基于AOV图及因果图的梯形图与语句表互换算法

Transformation Algorithm Between Ladder Diagram and Statement List Based on AOV Diagraph and CE Diagraph

结合AOV图与因果图提出了一种新的梯形图与语句表双向转换算法。一方面,将梯形图转化为AOV图,并利用AOV图建立因果图,然后遍历因果图的节点生成PLC所能识别的语句表;另一方面,将语句表转化为因果图,基于因果图生成梯形图。经过实际编程证明,该算法简洁,实用性及通用性好,并成功应用于某国产化PLC开发中。

Transformation algorithm between the ladder diagram and the statement list based on the AOV diagraph and the cause and effect diagraph for programmable logic controller （PLC） systems is proposed. The ladder diagram is transformed to the AOV diagraph, then the statement list is created by traversing the node in cause and effect diagraph. On the contrary, the statement list is transformed to cause and effect diagraph, then the ladder diagram is generated based on cause and effect diagraph. Proved by programming, the algorithm is compact, practical, universal, and it is successfully used in the development of a domestic PLC system.