Introduction to Microcontrollers and Their Applications

Click the blue text to follow us

1. Concept of Microcontroller

1. Name of Microcontroller

Microcontroller—Single Chip MicroComputer (SCMC)

Microcontroller Unit (MCU)

Embedded MicroController Unit (EMCU)

MicroComputer Development System (MDS)

In Circuit Emulator (ICE)

2. Two Branches of Microcomputers

• One is developing towards high-speed, large-capacity, and high-performance high-end microcomputers

• The other is developing towards stable, reliable, small-sized, and low-cost microcontrollers (mainly used for control)

3. Composition of Computer System

4. Hardware Composition of Microcomputer

5. Definition of Microcontroller

A microcontroller is a microcomputer that integrates the main components of a microcomputer onto a single chip.

It integrates the Central Processing Unit (CPU), Random Access Memory (RAM), Read-Only Memory (ROM), interrupt system, timer/counter, and I/O interface circuits onto one chip.

Microcontroller System Structure

Package Types of MCS51 Microcontroller

6. Similarities and Differences Between Microcontroller and PC

(1) Composition:

Same: CPU (for computing and control) RAM (data storage)

I/O ports (serial, parallel, etc.) ROM (program storage)

Different: PC: The above components are installed on the motherboard in chip form.

Microcontroller: The above components are integrated into a single chip.

(2) Functions:

Same: PC: Data computation, collection, processing, storage, transmission;

Microcontroller: Controls (or is controlled by) peripherals.

Different: General-purpose computers excel in data computation, collection, processing, storage, and transmission;

Microcontrollers specialize in measurement and control, often embedded in instruments/devices/systems to achieve intelligent effects.

(3) Application Characteristics:

Personal computers (microcomputers): Large size, high power consumption, high price, relatively fixed purpose, belong to general-purpose computers. Easy to learn and use, but when used for control, special interface cards must be made or purchased, and specialized application software must be developed.

Microcontroller: Dedicated computer.

7. Microcontroller System

The clock circuit, reset circuit, and extended memory, etc., together with the microcontroller form the microcontroller system.

Microcontroller Application System: Refers to the entire circuit system and software system that meets the requirements of the embedded object. On the basis of the microcontroller system, it adds object-oriented interface circuits, such as forward channels (sensor channel interface), backward channels (servo drive, control channel interface), human-computer interaction channels (keyboard, display, printer, etc.), serial communication ports (RS232), and application programs, etc.

2. Development and Application of Microcontroller

1. Development of Microcontroller

• Initial Stage of Microcontroller Development (1971-1976)

  Mainly focuses on 4-bit and 8-bit microcontroller early products. At this time, the manufacturing technology of microcontrollers was backward, the integration level was low, and they were mainly used in instruments, meters, consumer electronics, and calculators.

• Development Stage of Microcontroller (1976-1980)

  At this time, various 8-bit microcontrollers appeared, with Intel’s MCS-48 series microcontroller as a representative. This type of microcontroller adopted a single-chip structure, integrating the CPU and peripheral circuits onto one chip, using an 8-bit CPU, multiple parallel I/O ports, and an 8-bit timer/counter, but without a serial port. Its emergence marked the beginning of the separation between microcontrollers and general-purpose CPUs, forming new industrial controllers.

• Mature Stage of 8-bit Microcontroller (1980-1983)

  This stage is represented by Intel’s MCS-51 series microcontrollers, producing various high-performance microcontrollers. These microcontrollers integrated full-duplex serial communication ports and multiple 16-bit timers/counters. Storage capacity further expanded, and on-chip resources became richer, leading to widespread application.

• High-Performance Microcontroller Development Stage (After 1983)

  After Intel launched the 16-bit MCS-96 microcontroller in 1983, major manufacturers also introduced high-performance microcontrollers, with some reaching 32 bits. However, during this stage, 8-bit microcontrollers still had a large market application.

Divided by microcontroller bit:

• 4-bit Microcontroller Stage

  4-bit microcontrollers are mainly used in household appliances, electronic toys, etc.

• 8-bit Microcontroller Stage

  8-bit microcontrollers are widely used in industrial control, intelligent interfaces, instruments, and meters due to their strong functionality.

• 16-bit Microcontroller Stage

  16-bit microcontrollers can be used in high-speed complex control systems.

• 32-bit Microcontroller

  In recent years, various computer manufacturers have entered the development and production stage of higher-performance 32-bit microcontrollers. Due to the not-so-urgent demand for 32-bit microcontrollers in the control field, their application is not very widespread.

Currently, the mainstream model widely used is the 80C51 series 8-bit microcontroller.

2. 80C51 Series Microcontroller

Today’s 80C51 is not limited to Intel, but refers to all models compatible with 80C51 based on the 8051 core.

MCS-51 Microcontroller Series

3. Comparison of 80C51 and 8051

(1) MCS-51 series chips use HMOS (High-density short-channel MOS) technology, while 80C51 chips use CHMOS (Complementary Metal-Oxide-Semiconductor HMOS) technology. CHMOS technology is a combination of COMS and HMOS, featuring high density, high speed, and low power consumption.

(2) 80C51 chips are characterized by low power consumption. For example, the power consumption of the 8051 chip is 630mW, while that of the 80C51 is only 120mW.

(3) The 80C51 adds two working modes of standby and power-down protection to ensure that the microcontroller can maintain the lowest current consumption during power-down.

(4) In addition, among the 80C51 series chips, the internal program storage includes not only ROM and EPROM types but also E2PROM types. For example, the 89C51 has 4KB E2PROM. With the improvement of integration technology, the capacity of the internal program storage of the 80C51 series chips has also increased, and there are now chips with 64KB capacity. Moreover, many 80C51 chips have program storage security mechanisms to prevent application program leakage or duplication.

4. Application of Microcontroller

Application Scope:

• Mechatronics
• Industrial Control: CNC Machine Tools, Industrial Robots, Temperature Control
• Instruments
• Household Appliances
• Information and Communication Products
• Military Equipment

Application of Microcontroller

Long press the image to follow

Discover more exciting content

WeChat ID: Mechanical-knowledge