在CAN总线中,位定时有一点小错误就会导致总线性能严重下降。虽然在许多情况下，位同步会修补由于位定时设置不当而产生的错误，但不能完全避免出错情况，并且在遇到两个或多个CAN节点同时发送的情况时，错误的采样点会使节点启动错误认可标志，使节点不能赢得总线上的任何活动。因此要分析、解决这样的错误就需要对CAN总线位定时中的位同步和CAN节点的工作过程有一个深入的了解。本文描述了CAN总线位同步的运行规则以及如何对位定时的参数进行设置。-In the CAN bus, there is a little bit timing errors will lead to a serious decline in bus performance. Although in many cases, bit synchronization bit timer settings will fix improper because of errors, but can not completely avoid error conditions, and in the event of two or more CAN nodes simultaneously send the case, the error of the sampling points will node startup error recognition signs, so that nodes can not win any activity on the bus. Therefore, to analyze and solve this error you need for the CAN bus bit timing and bit synchronization in CAN nodes have a working understanding of the process. This paper describes the operation of the CAN bus bit synchronization bit timing rules and how to set the parameters.