M3&M4 Introduction to Computing

System Unit is

a case that contains electronic components of the computer used to process data.

The inside of the system unit on a desktop personal computer includes:

• Drive bays

• Power supply

• Sound card

• Video card

• Processor

• Memory

Motherboard is

The main circuit board of the system unit

Computer chip contains

integrated circuits

Processor

Also called the CPU, interprets and carries out basic instructions that operate a computer

Processor contains

contains control unit and arithmetic logic unit (ALU)

Types of processors

• Multi-core Processor

• Dual-core Processor

• Quad-core Processor

The control unit is

component of the processor that directs and coordinates most of the operations in the computer

arithmetic logic unit (ALU)

performs arithmetic, comparison and other operations

Processor repeats a set of four basic operations which comprise a machine cycle

• 1. Instruction is fetched from a cache or ram

• 2. Instruction is decoded into a form the ALU or FPU can understand

• 3. ALU or FPU performs a computation according to the instruction

• 4. Data/Results from the instruction execution stored in RAM

Pace of the system clock is called

Clock speed and it is measured in gigahertz

System clock controls

Timing of all computer operations

Memory

consists of electronic components that store instructions waiting to be executed by the processor, data needed by those instructions, and the results of processing the data

Memory stores three basic categories of items:

• The operating system and other system software

• Application programs

• Data being processed and the resulting information

Memory size is measured in

kilobytes (KB or K), megabytes (MB), gigabytes (GB), or terabytes (TB)

System unit contains two types of memory

Volatile memory and non volatile memory

Volatile memory

Loses its contents when power is turned off ex. RAM

Nonvolatile memory

Does not lose contents when power is removed ex. ROM, flash memory and CMOS

Three basic types of RAM chips

• Dynamic RAM (DRAM)

• Static RAM (SRAM)

• Magnetoresistive RAM (MRAM)

Dynamic RAM

is a type of random-access memory that stores each bit of data in a separate capacitor within an integrated circuit. The capacitor can be either charged or discharged

Static RAM has

has three different states. It can be in: standby (circuit is idle), reading (the data has been requested) and writing (updating the contents)

Dynamic RAM has different types of DRAM

• SDRAM (Single Data rate RAM)

• DDR SDRAM (Double Data Rate Synchronous Dynamic RAM)

• DDR2 SDRAM

• DDR3 SDRAM

DDR2 SDRAM specs

8.5 GT/s; dual channel mode; memory installed in pairs

DDR3 SDRAM specs

Operates at lower voltages; consuming less power

12.8 GT/s; dual and triple channel modes

RAM chips usually reside

on a memory module and inserted into memory slots

Memory cache

speeds the processes of the computer because it stores frequently used instructions and data

ROM refers to

Memory chips storing permanent data and instructions

Firmware

provides instructions to help hardware start up, communicate with other devices, and perform basic input/output tasks.

Flash memory

can be erased electronically and rewritten

CMOS technology provides

high speeds and consumes little power

Hard disk drive

is a non-volatile storage device which stores digitally encoded data on rapidly rotating platters with magnetic surfaces

Drive

refers to a device distinct from its medium.

DVD

• "Digital Versatile Disc" or "Digital Video Disc,"

• is an optical disc storage media format

• video and data storage.

• DVDs are of the same dimensions as compact discs (CDs) but store more than six times as much data.

Blu-ray Disc

• is an optical disc storage medium to supersede the standard DVD format.

• storing PlayStation 3 games, highdefinition video and data storage with up to 50GB per disc.

• The disc has the same physical dimensions as standard DVDs and CDs.

USB flash drive

• consists of a NAND-type flash memory data storage device integrated with a USB (Universal Serial Bus) interface.

• USB flash drives are typically removable and rewritable

• USB flash drives weigh less than an ounce (30 g)

memory card or flash memory card

• solid-state electronic flash memory data storage device capable of storing digital contents

• digital cameras, handheld and Mobile computers, mobile phones, music players, digital cinematography cameras, video game consoles, and other electronics.

• high re-record-ability, power-free storage, small form factor, and rugged environmental specifications.

keyboard

used to type data into the computer

move some object on the screen and can do some action.

pointing devices

joysticks or game controllers

Other pointing devices mainly used for gaming

scanner

allows you to scan documents, pictures or graphics and view them on the computer. It converts image into dots that the computer can understand.

Digital cameras

are used to take electronic pictures of an object.

Microphones

are used to put sound into a computer. Today, commands can also be given to computer using your voice.

Monitors

shows the processed information on screen. It displays soft copy of the information.. When the device is turned off the information goes away.

Printers

produces a hard copy of the information. The information is printed on paper and can be used when the device is off.

Speakers

are used to output sound

Hardware

Physical, tangible parts of the computer system can be classified as

• Input devices

• Output devices

• Processing devices

• Storage devices

Processing devices

Components responsible for the processing of information within the computer system

Storage devices

components which allow data to be stored within a computer system

Bit

Can only have a value of either 0 or 1

Byte

8 bits (also known as a character)

ASCII

• code that assigns characters such as ‘a’, ‘b’, etc unique 8-bit values. This allows information created on one computer to be understood by other computers

• Most common

Kilobyte

1,024 bites

Megabyte

Roughly one million bytes

Gigabyte

One billion bytes

Terabyte

One trillion bytes

Radix or base

total number of unique symbols available in that system

The largest valued symbol always has a

magnitude of one less than the radix

decimal notation

writing of numbers in base-ten numeral system

decimal separator

indicates the start of a fractional part and with plus or minus symbol to indicate sign

binary system has a base or radix of

2

binary numbers are composed of two symbols

0 and 1

octal base or radix

8

hexadecimal base/radix

16

binary base/radix

2