FANDOM COMPUTERS

          CLASSIFICATIONS OF COMPUTERS

Microcomputer
  Microcomputer is at the lowest end of the computer range in terms of speed and storage  capacity.

          EX: Desktop, Laptop, Tablet PC, Smart Phones. 


Mini Computer
       •This is designed to support more than one user at a time. (up to 200 users)

       •It possesses large storage capacity and operates at a higher speed.

       •This type of computer is generally used for processing large volume of data in an organisation.

       EX: Servers in Local Area Networks (LAN).

Mainframes
          •They operate at very high speed, having very large storage capacity and can handle the work load of many users(more than 200 users.
          • They are generally used in centralized databases.
Supercomputers
         •They are the fastest and most expensive machines.
         • They have high processing speed compared to other computers
         •They have also multiprocessing technique.
         • Supercomputers are mainly being used for whether forecasting, biomedical research, and other areas of science and technology


      BASIC ORGANISATION OF COMPUTER
INPUT
     The input unit is used to feed information or instruction to the computer.
Input Devices:

                •Keyboard

                •Mouse

                •Scanner…

MEMORY UNIT

Used to stor
•Data
•Instructions
•Intermediate Results &
•Final Processed Results

Types:

 •Primary

 •Secondary

    •Internal Processor memory
            Primary memory is used to store temporary data.
                      EX:RAM, ROM etc,.
            Secondary memory is used to store information permanently
                       EX:Hard disk.
             Internal Processor memory is used to store temporary processor data
                        EX:CPU Registers

          CENTRAL PROCESSING UNIT (CPU)

   Responsible for processing the data & instruction and controlling all other components
Operation (4 Phases)
     •Fetching Instruction from the memory
     •Decoding the instruction
     •Executing the instructions
     •Storing the results in to the memory
It contains the following components
       •CONTROL UNIT
       •ALU
       •MEMORY

•CONTROL UNIT
        –It controls all other units in the computer.
        –It directs the sequence in which operations to be performed.
        –It also controls the flow of data between various units.

ARITHMETIC & LOGICAL UNIT
        –It performs all arithmetic & logical operations.
        –i.e. arithmetic operations like addition, subtraction, multiplication, division etc,. And        logical operations like AND,OR,NOT etc,.
Registers
       –CPU contains a few special purpose, temporary storage units called registers
      –They are high speed memory locations
      –Used for handling instructions, data & intermediate results that are currently being processed
Registers
  1.Program Counter(PC)
  2.Instruction Register(IR)
  3.Memory Address Register(MAR)
  4.Accumulator
OUTPUT
  –The output unit is used to display the result of the process.
  –Data processed by CPU is made available to the end user by O/P devices
  –Commonly used O/P devices:
            •Monitor
            •Printer
            •Speaker
                     Components of Computers

•Hardware
      The physical components present in the computer.
•Software
        It is a collection of programs and it can perform some operations.
Components Present inside the cabinet
        •Motherboard
        •Processor
        •SMPS
        •Disk drives
        •RAM & ROM etc,.

                             NUMBER SYSTEM

•Number System
        –A computer is a digital system that stores and process data in the form of 0’s and 1’s(Binary/Machine language)
       –Hence there is a need to change the data in the form of 0’s &1’s
•Positional Number System
         –Numbers are represented using some symbols called digits and the values of these no’s can be determined by taking the position of digits

Categories:

    •Decimal System

    •Binary System
    •Hexa Decimal System
     •Octal System

Decimal System
   –Uses 10 as a base & is called base 10 no system
   –10 symbols are available for representing values (0-9)
   –Used to represent both integer & floating point values
Representation
    –6543.12410
   –(6x10^3)+(5x10^2)+(4x10^1)+(3x10^0)+(1x10^-1)+(2x10^-2)+(4x10^-3)
    = 6543.12410

Binary System
   –Uses 2 as a base & is called base 2 no system
    –2 symbols are available for representing values (0 & 1)
Representation
   –101001.01012
   –(1x2^5)+(0x2^4)+(1x2^3)+(0x2^2)+(0x2^1)+(1x2^0)+(0x2^-1)+(1x2^-2)+(0x2^-3)+  (1x2^-4)
   = 41.312510

Hexa Decimal System

   –Uses 16 as a base & is called base 16 no system
   –16 symbols are available for representing values (0-9 & letters A,B,C,D,E,F)

Representation

   –4A9.2B16

  –(4x16^2)+(10x16^1)+(9x16^0)+(2x16^-1)+(11x16^-2)
   = 1193.167910

Octal System

   –Uses 8 as a base & is called base 8 no system
    –8 symbols are available for representing values (0-7)
Representation
   –215.438
  –(2x8^2)+(1x8^1)+(5x8^0)+(4x8^-1)+(3x8^-2)
   = 141.546910

       

                         THANK YOU!!!!!