EDA technology has the widest range, including single-chip computers, many languages used C, VHDL, etc. EDA is a relatively macroscopic technology. The single chip microcomputer is actually the use of a chip, the smallest system. The common microcontroller programming C language details the principles of the microcomputer chip and the working principle of the system, more refined, involving the specific data transfer of the chip, computing, storage, and so on, the micro. Often used is assembly language PLC this is not quite understood, as if it is the control of strong electricity... This is my understanding