Hardware & Input/Output

Transcription

1 Hardware & Input/Output CIT 100 Norm Downey Why Binary? Binary is a numbering system that uses only two digits 0 s and 1 s Electricity within a computer s circuitry can only be in one of two states: On Off Binary can be used to represent the two states of an electrical circuit 1 for on 0 for off 3 Counting in Binary Decimal Binary

2 Units of Measure Prefix Abbreviation Amount Kilo K 1000 (thousand) Mega M 1,000,000 (million) Giga G 1,000,000,000 (billion) Tera T 1,000,000,000,000 (trillion) Binary and Digital Digital devices store the data in a binary format Binary data is measured in two common ways bits Bytes All are abbreviated using single a CAPITAL letter 5 6 bits bit short for binary Digit One bit can either a 1 or 0 Data transfer rates are measured in bits per second (bps) Kbps Kilo (thousand) bits per second Mbps Mega (million) bits per second Bytes Memory (or storage) size is measured in Bytes One Byte = 8 bits One Byte = one printed character Note lower case b for bits 7 8 2

3 Bytes One Byte represents a value from 0 to 255 Commonly used to represent data storage KB KiloBytes ~ Thousand Bytes (1024 bytes) MB MegaBytes ~ Million Bytes (Floppy disks) GB GigaBytes ~ Billion Bytes (Flash drives) TB TeraBytes ~ Trillion Bytes (Hard disks) Note capital B for Byte. bits & Bytes bits are used to measure data transfer speeds Example: the speed of your Internet connection in bits might be 8 Mbps (8 mega bits per second) bits = small b Bytes are used data storage or memory capacity Example: the amount of RAM installed on your PC might be 6 GB (6 giga Bytes) Bytes = capital B 9 10 Hardware Integrated Circuits and Moore s Law Integrated Circuits A small, wafer thin chip, usually made of silicon, that can function as an amplifier, timer, microprocessor, or even computer memory Can contain millions of transistors, resistors, and capacitors Can perform calculations and store data digitally Moore s Law A 1965 observation made by Gordon Moore, co-founder of microprocessor maker Intel, that the number of transistors that can be placed on an integrated circuit doubles roughly every 2 years

4 Mother Board A printed circuit board that contains: The Central Processing Unit (CPU), Support chips (integrated circuits), Random Access Memory and Expansion slots Central Processing Unit (CPU) Brains of the computer - where most calculations take place In terms of computing power, the CPU is the most important element of a computer system CPU is a microprocessor Multi-core technology refers to housing more than one CPU on a chip Central Processing Unit (CPU) Instruction Cycle 15 CPU size compared to coins Heat Sink Part of a computer s cooling system, mounted above the CPU and composed of metal or ceramic fins or blades designed to draw heat away from the processor 16 4

5 Cache Memory Cache Memory chips sit physically closer to the CPU for faster access Faster than RAM More expensive than RAM Internal PC Components 17 CPU L1 Cache L2 Cache RAM Memory 18 Data Bus Internal bus Sometimes called the Front-Side-Bus, connects the CPU, memory, hard drive and other internal components of the computer via pathways on the motherboard External Bus Electronic pathways that connect external devices, such as a printer to the computer Universal Serial Bus is an example of an external bus

6 RAM Random Access Memory Fast, temporary memory, requiring electricity, that is used for holding data while computer is on Most computers have 4 GB or more 21 DIMM Dual Inline Memory Module Found in desktop computers SODIMM Small Outline Dual Inline Memory Module Found in notebook computers 22 Video RAM (VRAM) Used to store image data for a computer display in order to speed the processing and display of video images Video Ports VGA Video Graphic Array Used for external monitors HDMI High Definition Multimedia Interface Compact audio/video interface for transmitting uncompressed digital data Variant of USB Networking Ports RJ-11 Telephone Smaller than RJ-45 RJ-45 Network (Ethernet) Larger than RJ-11 Indicator light showing active network connection

7 Ports USB Universal Serial Bus Can connect up to 127 devices Used for mice, printers, phones, etc. Supplies small amount of power to charge or run device Supports hot swapping and plug & play Many types of connectors and variations Hot Swapping Types of Computers Ability to add and remove devices to a computer while the: Computer is on and Have the operating system automatically recognize the change (Plug and Play) Desktop Laptop/Notebook

8 Types of Computers Types of Computers Netbook Tablet Notebook Replacement Phablet Types of Computers Smart Phones Apollo Command Module Did I mention Embedded Computers? Computers found in ordinary devices such as gas pumps, supermarket checkouts, traffic lights and home appliances

9 Input/Output Defined Input Devices An input device assists in capturing and entering raw data into the computer system An output device allows you to observe the results of computer processing with one or more of your senses Input Devices - Keyboards Multifunction Keyboard Cabled vs. Wireless Keyboards Types of Keys Letters and Numbers Cursor movement ( ) Numeric keypad Toggle Keys (Caps Lock, Num Lock) Function Keys (F1, F2 ) Modifier Keys (Ctrl, Alt, Shift, Windows Key ( ))

10 Input Devices Pointers (Mice) Seven things you can do with a computer mouse: Point (includes roll-over) Click (left mouse button) Double-Click (left mouse button) Right click Click and drag (left mouse button) Right click and drag Triple click (left mouse button) Assumes mouse with no scroll wheel Scanners RFID Radio Frequency Identification Digital tag containing tiny antennae for sending/receiving and storing data Commonly used for inventory tracking, toll collection, WDW Magic Bands, and tracking pets QR Codes Digital code that when scanned acts as a pointer to website QR Code to Bing.com Output Devices Output Output enables the user to see, hear or feel the results of the processing operations Two main types of output: Visual Audible

11 Audible Output Visual Output Text Words and numbers printed and on screen Graphics Images printed and on screen Video You know what video is, right? On screen, often including audible component Visual Output Monitors LCD Liquid Crystal Display Found on most desktop and notebook computers LED Light Emitting Diode Electronic Component that emits light when an electrical current is passed through it OLED Organic Light Emitting Diode Extremely thin panels of organic molecules sandwiched between two electrodes AMOLED Active Matrix Organic Light Emitting Diodes Screen type found in mobile devices sharp display with wide view angles Visual Output Hardware - Printers Impact Some part of the printer hits or touches the page Line Printers Letter Quality Printers Dot Matrix You do NOT own one of these types of printers Non-Impact Only ink touches the page Inkjets You MIGHT own one of Laser Printers these types of printers

12 Visual Output Ink Jet Printers Spray ink onto paper Common household printers Cheap to buy (under $100) Expensive to run (that is, they are expensive to own because ink cartridges are generally expensive and ink jet printers use up lots of cartridges) Slow compared to laser printers Visual Output Laser Printers Works like a copier: A laser is used to create an electric charge on a rotating drum Toner is attracted to areas on drum that are charged Toner is then applied to paper from the drum Expensive to buy Cheap to run lots of prints per cartridge Faster than Ink Jets Color is still expensive Storage Computer Data Storage CIT 100 Norm Downey

13 Why is storage necessary? To store data when the PC is off. RAM memory is volatile and loses it contents when powered off, storage is non-volatile and does not lose it contents when powered off Data storage is cheaper than RAM memory easier to transport than RAM memory which requires a power source RAM vs. Storage RAM Storage Power required? Yes No Cost Expensive Cheap Speed Fast Slow Portable? Not really Yes Speed vs. Cost Faster Speed, More Expensive Memory vs. Storage Memory Device Cache Memory Access Speed Fastest Cost Per MB Highest RAM Fast High Hard Disk Medium Medium Storage CD ROM Slow Low Slower Speed, Less Expensive Back up Tape Very Slow Lowest

14 Storage Capacity Measurements Storage capacity is measured in Bytes Megabytes (MB Millions of Bytes) Gigabytes (GB Billions of Bytes) Terabytes (TB Trillions of Bytes) Read/Write vs. Read Only Read/write Can read from and write to media Example: hard disks Read Only Can read, but not write to media Example: CD-ROM disks Sequential vs. Random Access Magnetic Storage Media Sequential Access Access data in a specific order Slower, cheaper Example: magnetic tape Random Access Access data from anywhere on the media Faster, more expensive. Example: hard disks or USB Drive

15 Storage Technology: Magnetic Media (disk or tape) is coated with tiny magnetically sensitive particles Electromagnetic Read/Write Head Reading senses recorded magnetic pattern and converts them into electrical impulses Writing Rearranges magnetic particles into meaningful patterns Magnetic Storage Sectors, Tracks and Clusters Data Fragmentation

16 Virtual Memory Method of using a computer s hard disk as an extension of RAM When RAM is full, data is swapped back and forth from RAM to the hard drive Hard drives are slower than RAM to make any PC faster, get as much RAM as possible Virtual Memory hard disk swap file page swapped in most recently transferred data or program instructions Virtual memory management page swapped out memory least recently used data or program instructions Optical Storage Media Storage Technology: Optical Uses tightly focused laser to read microscopic surface of plastic disc Pits indentations that absorb laser light corresponds to a 0 Lands flat areas that reflect laser light corresponds to a 1 Remember that discussion about binary? CD s and DVD s

17 How does an optical disc work? CDs, DVDs & Blu-Ray Discs CDs have the biggest Pits and Lands and uses the laser than covers the most disc DVD s use smaller Pits and Lands than a CD and the laser is focused onto a smaller surface area and consequently can store about 6 times as much data as a CD Blu-Ray discs use even smaller Pits and Lands than a DVD with an even tighter focused laser allowing Blu-Ray discs to store about five times the data of a DVD disc CDs, DVDs & Blu Ray Discs Solid State Storage Devices CD Compact Disc Storage Capacity 670 MB DVD Digital Versatile (or Video) Disc Storage Capacity = 4.7 to 17 GB Blu Ray Disc Named for the blue color laser beam used to read discs Storage Capacity = 25 to 50 GB

18 Solid State Drives (SSDs) No moving mechanical components More resistant to physical shock than traditional hard drive Run silently Have lower access time (means they re faster than hard drives) Expensive While the price of SSDs is declining, they are still about 4 times more expensive than similar capacity hard drive Typically found in netbooks and notebook replacement computers USB Flash Drives Also called thumb drives, pen drives, key drives & memory sticks No moving parts Flash memory is small, light and fast Expensive compared to discs Other solid state storage devices PC Card used with notebook PCs For use in digital cameras Secure Digital cards Compact Flash cards Memory Sticks Solid State storage devices have no moving parts CLOUD STORAGE

19 Cloud Storage Cloud = Internet Allows user to access data from, and save data to, an off-site, Internet based storage system that is maintained by a third party instead of storing information locally Examples: Microsoft s One Drive Dropbox Google Drive Apple s icloud Advantages Access from anywhere No need for physical storage Fewer worries about losing data Data can be shared Disadvantages Cost might be subscription based Security of third party storage Requires Internet connection Limited in size Cloud Storage Computer Data Storage CIT 100 Norm Downey 75 19