Design Of CAN-USB Data Interaction System Base On FPGA

Computerized tomography,or CT,is one of the few medical diagnostic tools that can effectively detect diseases in the human body.In CT,FPGA is usually selected as the controller of the electronic system in order to make each functional unit work together due to the complexity of its internal work and the requirement of absolute security and stability.CAN bus has become the communication bus used in CT because of its safety,stability and the ability to suppress electromagnetic interference.In the process of CT debugging,the parameters of each functional unit mounted on the CAN bus need to be adjusted frequently for practical needs.If the code that modifies configuration information of CAN bus node is adopted for each adjustment and then the FPGA is re-burned,the debugging efficiency is extremely low.Therefore,aiming at the actual needs of engineering,this paper designs a can-usb data interaction system based on FPGA,which CAN improve the debugging efficiency of CT by quickly and efficiently adjusting functional unit parameters.The main research work of this paper is as follows:First.CAN bus controller is designed based on FPGA.This paper refers to the previous analysis of the functions of CAN bus controller,adopts a new structure and design method,and makes a lot of improvements on it,and successfully realizes the new CAN bus controller on FPGA,which reduces the occupancy of FPGA resources and enhances the communication performance.Second.Firmware design and FPGA side control logic design are carried out based on the selected USB bus controller.In this paper,the USB controller CY7C68013 of Cypress company is selected in the USB design,and the USB controller is developed according to the actual engineering needs under the development framework provided by Cypress company,which basically meets the needs.The control logic of USB controller is designed in FPGA to realize data interaction between FPGA and CY7C68013.Third,CAN-USB data interaction system is designed based on hardware platform.This part includes FPGA core board and floor on the hardware.FPGA control logic includes CAN interaction unit design,USB interaction unit design,CAN-USB data interaction module design.The three parts contain and invoke each other to realize the data interaction of two different communication protocols.After testing on the hardware platform,the can-usb data interaction system designed in this paper has normal functions,stable data transmission and a success rate of 0.03% in the continuous transmission state,which meets the requirement of bit error rate of 0.05% in the CT debugging process.In addition,the design of the degree of integration and modularization is higher,the code logical structure is clear,strong portability,the interface of the constraint file can be slightly modified to other designs.