Design of the CAN Bus Temperature & Humidity Data Acquisition System Based on C8051F040

In this paper, the DS18B20 is used as temperature sensor, the SHT71 is used as humidity senor, and the core of the intelligent CAN node consists of C8051F040. Using CAN bus system's characteristics and performance advantages and combining with the present situation of the large grain depot temperature and humidity measuring system, the paper gives the overall design of temperature & humidity measurement system and the program block diagram. The system is stable and reliable in the grain depot temperature measuring applications and has good expansibility. In the process of measurement, the system temperature and humidity data acquisition is accuracy, and error also is small, greatly. The automation degree of the temperature monitoring in grain depot has been greatly improved.