What is a microcontroller and what does it do?

Microcontroller is a complete computer system integrated on a single chip. Although most of his functions are integrated in a small chip, but it has a complete computer needs most of the components: CPU, memory, internal and external bus system, most of the current will have external memory. At the same time integrated peripherals such as communication interfaces, timers, real-time clock. And now the most powerful microcontroller system can even be sound, image, network, complex input and output systems integrated into a chip.

A microcontroller is also known as a microcontroller because it was first used in the field of industrial control. Microcontrollers evolved from specialized processors that had only a CPU on a chip. The earliest design concept was to integrate a large number of peripherals and CPU in a chip, so that the computer system is smaller and easier to integrate into the complexity of the requirements of the strict mention of the control equipment, INTEL's Z80 is the earliest in accordance with the idea of the processor design, from then on, the development of microcontrollers and specialized processors will be separated.

Early microcontrollers were 8-bit or 4-bit. One of the most successful was INTEL's 8031, which received great acclaim for its simplicity, reliability, and good performance. Since then, the MCS51 series of microcontroller systems have been developed on the 8031. The microcontroller system based on this system is still widely used until now. With the improvement of the requirements of the industrial control field, 16-bit microcontroller began to appear, but because of the price-performance ratio is not ideal and has not been widely used. 90's with the development of consumer electronics products, microcontroller technology has been greatly improved. With the INTEL i960 series, especially the later ARM series of widely used, 32-bit microcontroller to rapidly replace the high-end status of 16-bit microcontroller, and enter the mainstream market. The performance of the traditional 8-bit microcontroller has also been improved rapidly, and the processing power has been increased hundreds of times compared with that of the 80s. At present, the high-end 32-bit microcontroller main frequency has exceeded 300MHz, performance to catch up with the mid-90's dedicated processor, while the ordinary model factory price fell to 1 U.S. dollars, the highest-end model is only 10 U.S. dollars. Contemporary microcontroller systems are no longer developed and used only in bare-metal environments, and a large number of specialized embedded operating systems are widely used on a full range of microcontrollers. The high-end microcontrollers used as the core processing of PDAs and cell phones can even directly use dedicated Windows and Linux operating systems.

Microcontrollers are best suited for embedded systems than dedicated processors, which is why they are the most widely used. In fact microcontrollers are the most numerous computers in the world. Microcontrollers are integrated into almost every electronic and mechanical product used in modern human life. Cell phones, telephones, calculators, household appliances, electronic toys, palmtop computers, and computer accessories such as mice are equipped with 1-2 microcontrollers. Personal computers also have a number of microcontrollers working in them. Automobiles are generally equipped with more than 40 microcontrollers, and complex industrial control systems may even have hundreds of microcontrollers working at the same time! The number of microcontrollers not only far exceeds the combined number of PCs and other computing, but is even greater than the number of humans.