描述
堆栈是计算机中最常用的一种数据结构,遵循先入后出的原则,一般用于保存数据。在S7-200PLC中涉及堆栈操作的指令有以下三种,最后本文给出了梯形图应用实例。逻辑入栈(LPS,LogicPush)指令复制栈顶的值并将这个值推入栈顶,原栈顶中各级数据依次向下一级推移,栈底值被推出丢失。
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