If you are new to embedded systems, you often remain confused between microcontrollers and microprocessors. It is one of the most asked questions in interviews too. Both terms are very intermingled and often used interchangeably. However, microcontrollers and microprocessors have many differences. This article will explain microcontrollers vs. microprocessors in simple words so you can easily differentiate these terms.
The microprocessor is a computer’s central processing unit that performs logical and arithmetic operations such as addition, multiplication, and subtraction like a brain in the human body. In comparison, the microcontroller is like a complete human body with arms, legs, and other parts for performing different tasks, taking instruction from the brain.
Microcontrollers are low-cost computers having a microprocessor and elements like Memory, serial ports, and other peripherals for performing various embedded systems tasks.
Keep reading this article, and we will clear your every query about microcontrollers and microprocessors in the simplest way. By the end of this article, you will be able to answer the difference between microcontrollers vs. microprocessors in any interview.
What is Microprocessor?
The microprocessor is a key component of any computer that performs all the computations. It helps the system in making decisions. It acts as the central processing unit of any computer that executes all the instructions passed to it. In simple words, it is the brain of the computer that process data and takes necessary steps for the proper functioning of the computer.
It is an electronic circuit having billions of transistors encapsulated in a single chip. This chip is clock-driven and programmable. It takes binary instructions from memory, processes them, and provides the results as output. You write the code to give instructions to the computer. This code is converted to binary first. Processors then process this binary code for controlling the application.
Microprocessors are usually differentiated depending on their clock frequency, the number of instructions executed per second, and the number of bits used per Instruction. The clock frequency of most of the processors is in Megahertz. Most processors use 32 or 64 bits per instruction nowadays.
When it comes to microprocessors, there are a few terms that you must know. These terms are the following
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Word Length:
It tells the number of bits a processor can process in one clock cycle. If a processor process 32-bit data in one clock cycle, its word length is 32. These are called 32-bit processors. This way, you can differentiate between 64-bit and 128-bit processors based on the word length.
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Clock Speed:
It is simply the speed at which a microprocessor executes instructions. If a microprocessor has a 32 MHz clock and each instruction takes one clock cycle to execute, it can execute 32 x 10^6 instructions in one second.
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Bus:
A bus communicates data and instructions between the processor and other peripherals like memory.
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Instruction Set:
It is a set of commands provided to the processor to tell what it needs to do. The most common instruction set is x86, which is used in most computers nowadays.
What is a Microcontroller?
The microcontroller is an integrated circuit that controls the task-specific embedded system using a microprocessor. In a microcontroller, the components such as ram, general purpose input outputs (GPIO), UART, SPI, and I2C that help the microprocessor to interact with the external environment come built-in within the chip.
Let’s suppose you want to automate your home. You will need a microcontroller for that. It will get data from devices like your AC via sensors connected with GPIOs. It will process the data obtained from the sensors with the help of a processor embedded inside it. The microprocessor will decide the actuator’s action based on the received data, as you instructed in your code.
In simple words, microcontrollers represent a complete system that gathers input, process it, and generates output based on the collected information.
We hope that the above example will clear your doubts about microcontrollers. Now let us see the definition of microcontrollers in a little technical word.
“It is a low-cost minicomputer designed to perform specific tasks in embedded systems. “
Let us now see some of the common terms used in microcontrollers.
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Peripherals:
You can define peripherals as a thing that helps microprocessors to communicate with external devices. For example, you want to turn on the light. The microprocessor will send a signal to GPIO. Consequently, GPIO will provide current to LED attached to it. Similarly, microcontrollers have many other peripherals to communicate with different types of external devices.
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Central Processing Unit (CPU):
The microprocessor used in the given microcontroller is called the central processing unit. We have done a detailed discussion about microprocessors above. So, we don’t need to discuss it anymore here.
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Random Access Memory (RAM):
It is a temporary storage available only when the microcontroller is powered on. It is used to store instructions and data in real-time.
Microcontroller vs. Microprocessor:
You have a clear idea about microcontrollers and microprocessors. Let us now see the difference in tabulated to get more clarity between these two terms.
Microprocessor |
Microcontroller |
It is a circuit that is used to execute instructions in the code. | It is a mini-computer that is used to control task-specific systems. |
It only does calculations. It does not have components like ram, memory, or GPIOs to interact with the external environment. You have to attach these things manually if you want to do so. | In a microcontroller, the components such as ram, GPIOs, UART, SPI, and I2C that help microprocessors to interact with the external environment come built-in within the chip. |
These are designed to run any application. | These are designed to run only specific applications. |
It is the heart of any computer system. | It is the heart of task-specific embedded systems. |
Programming a processor is difficult. | Programming a microcontroller is easier compared to microprocessors. |
It doesn’t have any external components, so power consumption is usually low. However, it doesn’t offer any power-saving modes. | Due to external components, the power consumption is higher. However, it comes with multiple saving modes to manage power depending on the load. |
Conclusion:
Microprocessor is just used to process data and instructions. However, the microcontroller is a complete package that uses a processor and other components to communicate with the external environment. Hence, they are used to control specific embedded systems.