Logic Analyzer Design Base On USB

Logic analyzer is one of the most important data domain test instruments. With the accelerating advancement of calculation and electricity, logical analyzer is getting widely used. As its functions and capabilities raised, there are more demands for operational convenience and easy portability. Then USB technology is a new technology in the last years. It has much virtue such as fast transmission speed,plug and play,taking convenience,good currency capability ,and so on. So USB technology has widely using development foreground USB technology will be used in the design of Logic analyzer in the future. Portable logic analyzer based on USB is light and handy, which is easy to carry and operate. With utilization of computer, the logic analyzer based on USB enhances data transmission, process, display and storage, which improves the performance of data analyzing, and in another aspect, it can also greatly lower the cost of the instrument And build the flat roof for virtual instrument test system.This paper expatiates the principle of the software and hardware design of a logic analyzer based on USB and brings forward a scheme. The principle and design of the data acquisition section and the USB interface section are emphasized in this paper according to the difficulties of the hardware design. The software, which is closely related with the hardware, is also mentioned in the paper.The first chapter describes the actuality of USB technology and logic analyzer's development tends in the field of electricity. The work and the specified specs of this instrument are also introduced in this chapter. Chapter 2 specifies USB protocol and the design scheme of USB interface board.The principle and design of the circuits in data acquisition section are expatiated in chapter 3, which introduces the designs of the trigger word distinguished circuit and the storing control circuit in detail. And brings forward a scheme of two MCU communication. A design of increasing storing capability is also introduced in this chapter. Chapter 4 describes the design of user application interface, the method and debugging base on LabView.The question and solution in design process are dissertated in chapter 5. Chapter 6 summarize the whole design and debugging.Testing shows that the logic analyzer has basic manage ability, as well as rapid data transfer speed of USB interface, can take more exploitation and research, and has widely application foreground.