The Software Design Of In Circuit Test System Based On The FPGA

In-circuit testing of the printed circuit board,as an important part in the generation process of the circuit board,concerns the quality of the whole electronic product.This paper makes an intensive study of the current situation of in-circuit test system at home and abroad,and analyzes advantages and disadvantages of in-circuit test equipment at home and abroad.Then,the work principle of in-circuit test equipment and the test principle of the components which are widely used in the market are studied and learned.So a FPGA-based in-circuit test system is designed and developed.This thesis mainly introduces four aspects.The first one is the work principle of the in-circuit test system,the test principle of the components and hardware design proposal of the system.PC and the architecture of duel-level FPGA are used as hardware,which make the test system have a stronger competitiveness in the market by utilizing the features that PC is light and flexible,and FPGA is fast,low power consumption and a strong universality etc.The second one is the software design of in-circuit test system and the research of its optimization algorithm.Based on LabVIEW2011 as the development platform,the system designs PC software in detail,and is specific to each function module including the realization of permission setting function module,autonomic learning function module,self-diagnostic function module,component test function module and auxiliary test function module.Meanwhile,this system applies Kautz algorithm to open short circuit study and test in order to make their speed get a great improvement.The third one is the design of USB interface module.The system realizes the data exchange between the host computer and the lower computer by adopting the USB communication mode,and the hardware chooses the micro-controller CY7C68013A which is the high integration and low power consumption USB2.0 from Cypress Company,in view of USB communication module to write the firmware program,driver and.inf file of the chip CY7C68013A and design the frame format of the host computer and the lower computer communication.The fourth one is the design of the lower computer software.The lower computer mainly consists of four parts:master control board,switch board,AC board and DC board,and each part has a piece of Altera FPGA which can completes the work of the controller by using hardware description language Verilog HDL for its programming as controler.Due to frequent data exchange of the master control board,FPGA on master control board designs SOPC to realize the software design of master control board with the Verilog HDL and embedded C language.This system has done with PCB test quickly,so it fully complies with the requirements of the project.