CAN总线实时性研究及改进

随着CAN总线控制网络的复杂化，单段网络上的控制节点数目增多而且网络带宽利用率要求日益提高，这使得总线上属性优先级低的数据传输延时增加；提出了一种动态时分CAN的设计思想，理论上给出了不同属性数据帧传输的最大时延；解决CAN现场总线在网络带宽利用率高时，数据传输的实时性问题，尤其是保证了低优先级信息的实时性；而且，相对于TF—CAN具有更好的灵活性；实验结果证嘲；同属性的数据时延都得到了减少，尤其是属性优先级低的数据；验证了设计思想，证明了协议的可行性。

Analysis and Improvement of Realtime in CAN Bus

With the more complexity of CAN-NCS, the number of control nodes in single bus became increased and the utility of the bandwidth are required improvement, this made more delay of the PRI information. A new design mode based on dynamic time division multiplexing was introduced, and in theory the maximal delay of various data frame was deduced. The real-time problem of the data transfer was solved and especially for the lower PRI information when the utility of controller area network (CAN) fieldbus was high. Furthermore, compared with the TT-CAN, it is more flexibility. The result of the experiment validate that the delay of all the data frame are decreased, especially for the lower PRI information. This indicates that the design mode was correct and the protocol was feasible.