Components of Computer
In Computer Science, Computer architecture deals with the functional behavior of a computer system as viewed by a programmer. It can also be described as the logical structure of the system unit that housed electronic components. The first computer architecture was introduced in 1970 by John Von Neumann.
Basic Components of Computer
There are 4 main computer components that are given below:
- Input Unit
- Central Processing Unit (CPU)
- Output Unit
- Memory Unit
- Input Unit – The computer accepts coded information through input unit by the user. A computer will only respond when a command is given to the device. These commands can be given using the input unit or the input devices. E.g. Keyboard, Mouse etc.
The data entered can be in the form of numbers, alphabet, images, etc. The input unit works as a fundamental part of the entire computer system.
An input Unit performs the following functions-:
- It accepts the instruction and data from the outside world (User).
- It convert these instructions and data to a form acceptable to computer.
- Its supplies the converted data and instruction to the computer system for further processing.
2. Central Processing Unit (CPU)
The main chip in a computer is the microprocessor chip, which is also known as the CPU (central processing unit). CPU is also often called the brain of Computer. The CPU is mounted on a printed circuit board called the main board or mother board.
Motherboard :- The main circuit board contained in any computer is called a motherboard. it is also known as the main board or logic board or system board. All other electronic devices and circuits of computer system are attached to this board like RAM,ROM,PCI, Expansion slots and USB Ports. It also include controllers for device like the hard drive, keyboard, mouse and DVD drive.
CMOS battery, BIOS chip, fan, expansion slot, SMPS,PCI slot, buses are main components of mother board.
This chip is considered to be the controlling chip of a computer system since it controls the activities of other chips as well as outside devices connected to the computer, such as monitor and printer. In addition, it can also perform logical and computational tasks.CPU consists of a set of registers, arithmetic logic unit(ALU) and control unit(CU), which together interpret and execute instructions in assembly language.
Registers :-These are temporary storage elements that facilitate the functions of CPU. These are used to quickly accept, store and transfer data and instructions that are being used immediately by the CPU.
The primary function of CPU are as follows -:
- A CPU controls all the internal and external devices.
- CPU transfer instructions and input data from main memory to register.
- It executes the instructions in the stored sequence.
- When necessary, CPU transfers output data from registers to main memory.
- CPU also performs arithmetic and logic operations.
- The CPU consist of following main sub-systems: .
The CPU consist of following main sub-systems:-
i) Arithmetic Logic Unit (ALU) – ALU is a part of the CPU where various computing functions are performed on data.ALU uses registers to hold the data that is being processes. The ALU performs the following operation.
- Arithmetic Operations – Addition, Subtraction, Multiplication and Divisions.
- Logical Operations – AND, NOT,OR, XOR.
- Comparison Operations – = ,<,<=,>,=>
- Bit-shifting Operations.
ii) Control Unit – It controls the entire operations of a computer. it is like a supervisor which controls the flow of data between the CPU, Memory and input/output devices. It directs the computer to carry out stored program instructions by communicating with the ALU and registers.
The basic function of control unit is to fetch the instruction stored in the main memory, identify the operations and devices connected involved in it and accordingly generate controls signals.
3. Memory Unit
When we enter the data into the computer using an input device, the entered information immediately gets saved in the memory unit of the Central Processing Unit (CPU). Because of the presence of some existing programming, the Memory Unit transmits the data further to the other parts of the CPU.
Similarly, when the output of our command is processed by the computer, it is saved in the memory unit before giving the output to the user.
Memory unit is responsible to store programs or data on a temporary or permanent basis. Memory unit is of two types primary and secondary memory. The primary memory is used to store the programs and data when instructions are ready to execute. The Secondary memory is used to store the data permanently.
The primary memory or temporary memory or main memory is volatile in nature that means the content is lost when power supply is switched off. The Random Access Memory(RAM) is an example of primary memory.
The Secondary memory or Permanent memory is non volatile in nature that means content are available even after the power supply is switched off. Hard disk are an example of this memory.
4. Output Unit – Output unit receives the information from CPU and then delivers it the external storage or devices in a human-readable form. The devices which are used to display output to user are called Output Devices. Monitor and Printer are common example of Computer.
Output unit performed the following function -:
- It accepts the results produces by computer system which are in the coded form and hence cannot be easily understand by user. So Output unit converts these coded results to readable form which are human-readable.
- It produces the converted results to the user by output devices e.g. monitor, printer, plotter etc.
