Design Method of Multi-Micro-Computer Redundancy System Based on CAN Bus

Redundancy technology is an important measure to enhance the reliability of computer control system. The characters of traditional redundancy and CAN bus are analyzed. The design and implementing method of Multi-Micro-Computer is presented. In the system, none of the nodes is assigned as master changelessly. The node, which acts as master, is determined through competition after the system is powered up. This way ensures that the system can be working order even if only one node is in normal. The logical structure of the system is presented too. The switch protocol between master computer and backup computer and the method of competing for master among all the nodes are described in detail. The system can achieve that backup computer switches to master computer without disturbance. Because the method of software and field bus combination is adopted to replace traditional hardware switch circuit in the system, the reliability of the whole system is enhanced. The novel redundancy system is of low-cost, openness and good maintainability.