基于ARM7 的汽车CAN 总线冗余网关设计

针对目前汽车内部连接ECU（Electronic Control Unit）的单线结构CAN(Controller Area Networks)总线网关, 一旦CAN总线线束损坏, 无法保证汽车各ECU之间稳定通信的问题, 提出了一种基于ARM7的冗余网关设计方案。该方案以ARM7处理器为中控网关控制器, 利用总线冗余的设计思想, 为主CAN总线备用辅助的CAN总线, 采用支持多任务实时调度的μC/OSⅡ作为实时操作系统, 在ADS（ARM -Developer- Suite）上软件编程完成各节点与网关之间的数据通信、 网关对数据中继转发、 总线故障切换。实验室组网测试表明, 该网关不但能与普通节点之间进行数据通信, 而且具有高低CAN总线节点之间的数据通信的中继转发功能, 在主CAN总线出现故障时及时切换到辅助CAN总线, 使整个车载CAN网络稳定可靠运行。

Design of Vehicle CAN Bus Redundancy Gateway Based on ARM7

In view of the single bus structure of present vehicle internal CAN(Controller Area Network) bus gateway can not guarantee the stability of communication between ECU(Electronic Control Unit) when meeting with wire damaged, this paper proposed a redundant gateway design scheme based on ARM7. The scheme used ARM7 processor as central gateway controller, utilized the ideas of bus redundancy design, spared an auxiliary CAN bus for the prime CAN bus, used μC/OSⅡ real-time operation system as software platform which supported multitasking real-time scheduling. Softwareprogramming on ADS completed the data communications between nodes and gateway,data relay of the gateway, switching the bus when the prime bus breakdown. Expe
rimental results showed that the gateway can complete not only data communication between nodes, but also relaying function between high CAN bus nodes and low CAN bus nodes, in addition, it can switch to the auxiliary CAN bus in time if theprime CAN bus met fault, all of this can make the whole vehicle CAN network stable and reliable.