CAN总线在测绘相机控制器中的应用设计

为了实现测绘相机控制器与星务计算机之间的可靠数据通讯,对CAN总线在测绘相机控制器中的应用方法进行研究。首先,根据CAN总线工作原理对硬件电路进行设计,然后在对CAN总线控制器和TSC695的接口逻辑进行分析比较的基础上,采用状态机设计法解决接口时序的不匹配性问题,并利用Modelsim软件对状态机进行时序仿真与验证。最后介绍了CAN总线控制器初始化配置流程和定时状态设计方法。实验结果表明:相机控制器通过CAN总线以307.2 kb/s波特率通讯时无错误,CAN总线接口状态机的时序余量能够达到20%,满足测绘相机控制器CAN总线通讯的可靠性要求。

Design of Applying CAN Bus in Mapping Camera Controller

In order to realize reliable data communication between control unit of mapping camera and house-keeping computer，a method of applying CAN bus to control unit of mapping camera was developed.First，the hardware circuit was designed based on the principle of CAN bus.Then，on the basis of analysis to the interface logic of both CAN bus controller and TSC695，a state machine design was proposed and realized for solving the unmatched timing problem.Timing simulation and verification were made for the state machine using Modelsim software.The initialization procedure of CAN bus controller and CAN bus timing status were also discussed.Experimental results indicate that:1) all data communication is right when communication baud rate of CAN bus of mapping camera controller is 307.2 kb/s;and 2) timing margin of the state machine of CAN bus interface can reach 20%.Therefore，it can meet the requirements of reliability of CAN bus communication.