应用STEP7复杂数据类型实现查表程序

Realize the Table Look-up Function by Using the Complex Data Type of STEP7

在自动控制系统的算法实现中,查表是一种非常有用的操作,PLC实现模糊控制、专家系统等先进控制方法都需要查表。但目前大多数PLC都没有提供现成的查表指令,实现查表程序都比较麻烦且效率低下。探讨如何通过西门子S7系列PLC使用STEP7复杂数据类型及复杂参数类型,实现间接寻址的查表程序。

The Table Look-up function is a kind of very useful operation in the algorithm of automatic control system.In the PLC system,there need the Table Look-up function to realize fuzzy control,expert system and other advanced control methods.But at present most of the PLC does not provide a readymade look-up table command,realize the look-up table procedure is more troublesome and ineffective.In this paper,we use the complex data type and the complex parameter type of STEP7 to realize the Table Look-up function in the s Siemens S7 series PLC.