In this article, we will learn about the 6 major components of the Central Processing Unit, which is commonly known as the brain of the computer.
The Central Processing unit (C.P.U) is responsible for all the major tasks that happens on a computer system like processing data and instructions.

However, these very vital functions of the C.P.U won’t be possible without the components present inside the C.P.U; which divide all the workload among themselves and process them at a very fast pace to produce the desired result.

Components of CPU and Their Functions

1. Control Unit (CU)
The control unit is responsible for controlling the way input and output devices, the Arithmetic and Logic Unit, and the computer’s memory (RAM) etc. send instruction to the C.P.U and as well as how they receive instructions from the C.P.U. The Control Unit fetches the instruction, converts it in a decoded form, and then sends it for processing to the computer’s processor, where the desired operation is performed.

Major Functions of The Control Unit

• It is responsible for controlling the sequence in which instructions move in and out of the processor. And also, the way these instructions are performed.
• It is responsible for fetching the input, converting it into signals, and storing it for further processing.
• It controls how the other components of the C.P.U functions such as the ALU and the Registers.

2. Arithmetic Logic Unit (ALU)
The Arithmetic and Logical Unit is responsible for all the arithmetical and logical calculations or operations as well as taking important decisions in the system. It is also known as the mathematical brain of the computer. The ALU makes use of the registers for its calculations. It takes input from input registers, performs operations on the data, and stores the output in an output register.

Major Functions of ALU

• It is mainly used to make decisions like performing arithmetic and logical operations.
• It acts as a bridge between the computer’s primary memory (RAM) and the secondary memory (e.g: Hard Drive).
• All the information that is exchanged between the primary and secondary memory passes through the ALU.

3. Registers
Registers are a part of a computer’s memory that is used to store the instructions temporarily to provide the processor with the instructions at times of need.

Please note that There are various kinds of registers that perform different functions. Viz

Input Register, Output Register, Temporary Register, Address Register, The Program Counter, Data Registers and Instruction Register.

• Input registers are used to carry the input signals.
• Output registers are used to carry the output signals.
• Temporary registers store data temporarily.
• Address registers store the address of the memory.
• The program counter stores the address of the instructions.
• Data registers hold the memory operand.
• Instruction registers hold the instruction codes.

4. Cache Memory

Cache is a type of Memory which is closer to the C.P.U than the Random-Access Memory (RAM). It stores small amount of data and instructions that is frequently used; This technique is used instead of fetching these frequently used instructions from the RAM all the time; thus, reducing the amount of time needed to fetch and execute instructions.

Functions of Cache:

• They reduce the amount of time needed to fetch and execute instructions.
• They store data temporarily for later use.

5. Buses
A bus is a link between the different components of the computer system and the processor (I refer to it as the messenger of the CPU). They are used to transmit or carry signals and data from the processor to different devices and vice versa.

There are three types of buses Viz.

• Address Bus:  this is used for sending memory address from processor to other components.
• Data Bus: this is used for sending the actual data from the processor to the components.
• Control Bus: this is used for sending control signals from the processor to other devices.
   

Functions of Bus:

• It is used for sharing data between different devices.
• It supplies power to different components of the system 

6. Clock
The clock controls the timing and speed of different components of the CPU and as well maintains the synchronization between all these components of the computer system. It is responsible for sending out electrical signals which regulate the timing and speed of these functions.
The clock speed of everyC.P.U has a major impact on the speed at which programs load and how smoothly they can run.

In general, a higher clock means a faster C.P.U. However, there is an exception to this in term of C.P.U Mode such as Intel and AMD, number of cores Etc.

A C.P.U with a clock speed of 1.6 GHz will mostly execute up to 3.2 billion cycles per second.