PLC指令代码的文法分析和翻译

Syntax Analysis and Translation of PLC's Code

提出并实现了一个把ＰＬＣ指令代码转换为梯形图的文法分析与翻译系统。基本思想是构造ＰＬＣ指令的上下文无关文法，并利用语法制导翻译得到梯形图的二叉树表示，同时给出了梯形图的计算机内部表示和从二叉树表示转换为计算机内部表示的算法。

A syntax analysis and translation system is proposed in this paper for translation from PLC's code to relay ladder diagram. An essential idea here is constructing context free syntax of PLC's code, and getting it's binary tree representation by using the method of syntax binary tree to relay ladder diagram are also given in the paper.