Research And Design Of Data Acquisition System Based On Msp430

The data acquisition system is a very important part in the digital signal processing and industrial automation. Base on the mass literature materials and onsale products. This paper designs a data acquisition system based on MSP430F5438which is mainly used for collecting the temperature and pressure values. The system mainly consists of two parts, hardware and software design.MSP430F5438microprocessor is the core in hardware designing. The signal acquisition part contains the collection of the temperature and pressure values. Temperature sensor DS18B20collects the temperature, while the manual input and program-controlled variable gain amplifier amplifies the output voltage signal of the pressure sensor in order to improve the accuracy of signal sampling. After that the LCD screen with touch displays the data and system operating parameters. And the data is stored in SD card in the form of FAT16. The system time is supplied by the external time module. In order to centralized monitor the data acquisition system in different places, a communication system based on RS485interface is designed. Since the static power consumption of the system is too large to design the two-wire transmitter output, the paper designs a three-wire transmitter output based on discrete components. In order to ensure the system stability and reduce the energy consumption, a solarrechargeable battery circuit is designed. In the last the paper puts forward the hardware anti-jamming measures.The software design contains two parts. First is to design the program for each module with C language in Integrated debugging environment Embedded Workbench. These modules include collecting the tempreture and pressure, changing the program-controlled digital potentiometer resistance, displaying thedata, the communication between different devices, writing digital to analog conversion module. The system uses timer interrupt, during the interrupt the system collects pressure data, and storage the data. Second is to use VC++6.0to design the PC program, which is mainly used for Modbus communication and real-time clock calibration.Additionally, This paper also does some research on the system’s low-power. The paper analysis the significance of the low-power design and describes the algorithm detaily. The algorithm contains software filter design, using the Least squares method to celibrate zero and full scare,"three-point method "touch screen calibration.In the last the design tests the functionality of each module of the sy--stem. And verify the rationality of the system parameters.