软PLC梯形图到指令表的转换方法研究

软PLC是一种新型的控制技术,即利用软件实现传统PLC的功能。梯形图转换指令表是软PLC技术中一个关键点,文章通过AOV和拓扑排序、AOV和串并联扫描、正向深度优先扫描、二叉有向图四种方法实现梯形图到指令表的转换,同时介绍四种方法优缺点。

Soft PLC is a new type of control technology, which uses software to realize the function of traditional PLC. The con-version of ladder diagram into instruction table is a key point in soft PLC technology. In this paper, four methods, i.e., AOV and topological sorting, AOV and series-parallel scanning, forward depth-first scanning and binary digraph, are used to realize the conver-sion from ladder diagram into instruction table. At the same time, the advantages and disadvantages of the four methods are intro-duced.