Definition and Functions of Microcontroller

By | August 14, 2021

Definition of Microcontroller

Microcontroller is a mini computer device (micro) which is packaged in a single chip IC (Integrated Circuit) and has a certain operating program in it. The components on this microcontroller are almost similar to a Personal Computer (PC).

The microcontroller in addition to having a Central Processing Unit (CPU), is also equipped with RAM, ROM components, as well as input and output devices (IO ports) that can be programmed as needed.

So, in simple terms the microcontroller is a small chip that integrates a number of components and is able to work according to needs after being filled in by the program.

Microcontroller has a small and simple form because it is designed only to carry out one specific or special function in managing a system. To perform the functions in a system, the microcontroller is given a program that is created manually by humans with certain arrangements and interests.

Microcontroller Function

The main functions of the microcontroller are as follows:

  • As a timer
  • As an oscillation generator
  • As a flip-flop
  • As ADC (Analog Digital Converter)
  • As Counter
  • As a Decoder and Encoder

Main Components of Microcontroller

The basic principles of the 3 main components in the Microcontroller are:


  1. Memory


The memory part of the microcontroller is composed of ROM and RAM:

  • ROM (Read-Only Memory), is a type of memory that serves to permanently store the program that is being operated. The size of the program will depend on how much memory size. Rom memory is a type of non-volatile memory where the stored data will not be lost when the power supply is turned off. So that this memory acts as the main program storage of a system.
  • RAM (Random Access Memory) is a type of memory that serves to temporarily store data. Memory data in RAM will be deleted and lost automatically when the power supply is turned off. For this reason, the main programs in a system are never stored in RAM memory.
  1. Input and Output (I/O)


The Input Output section of the microcontroller functions as a liaison between the CPU and input equipment such as sensors or transducers and also as a liaison with output devices such as actuators. The I/O unit also acts as a communication channel between the CPU system and external systems.

  1. Central Processing Unit (CPU)

CPU is a vital part or brain of a microcontroller. The function of the CPU on the microcontroller is to coordinate all computational operations, perform arithmetic and logic operations, and control the work system as a whole.

Use of Microcontroller in Life

Microcontrollers have been widely used in various household and commercial equipment. In addition, this component is also widely applied to cars, vehicles or an industry that makes it a central part of industrial robotics. Because this component controls a single program and executes simple instructions, it does not require large processing power.

  • In the field of decoration or decoration, it is applied to making running text or running LEDs.

  • In the industrial sector, the use of microcontrollers is found in temperature sensors/temperature counters on conveyor machines, robotic arms, and so on.
  • In households, microcontrollers can be used for digital clocks or timers and much more.

Microcontroller Features and Characteristics

Microcontroller has several characteristics including:

  1. CPU Capability Not Too High

Unlike the CPU in general, the CPU microcontroller is very simple which can only do or process a few commands or programs. Although currently in line with technological developments, microcontrollers are produced with more sophisticated specifications but in fact have not been able to match the capabilities of general CPUs in processing data from software.

  1. Small Internal Memory

In addition to its small shape and size, the internal memory on the microcontroller also has a fairly small amount. The large internal memory capacity of the microcontroller contains only the size of Bit, Byte or Kilobyte.

  1. There is Non-Volatile Memory

In the microcontroller there is a Non-Volatile memory, where a command or program that has been created can be deleted or re-created. Not only that, all data that has been stored in the Non-Volatile memory of the microcontroller will not be lost when it does not get a supply from the power supply.

  1. Simple Commands

A microcontroller can only process specific commands or programs. However, nowadays there are also many microcontrollers that have undergone sophisticated development.

  1. Programs/Commands Directly Connect to I/O Ports

The I/O port is one of the main components which has an important role as a way of communication. Basically all commands or programs are directly related to the I / O port because of its role as a communication link between input devices and output devices.

Difference between Microcontroller and Microprocessor (CPU)



Basically in terms of words, there are different meanings of these two components. “Controller” on the microcontroller and “Processor” on the Microprocessor.

From the two words above, it can be interpreted that the Microcontroller is a Small Controller while the Microprocessor is a Small Processor. Of course here it is clearer, than “processing” and “controlling”. What is processed or controlled? of course a given program or command.

Based on Function

Judging from its function, the microcontroller serves to control or control a system in the device based on data stored in Read Only Memory (ROM).

While the microprocessor or what is often referred to as the CPU (Central Processing Unit), has more general and more functions, such as data retrieval and calculation, performing calculations and data manipulation, and storing the results of processing or calculating the data and programs for later realization and displayed in a form.

Based on the Forming Components

Microcontroller is composed of several components such as CPU or Central Processing Unit (ALU, CU), Memory (RAM and ROM), Port I / O and Counter time. While the microprocessor is made of 3 main components, namely the Arithmetic Logic Unit (ALU), Register Unit (RU) and Control Unit (CU).

The advantage of a microcontroller over a microprocessor is that the number of components and the design costs of the items being controlled can be kept to a minimum. Microcontrollers are generally designed using CMOS (Complementary Metal Oxide Semiconductor) technology, which is an efficient integrated chip (IC) manufacturing technology that uses less power and is stronger against electrical surges.