The Software Development Of PCB Test System Based On Boundary-scan Technology

In order to promote the application of boundary-scan (BS) technology in electronic equipments, research was focused on the boundary-scan test for PCB and then a PC-based test system developed, which realizes data communication and fault diagnosis through software. The software system is built up by VC++ language and has the following main characteristic: supporting BSDL, automatic creation of test vectors, complete test of BS chain faults, realization of PCB faults diagnosis, feasibility to test of inner function of chip, especially automatic creation of SVF file for all tests.In this file, at first the history of BS technology was reviewed and BS standard and some basic test theories were briefly induced.Thereafter the software test system was fully described by account for structure of hardware interface circuit and explanation of class structure of software module corresponding to functions.In faults test of PCB, bus diagnosis is the first step. As there isn't any good method to solve bus diagnosis through previous research, a new test method was designed. Using this method, bus faults can be diagnosed correctly under primary and down test. Secondly, one improved algorithm that is self-adapted, has less PTVs and fits multi-node connect diagnosis was put forward and applied to diagnose the stuck faults and connect fault. Thirdly, on basis of test secquence and boundary-scan structure, inner logic of chip was sucessfully tested.At the end of this file, problems in extending test software system were raised for subsequent research.