０　前言随着过程控制技术、自动化仪表技术和计算机网络技术的成熟和发展，工业控制领域又发生了一次技术变革。这次变革使传统的控制系统（如ＤＣＳ）无论在结构上还是在性能上都将发生巨大的飞跃，而这次变革的基础就是现场总线技术的产生［１］［４～５］。根据国际电工委? 0 Preface With the maturity and development of process control technology, automation instrumentation technology and computer network technology, a technological change took place in the field of industrial control. This change will make the traditional control system (such as DCS) tremendous leaps in structure and performance, and the basis of this change is the generation of field bus technology [1] [4 ~ 5]. According to the International Electrotechnical Commission?