摘  要：以太网用于数控系统首先要解决的就是实时性问题，而实时性问题主要来源于冲突检测载波监听多点访问（CSMA/CD）机制。该文提出了一种基于集总帧，应用于环型拓扑结构的确定性通信系统。该系统实现了各节点的顺序、分时收发数据，有效地避免了通信过程中的冲突，减小了通信延时。经过实验验证，证明了设计的可行性和有效性，能够满足数控系统中确定性通信的要求。
关键词：数控系统;以太网;集总帧;环形拓扑

Abstract: The primary problem of using Ethernet into CNC system is the real-time problem which mainly caused by carrier sense multiple access with collision detection (CSMA / CD) mechanism. This paper proposed a communication system which maked it possible to send and receive data orderly by combining summation frame with ring topology. This communication system effectively avoided conflict and reduced the time delay in the process of communication. Experiment result proved the feasibility and validity of the designed system.
Key Words: CNC system; Ethernet; Summation frame; Ring topology