Abstract: The paper introduces the software design of the onboard image data processor based on CAN bus.The processor uses AT80C32E as CPU and SJA1000 as CAN bus controller to realize its communication object.It summarizes the character of AT80C32E and SJA1000 from the system structure of the processor hardware.，then introduces the details of the software design process，including the initialization of SJA1000，message transmitting and receiving and the main work flow of the software design.Finally this paper discusses several questions occurred in the design process.

Key words: Controller Area Network（CAN） bus, single-chip microcontroller, SJA1000

摘要： 介绍了一款采用单片机和CAN通信控制器SJA1000实现CAN总线通讯的星载图像数据处理器的嵌入式软件的设计方法，从设备系统拓扑结构出发，介绍了单片机和SJA1000的特点，详细介绍了软件设计流程，包括CAN控制器初始化、收发数据、主程序流程图，并详细讨论了设计中几个应该注意的问题。

关键词: CAN总线, 单片机, SJA1000