What is Microcontroller, Microprocessor?

Before defining the Microcontroller¹, it is necessary to define the Microprocessor².

What is a microprocessor?

Microprocessor is an electronic circuit placed in a chip⁶ that forms the center of a Microcomputer³ system, performs arithmetic, logic⁴ operations, controls input-output⁵ units, produces the necessary control signals to ensure the correct operation of the system and provides coordination between units. In short, the microprocessor is the "Brain" that is at the center of all operations, everything revolves around it and is under its control.

The brain needs a lot of data⁷ to perform all these operations.

It would not be wrong to compare the microprocessor to the brain in the human body. The human brain is located in a dark skull, closed to the outside world, just like a chip, which is a completely closed environment. The brain has to make the necessary decisions for the healthy existence of the body it is in. It receives the necessary data to make decisions from data input sensors such as eyes, ears, skin, etc. that connect it to the outside world. In these data input sensors⁸, physical information such as vision, hearing, taste, contact, etc. coming from the outside world are converted into electrical signals and transmitted to the brain via nerve wires, which we can consider as data lines⁹. Then, the data received from this input information is evaluated and the desired task is decided. The movements required for the implementation of this decision are sent as electrical signals to output units such as hands, feet, and tongue via nerve wires in the same way. In the final stage, these electrical signals are converted into mechanical movements such as walking, holding, speaking, etc. and the process is completed. A cycle that we can summarize as:

Get Data-----Process-----Decide-----Implement

is repeated continuously as long as we are alive.

So the microprocessor is an electronic brain placed on a chip.

What is a microcontroller?

A microcontroller is a control chip formed by placing many different units such as one or more input-output units, one or more communication units, memory units, timers, etc. in a single chip.

What are the differences between Microprocessor and Microcontroller?

The microprocessor is a chip consisting of a single unit that only acts as a brain. Units such as input-output unit and memory unit are on separate chips and are optionally connected to the microprocessor with electrical lines.

The simplest example is PCs or laptops. In optional configurations called "Assembly" in daily life, the user connects a microprocessor of his own choosing (Intel Pentium, AMD etc.) and the hardware such as hard disk, display card etc. on the board suitable for it and creates the computer system of his own choice.

In the microcontroller, these peripheral hardware are not optional, they are fixed as embedded¹⁰ inside the chip. The user can only choose from different models of a microcontroller and cannot create his own configuration.

Why is such a distinction needed? What is it used for, where are they used?

We can make a rough generalization by saying that microprocessors are made for general purposes and microcontrollers are made for special purposes. With microprocessors, different computer systems can be created in many different combinations and with the freedom of hardware selection. They are generally produced for use in traditional computers used for home, office, scientific studies, etc. Due to their high speed, ability to connect to many peripherals¹¹, and ease of flexible configuration, they are suitable for computer systems used in daily life.

Microcontrollers are preferred more in industrial applications, in special systems used in production machines, and in places that do not require much speed, memory, etc. They are more resistant to environmental conditions. Since they are programmed with low-level languages¹² and generally do not need an operating system, they do not need large-capacity information storage units such as hard disks, high-value RAM¹³, etc. like traditional computers.

In short, since everything they usually need is in a single chip, they are cheap, simple, useful, and easy to program. A microcontroller can easily perform any operation that comes to mind, depending on the program written on it, with little or no need for hardware additions.

Topic summary

To make the subject easier to understand, let's summarize it with an example from the human body;

Microprocessor is the brain organ,

Microcontroller is the complete human body where all the organs such as brain, eyes, ears, mouth, tongue, arms, legs etc. are together.

The terms used in this article, their equivalents in terminology and meanings:

¹Microcontroller: Microcontroller

²Microprocessor: Microprocessor

³Microcomputer: Desktop, laptop, etc. computer system

⁴Logic: Logical

⁵Input-Output: (I/O): Units made of electronic circuits that the microprocessor uses to collect information from the real world or to send processed information to the real world.

⁶Chip, Integrated Circuit, (IC): A case or packaging system made of hard plastic, ceramic, etc. materials, created by combining many semiconductor materials and/or components in a small volume at micro or nano levels, where electronic circuits are placed, and which protects the circuit from external factors.

⁷Data: A set of information that can be processed or processed by the microprocessor and can be of different sizes

⁸Data input sensor: Electronic circuit or mechanical mechanism that converts physical quantities in the real world into electrical signals that the microprocessor can perceive.

⁹Data lines: A collection of conductive wires or lines that enable the transmission of data consisting of electrical signals from one point to another.

¹⁰Embedded: Placed in the chip

¹¹Peripheral unit: Units added to the computer system from the outside, such as a display card, network card, printer, screen, keyboard, etc.

¹²Low-level language: These are programming languages ​​closest to machine language, such as Assembly. It provides the most efficient use of existing memory and hardware by using the microcontroller's own code set.

¹³RAM: Random Access Memory. It is the memory unit where temporary information is kept. When the electrical power of the system is cut off, the information kept in this unit is lost.