1.plc is a product based on single chip microcomputer, which is a programmable integrated chip. In other words, plc is composed of single chip microcomputer and peripheral circuits. The development of single chip microcomputer is more troublesome. Programming with assembly or C language, such as using single chip microcomputer to delay, is calculated from crystal oscillator, but PLC is different. Each manufacturer provides a programming software, which can be programmed with ladder diagram, and the delay only needs time relay.

2. Single-chip microcomputer can form various application systems, from micro, small to large and medium-sized ones. PLC is a special case of single chip microcomputer application system. Single chip microcomputer can develop all kinds of intelligent instruments, such as temperature controller, TV remote controller, soymilk controller, microwave oven, intelligent toys and so on.

3. The plc of different manufacturers has the same working principle, similar functions and indexes, and has certain interchangeability, universality and reliability. PLC is a computer specially developed for industry.

4. The development cost of single chip microcomputer is low, from ten to dozens, even hundreds, but it is more troublesome to develop. The price of PLC is hundreds, thousands and tens of thousands, but the development cycle is short and the effect is quick. high reliability