Usb Bus-based Physiological Signal Acquisition System Developed

The paper is mainly focused on the design process of bioelectric signal acquisition system that is based on USB bus. The design scheme, developing method and developing process of a suit of data acquisition used with Nanjing QingHeng Electronics Co.Ltd's USB interface chip CH372 and ATMEL's AT89C52 are expatiated. In addition, the material realization is given in the paper.At first, the protocol of USB bus is introduced in brief , then the data acquisition system is discussed , which include four segments design, hardware design,firmware design, device driver and application program .In hardware segment, the performance of CH372 is firstly described, the scheme are given in detail. At last some questions in design which should be considered in design are analysed.Firmware writing is the most important project in the paper. The idea of program design and the frame are firstly showed. The program design is introduced step by step. Finaly, some codes are given to realize the program design.In driver and application program segment, the principle of choosing driver program and developing tools are presented. Moreover the structure and writing steps of device driver are discussed. The design of host application program is simple, which provided a friendly user interface to control the acquisition system and display the data. So there is not much content in paper.The paper has finished the design of bioelectric signal acquisition system based on USB interface and realized the basic data acquisition function.