👉 BASIC COMPUTER 👈

•  INPUT UNIT
•  OUTPUT UNIT
•  STORAGE UNIT
•  ARTHMETIC LOGIC UNIT 
•  CONTROL UNIT 
•  CENTRAL PROCESSING UNIT 
• CONCEPT

input unit :

Data  and instruction must enter a computer system before the computer can perform any computation on supplied data . The input unit that a links a computer with its external environment perform this task.

An input unit performs following functions;

• it accepts (or reads) instruction and data from outside world .
• it converts these nst4ruction and data in computer acceptable form. Units called input interfaces accomplish this task.
• it supplies the converted  instruction an data to the storage unit for storage and further processing.

output unit :

An output perform the reverse operation of that of an input unit . It supplies information obtained from data processing to outside world .

An output unit performs following functions;

• It accepts the produced results, which are in coded form. We cannot understand the  coded results easily.
• it converts these coded results to human acceptable ( readable ) form. Unit called interface accomplish this task.
• it supplies the converted results to outside world.

storage unit :

 storage unit of a computer system holds data and instruction to be processed and intermediate and output results of processing. 

storage unit of all computers is comprised of following two types of storage . 

primary storage :

primary memory is internal memory of the computer.  It is also known as main memory and Temporary memory .Primary Memory holds the data and instruction on which computer is currently working. Primary Memory is nature volatile. It means when power is switched off it lost all data.
Types of Primary Memory– Primary memory is generally of two types.

1. RAM
2. ROM

Secondry storage :

Secondary Memory is external memory of the computer. It is also known as Auxiliary memory and permanent memory. It is used to store the different programs and the information permanently. Secondary Memory is nature non volatile. It means data is stored permanently even if power is switched off.

The secondary storage devices are:

1. Floppy Disks
2. Magnetic (Hard) Disk
3. Magnetic Tapes
4. Pen Drive
5. Winchester Disk
6. Optical Disk(CD,DVD)

Arthmatice logic unit (ALU) :

An arithmetic logic unit (ALU) is a digital circuit used to perform arithmetic and logic operations. ... The control unit tells the ALU what operation to perform on that data, and the ALU stores the result in an output register. The control unit moves the data between these registers, the ALU, and memory

The ALU has two main functions: It performs arithmetic and logical operations (decisions). The ALU is where calculations are done and where decisions are made. It acts as a gateway between primary memory and secondary storage .

control unit :  

The control unit is a part of the Central Processing Unit (CPU). The CPU is divided into the arithmetic logic unit and the control unit. 

The main function of a control unit is to fetch the data from the main memory, determine the devices and the operations involved with it, and produce control signals to execute the operations.

• It helps the computer system in the process of carrying out the stored program instructions.
• It interacts with both the main memory and arithmetic logic unit.
• It performs arithmetic or logical operations.
• It coordinates with all the activities related to the other units and the peripherals.
  
  
  

CENTRAL PROCESSING UNIT (CPU):

Contyrol unit and arthmatice logic unit of a computer  system of together known as the central processing unit . It is the brain of a computer system . In human body, the brain takes all major decesions and other  parts of the body function as directed by the brain , Similarly , in a computer system , the CPU performs all major calculations and the comparisons ,and also activites and controls the operation of other units of the computer system .

 

concept :