Development Of Serial Bus Protocol Analysis Software Package Of Oscilloscope

As an intelligent measurement instrument, Oscilloscope has many kinds of functions, such as measurement, display, analysis, record and so on. It has a wide range of applications. Since the serial bus has advantages of low cost, long transmission distance and simple interfaces, more and more components are connected by serial bus, the demand of oscilloscope with the function of serial bus protocol analysis is growing. To solve this problem, this thesis developes serial bus protocol analysis software package of oscilloscope, it applies to the 20GSa/s bandwidth high-speed multi-functions oscilloscope developed by major instrument special project in Ministry of Science, which is used as oscilloscope application software package to analyze eight kinds of serial bus protocol(CAN, FlexRay, ARINC429, MIL-STD-1553 B, I2 C, SPI, UART and USB). The development of this software package has important value.The thesis ascertains the function, input and output of each module and divides the software packet into 8 modules according to their functions, each of which implements the utility of protocol analysis for one bus type. Before designing the software packet, some key techniques need to be researched, such as filtering which is used to reduce the glitch and noise effect on decoding algorithm, digital data forming which to improve the speed and efficiency of decoding, determining the electrical level of every bit which to guarantee the accuracy of protocol analysis and designing corresponding algorithm for each key technique. With the support of these techniques mentioned above, the thesis studies the module design method with commonality: programming codes with specialized function(filtering function, digital data forming function, serial bus decoding function, etc). In this way, modules can be implemented, and they can also process and compute the bus data acquired by the oscilloscope in order to get some important information and identify the errors during bus communication.Finally, two testing plans are designed: one can verify the function on real oscilloscope called field test and the other must allow related test without the platform of an oscilloscope called equivalent test. All of the modules have passed the equivalent test and four of them have accomplished the field test. The result shows that the software packet is able to interpret the data sampled by the oscilloscope to bus content text according to the corresponding bus protocol format and recognize the errors on bus during communication, which fulfills the requirement.