【摘要】 本文介绍了现场总线的特点，通过Ｓ７－２００基于ＰＲＯＦＩＢＵＳ现场总线标准的ＰＰＩ通讯协议在工程中的实际应用例子，进一步描述了现场总线技术在具体工程中发挥的作用。更多还原

【Abstract】 This paper introduces the characters of fieldbus, it provides a act application example of using the PPI communication protocol based upon the PROFIBUS presents by siemens s7-200PLC, further to describe detailed the advantage by using the fieldbus in a project.更多还原