Research On Self-diagnosis And Self-repair Technology For Digital Reconfigurable Hardware

With the rapid development of integrated circuit manufacturing process, the integration and complexity of digital electronic systems are increasing greatly, and the probability of failure in the life cycle is becoming larger and larger. At present, highly integrated digital electronic systems are widely used in various fields, especially in the critical systems where artificial maintenance are difficult to implement because of harsh environment, so the reliability of digital electronic systems is highly demanded. Reconfigurable hardware provides more flexible design approaches for building highly reliable digital electronic systems, and self-diagnosis and self-repair technology in the field of highly reliable digital system design has great importance.The main work of this paper is to study the techniques of built-in self-diagnosis and self-repair for reconfigurable hardware.The main research work is as follows:(1) The self-diagnosis and self-repair of reconfigurable hardware interconnect resources need external control, can hardly be implemented online, and have large hardware overhead. For these problems, the paper provides a design scheme of circuit structure which can be self-diagnosis and self-repaired online. Based on the design of the circuit,the paper proposes the diagnosis method of interconnection resources,which includes two processes of the initial diagnosis and the precise positioning. The processes of initial diagnosis can judge interconnection failure. The processes of precise positioning can pinpoint the exact location of fault. We propose a self-repair method of interconnection resources, its main idea is to bypasses the fault multiplexer and shift fault lines. The experimentals demonstrate that the self-diagnosis and self-repair method can improve the interconnect resource fault-tolerance capability, and reduce resource overhead.(2) The online self-diagnosis and self-repair methods of configured logical block(CLB) are usually difficult to online implement, and the time and hardware resources overhead are usually very large. In this paper, the configurable logic blocks designed which has self-diagnostic capabilities. We propose the method of online cycle diagnosis, and improve the structure of two-module redundant circuit, which is able to implement self-repair through the reconfiguration of the configurable logic layer. This method make the circuit have self-repair capacity while it does not increase the hardware overhead. The experiments show that this self-diagnosis and self-repair method is easy to implement, and can greatly reduce the time and hardware overhead. (3) Based on practical circuits as an example, which realize functional mapping on the reconfigurable hardware, and apply modelsim software to realize layout and routing simulation. We develop the reconfigurable hardware validation experiment board; its FPGA chip adopts the XC2S200-5PQG208C. The design of the circuit is downloaded to experiment board to test, the experiments show the proposed methods is feasible and accurate.The research of this paper is funded by National Natural Science Foundation of China (60871009), Aeronautical Science Foundation of China (2009ZD52045) and Nanjing University of Aeronautics and Astronautics special research projects of basic research (NS2010086).