Design Of Embedded Data Acquisition System With High Precision Based On ARM9200

The process that convert analog signal into digital signal,and storge, display is called Data Acquisition,and the correspond system is called Data Acquisition System. Data Acquisition is the basic means that can obtain various information. Data Acquisition is an important branch of the information science. It is a technique of synthetical application, which is based on the technology of the sensor, the technology of signal measurement and processing ,computer science, and so on.This paper designed and realized a Data Acquisition System with high precision for the intensity of magnetic field based on AT91RM9200 and embedded Linux. Firstly, the conception, significance and state of arts of data acquisition was introduced in detail with the characteristic and application of ARM architecture, the definition, history and development of embedded systems, new technologies and challenge in embedded systems design, the characteristic of embedded Linux, the research and development of embedded microprocessor and embedded software. Secondly, the hardware architecture of DAS and choice of components was briefly introduced. Thirdly, the use of development tools in Linux was introduced detailedly and the Linux device drivers was illustrated. The realization of the driver of ADS1256 was also presented. Lastly, the design of applications in ARM and Linux was presented.In our design AT91RM9200 was used as the system's processor. ARM9TDMI is a RISC processor with high effectiveness and low power waste. AT91RM9200 adopts ARM9TDMI as its kernel and is a 16/32—bit micro controller for eternet application with high-performance,cost-effective. Therefore, AT91RM9200 is especially fit for embedded products. The ADS1256 of TI Corp was used as AD convertion chip. ADS1256 is an AD converter for industry application with the excellent performance of low noises and high speed. The operation system used embedded Linux. There are abundant resources for Linux, and Linux is welcomed by developers for its open source code.