Page 5 CFP

• Input Unit

  • uses input devices to accept the data and program
  • allow communication between  the  user  and  the  computer
  • In  modern  computers  keyboard,  mouse,  light  pen,  touch screen etc, are some of the input devices.
• Output Unit

  • have  an  interface  between  the  computer  and  the  user.
  • take machine coded output results from the processor and convert them into a form that can be used by human being.
  • In modern computers, monitors (display screens) and printers are the commonly used output devices 
• CPU (Central Processing Unit)

  ·         Brain of computer system

  ·         Makes decisions, calculations, directs computer functions

  ·         Consists of:

  -          Arithmetic and logic units

  -          Control unit

  -          Internal memory (registers)

  ·         Control unit coordinates system actions

  ·         Programs provide instructions to CPU

  ·         Bus pathway facilitates data transfer  between components
• Bus

  • A pathway which allows for the data transfer between them.
• Control Unit

  • Controls hardware operations
  • Coordinates input units, output units, memory unit, and processor
  • Arithmetic and Logic Units (ALU)
  • Perform addition, subtraction, division, multiplication, logical operations
  • Instructions and data stored in main memory for direct fetch and execution by processor
• Components of CPU:

  1.      Arithmetic and Logic Unit

  2.      Control Unit

  3.      Registers (internal memory)
• Arithmetic and Logic Unit (ALU):

   

  ·         Part of CPU where computations occur.

  ·         Consists of circuits for arithmetic operations and comparisons.

  ·         Takes data from registers inside the CPU for processing.

  ·         Registers are high-speed memories for immediate processing and results storage.