现场总线MAC层的分析  

The Analysis of the MAC Layer of Fieldbus

作　　者：徐应跃[1] 吴爱国[1] 

机构地区：[1]天津大学电气自动化及能源工程学院,天津300072

出　　处：《化工自动化及仪表》2001年第2期4-7,共4页Control and Instruments in Chemical Industry

摘　　要：现场总线的MAC层在很大程度上决定了网络的实时性与可靠性 ,可以说是现场总线系统的关键。介绍了MAC层的两大体系 :令牌环 /令牌总线和CSMA/CD ,并深入分析了它们各自的代表 :PROFIBUS和LON WORKS的MAC层的实现方式 。The MAC layer largely determines the real time behavior and reliability of a fielbdus,so it is said to be the key to the fieldbus.The paper discusses two main systems of MAC layer:token ring/token bus and CSMA/CD.Moreover,we analyze the methods of realizing MAC layer,which are used by PROFIBUS and LONWORKS,representatives of the two systems.And their advantages and disadvantages and also discussed.

关 键 词：工业控制 现场总线 MAC层 令牌环 令牌总线 CSMA/CD 

分 类 号：TP273.5[自动化与计算机技术—检测技术与自动化装置]