PLC的工作方式和通用微机不完全一样，因此用PLC设计自动控制系统与微机的控制系统的开发过程也不完全一样。需要根据PLC的特点，以程序形式来体现其控制功能。-PLC work and general-purpose microcomputer is not exactly the same, with the the PLC design of automatic control system with microcomputer control system development process is not exactly the same. According to the characteristics of the PLC to the program in the form to reflect its control function.