目录摘要第1章引言..............................................................................................................................11.1设计概述及其背景.........................................................................................................11.1.1设计要求.............................................................................................................11.2设计目标与意义.............................................................................................................11.3章节安排.........................................................................................................................2第2章方案论证与选型..........................................................................................................32.1设计任务分析.................................................................................................................32.2方案论证与选择.............................................................................................................32.2.1方案一.................................................................................................................32.2.2方案二.................................................................................................................32.3方案确定.........................................................................................................................3第3章硬件电路设计............................................................................................................43.1原理分析.........................................................................................................................43.1.1外部电路基本组成框图.....................................................................................43.2I/O端口的分布..............................................................................................................53.3I/O接线图......................................................................................................................63.4PLC的介绍....................