Serial Bus Protocol Analysis Trigger Function Module Design

Mixed-signal digital oscilloscope (MSO) which based on the improvements of digital storage oscilloscope, is developed after the emergence of the logic analyzer, and has been the new generation measuring instruments. Digital storage oscilloscopes and logic analyzers these two essential measurements in the field of electronic measuring instruments, with a variety of signals circuit debugging process efficiency often can not advance to a satisfactory level, so in the field of electronic measuring separately using a logic analyzer or digital storage oscilloscope are not on the characteristics of the signals in time domain and data domain and its relevance for in-depth analysis of expression. Therefore, the time-domain analysis of the data domain analysis capabilities that both the logic analyzer and digital storage oscilloscope mixed-signal digital oscilloscope quietly come out, and will certainly become an essential of modern test equipment.This article focused on the single function of the domestic digital storage oscilloscope defects, design a USB serial bus protocol analysis function module based on XILINX FPGA. Focusing on how to achieve accurate data acquisition as well as conditions for the serial bus trigger, accurate analysis on the serial bus data transfer mode, and the analysis of the physical layer and protocol layer, and explore.Another key point of this work is the FPGA implementation of real-time monitoring and protocols trigger for data transmission on the serial bus. Not interfere with equipment on the bus is in working condition, so how bus data capture and analysis has become particularly important. This design do a detailed analysis and validation on the USB bus protocol in-depth understanding of the design module is divided into sub-module workflow schematic circuit design, PCB layout and circuit debugging.