UNIT 2.2 CENTRAL PROCESSING UNIT

UNIT 2.2 CENTRAL PROCESSING UNIT

THE CENTRAL PROCESSING UNIT

KNOWN AS PROCESSOR

JUST AS WE HAVE OUR BRAIN COMPUTERS HAVE PROCESSOR.

Analogy

• comparison of human and computer

• brain

• input

• output

• operating system

Functions of CPU

• process instructions of the software ( for example in loading a program)

• handle control signals coming for example coming from input and output devices

• carry out arithmetic and logical operations

• to store data

Two parts of CPU

• Arithmetic and logic unit (ALU)

• Control unit (CU)

• 
  

• 
  

CPU

• CPU is a chip

• made up of transistors

• transistors are like switches

• the transistor turns on and off to store binary values

How Computers

Represent Data

•Binary numbers

oOnly 0s and 1s

•Bit

oSmallest piece of data a computer can work with

oEither “on” or “off,” a 0 or a 1

oEight bits—byte—a single unit of storage

What is the formula to calculate speed ?

How can we measure computer's speed?

SPEED

no of instructions/ second

measured in Hertz

Ghz or Mhz.

Video on inside the computer unit.

https://www.youtube.com/watch?v=HB4I2CgkcCo

Inside the System Unit

Motherboard

CPU

Power supply

Cooling fan

Expansion slots

RAM

BIOS/ ROM

hard drive

I/O ports

clock chip

CD/DVD Drive