

（2）数据的采集和转换过程 

数据采集系统是计算机对整个系统进行控制和数据处理，采用ADC0804实现由模拟量到数字量的转换。 

（3）温度控制过程 

采用中断的方式，当A/D转换结束，发出中断请求，单片机响应请求，驱动继电器动作，进行加热或冷却的处理。 

（4）显示过程 

        采用两位的LED数码管实现对现场温度的显示。-The design is applied for MCS-51 series MCU AT89C51-type sampling, compare and control. The main content of this research are: (1) the temperature detection process using the link Pt100 platinum resistance temperature measurement devices as, Pt100 with stable performance, strong antioxidant properties and high precision measurements, more accurate measurement can be achieved temperature. Acquisition and conversion process data acquisition system (2) of the data is a computer for control and data processing system, realized by using ADC0804 analog to digital conversion. (3) temperature control process using an interrupt, when the end of the A/D conversion, an interrupt request, the MCU responds to the request, the driver relay, heating or cooling process. (4) Display process uses two LED digital display temperature to achieve on-site.