1. Representıng data

HOW COMPUTERS REPRESENT DATA? Bit : Binary Digit (0 or 1) (True or False) Bit Patterns are used to represent information. Numbers Text characters Images Sound And others

BIT / BYTE 8 Bits = 1 Byte

HOW COMPUTERS REPRESENT DATA? Using two symbols all numbers can be represented on a calculator as well as performing arithmetic operations A calculator translates the touch on the numeric keypad into series of 0s and 1s Each number then is looked at as a component of its positional values (each a power of 2) 19 will be represented as 00010011 0 0 0 1 0 0 1 1 19 128 64 32 16 8 4 2 1

Ascıı table

storage data unıts b = bit B = byte

BIG DATA

2. System unıt

System unıt Case that contains the major hardware components of a computer All-in-one

System-Unit Components Motherboard CPU Power Supply Cooling fans Internal Speaker Drive bays Expansion slots

System-Unit Components

Motherboard A motherboard (mainboard) is the main printed circuit board (PCB) found in computers and other expandable systems. It holds and allows communication between many of the crucial electronic components of a system, such as the central processing unit (CPU) and memory, and provides connectors for other peripherals. Motherboard specifically refers to a PCB with expansion capability and as the name suggests, this board is often referred to as the "mother" of all components attached to it, which often include sound cards,  video cards,  network cards,  hard drives, other forms of persistent storage;  TV tuner cards, cards providing extra USB or FireWire slots and a variety of other custom components

Motherboard

Which one is not located on the motherboard? Hard drive Memory. Sound card. Power supply.

Central processing unit (CPU) The CPU: The Real Computer CPU (microprocessor) Interprets and executes the instructions in each program Supervises arithmetic and logical data manipulations Heat-sink : A heat-dissipating component that drains heat from the chip

CPU – Instruction set Performs basic operations: Add Subtract Comparison Retrieve character from memory A program for Intel CPU does not work on Motorola CPU

CPU Control unit one of the two main parts Retrieves instructions from memory Interprets and performs those instructions Manages the machine cycle or processing cycle, the four-part process performed by the CPU Arithmetic logic unit (ALU) one of the two main parts Performs arithmetic and logical operations Involve adding, subtracting, multiplying, dividing Logical operations involve comparisons between two or more data items.

Machine cycle Instruction Cycle Fetch: Retrieves program instructions Decode: Determines what the program is telling the computer to do Execution Cycle Execute: Performs the requested action Store: Stores the results to an internal register Registers - store data when it must be temporarily stored in the CPU

Machine cycle Control Unit Arithmetic Logic Unit 3. EXECUTE Cache Registers Input/Output Mngmt Cache 3. EXECUTE Memory 2. DECODE 4. STORE 1. FETCH

The Machine Cycle

The Machine Cycle Today’s computers can go through this four-step process billions of times per second CPU speed is linked to this measure

What’s on the Motherboard? * 07/16/96 What’s on the Motherboard? Factors that affect the performance of a CPU include: Number of existing transistors Data bus width and word size Clock speed Operations per microprocessor cycle Use of parallel processing Type of chip *

What’s on the Motherboard? * 07/16/96 What’s on the Motherboard? Data bus Group of parallel wires that act as an electronic highway on which data travels between computer components Width measured in bits Pathway for the electronic impulses that form bytes Word Size Maximum number of bits the CPU can process at once is called the word size Nowadays, it 32-bits or 64-bits (Windows 7 is a 64-bit operating system) *

What’s on the Motherboard? * 07/16/96 What’s on the Motherboard? Clock Speed Events happen at a pace controlled by a tiny drummer: system clock System clock is an electronic circuit that produces rapid pulses and coordinates the computer’s internal activities. Each pulse initiates an operation. Clock speed indicates the number of pulses that system clock sends. For example, a CPU with a clock speed of 3 GHz performs 3 billion machine cycles per second. *

What’s on the Motherboard? * 07/16/96 What’s on the Motherboard? Parallel processing Method where more than one processor performs at the same time—faster processing *

What’s on the Motherboard? * 07/16/96 What’s on the Motherboard? Multi-core processing Access time reduced Processing time improved Each core handles incoming streams of data or instructions at the same time Two basic types: Dual core Quad core *

Evolution of Intel Microprocessors

What’s on the Motherboard? * 07/16/96 What’s on the Motherboard? Chipset Set of chips that supply the switching circuitry the CPU requires to move data throughout the computer The CPU and the input/output (I/O) bus linked through the chipset Provides a means to communicate with input and output devices *

What’s on the Motherboard? * 07/16/96 What’s on the Motherboard? Memory Chips on the motherboard or within the CPU that retain instructions and data Random access memory (RAM) Temporarily stores data and instructions for the CPU Volatile—contents erased after computer is shut off Allows CPU to access or store data and instructions quickly through RAM’s memory address feature Identifies and locates stored data *

What’s on the Motherboard? * 07/16/96 What’s on the Motherboard? *

What’s on the Motherboard? * 07/16/96 What’s on the Motherboard? Memory footprint Amount of RAM the operating system uses while it operates Virtual memory Section of the hard drive set aside to use when RAM gets full Access is much slower than accessing to RAM *

What’s on the Motherboard? * 07/16/96 What’s on the Motherboard? Cache memory Small unit of ultrafast memory built into or near the processor Used to store frequently or recently access program instructions or data Faster but more expensive than RAM Faster computers have more cache memory *

Data Storage Locations * 07/16/96 Data Storage Locations Virtual Memory Slowest, least expensive 0.013 seconds Fastest, most expensive *

Operating systems occupy a certain amount of RAM Computer Performance Computers with faster and larger cache memory and RAM have better performance Operating systems occupy a certain amount of RAM The speed of data from CPU to other circuits on the motherboard are also critical in the computer performance

What’s on the Motherboard? * 07/16/96 What’s on the Motherboard? Read-only memory (ROM) Contains prerecorded instructions to start the computer Nonvolatile—contents stored when CPU power off Basic input/output system (BIOS) First code run when the system is powered on Complementary metal-oxide semiconductor (CMOS) Starts the power-on self-test and verifies other system components are operating correctly Power-on self-test (POST) Checks circuitry and RAM, marking defective locations *

What’s on the Outside of the Box? * 07/16/96 What’s on the Outside of the Box? Front panel Power switch Used to turn the computer on Drive activity light Advises the user that the hard drive is retrieving data Power-on light Shows whether the power is on *

What’s on the Outside of the Box? * 07/16/96 What’s on the Outside of the Box? Outside a system unit Connector—physical receptacle used to plug a peripheral device into the computer Example: telephone jack Port—electronically defined pathway used to send data into and retrieve data from the computer Example: USB port *

What’s on the Outside of the Box? * 07/16/96 What’s on the Outside of the Box? *

What’s on the Outside of the Box? * 07/16/96 What’s on the Outside of the Box? Connectors on a notebook may vary This is Figure 2.29. *

What’s on the Outside of the Box? * 07/16/96 What’s on the Outside of the Box? USB (universal serial bus) ports Connects up to 127 peripheral devices Connects a variety of devices to the computer, including: Keyboards, Mice, Printers, Digital cameras Allows PnP (Plug and Play) *

What’s on the Outside of the Box? * 07/16/96 What’s on the Outside of the Box? USB hub Device that plugs into existing USB port Contains four or more additional ports This is Figure 2.20. *

What’s on the Outside of the Box? * 07/16/96 What’s on the Outside of the Box? FireWire (1394 ports) Created by Apple in 1995 Offers high-speed connections for dozens of peripheral devices (up to 63) Initially was much faster than USB Data transfer rates of FireWire FireWire 400—400 Mbps FireWire 800—800 Mbps FireWire S3200—next generation (expected to transfer data at 3.2 Gbps) This is Figure 2.20. *

What’s on the Outside of the Box? * 07/16/96 What’s on the Outside of the Box? Video connectors VGA (video graphics array) 15-pin male connector—works with standard monitor cables Transmits analog video signals Used for legacy cathode ray (CRT) monitors DVI (Digital visual Interface) port—lets LCD monitors use digital signals HDMI (High Definition Multimedia Interface) – higher transfer rate than DVI, can also transmit sound. This is Figure 2.20. *

What’s on the Outside of the Box? * 07/16/96 What’s on the Outside of the Box? Additional connectors Telephone Network PC card slot PC card ExpressCard Sound card Game card TV/sound capture board *