Profibus-DPV1信息循环时间研究

Research on information circulation time in Profibus-DPV1

在分析Profibus现场总线协议DPV1和DPV0基础上,将DPV0升级为DPV1。通过对DPV1功能及主从服务点类型的研究,对影响信息循环时间的8种DPV1时间参数进行计算,并分析了信息循环时间的计算方法。实际应用结果表明:DPV1协议下最长的数据更新时间是DPV0协议下的3倍;某一时刻用户程序通过DPV1协议访问DPV1从站的数量越多,则数据通信速率就越慢,因此用户程序尽可能不在同一时间对总线所有设备进行非循环数据访问。

On the basis of analyzing Profibus protocol of DPV1 and DPV0,the DPV0 was upgraded to the DPV1.By investigation on the DPV1 function and master slave service type,eight kinds of DPV1 time parameters affecting the information cycle time were calculated,and the calculation method for information cycle time was studied.The practical application results indicated that,the longest data update time in DPV1 protocol was three times larger than that in DPV0 protocol.The more the slave stations that the user program accessed the DPV1 via DPV1 protocol at the same moment,the slower the data communication rate.Therefore,the user program should conduct non cycle data access to all equipments in bus at different times as much as possible.