csci 1200 julie benoit [email protected] introduction to computing
TRANSCRIPT
CSCI 1200
Julie Benoit
Introduction to Computing
Bit Strings Represent
• numbers.
• alphanumeric : ASCII / Unicode.
• instructions.
• other stuff : sound or image data for example.
Volume / Size / Capacity
• Kilobyte (K) – thousand bytes
• Megabyte (MB)– million bytes
• Gigabyte (GB) – billion bytes.
• Terabyte (TB) – trillion bytes.
• Petabye (PB) – quadrillion bytes.
Note : MB vs Mb
Volume / Size / Capacity
• 1 K : text on back of DVD case.
• 1 MB : 1.5 sec of DVD quality video.
• 1 GB : a little less than 30 minutes of DVD quality video.
• 1 TB : about 230 DVD movies.
• 1 PB : about 238,600 DVD movies.
CPU
• Central Processing Unit.
• converts input to output.
• carries out instructions.
• mathematical & logical operations.
• communicates with other devices.
CPU
• motherboard :– circuit board.– location of the CPU.
• Compatibility :– instruction sets
• Performance / Speed :– clock speed, GHz.
CPU Parts
• ALU – arithmetic logic unit.
• Bus – data travels in parallel.
• Cache & Registers – high speed, local memory.
Computer Speed
• Instruction set
• Word Size
• Access Speeds
• Specialized hardware
• Parallel processing
• Clustering multiple machines
• Memory
Memory
• main memory / RAM.
• CPU reads main memory.
• addressed cells (Random Access).
• info held using electrical current:– need for ROM, CMOS, Flash & secondary
memory.
Memory
ROM : read only memory, non-volatile.CMOS : low energy, battery powered
RAM, date & time.Flash : fast, only needs power to change,
portable devices.
Secondary memory : long term storage.
Memory
• main memory / RAM.
• CPU reads main memory.
• addressed cells (Random Access).
• info held using electrical current:– need for ROM, CMOS, Flash & secondary
memory.
Storage
• magnetic tapes
• magnetic disks (floppy disks)
• hard disks
• optical disks (CD, DVD, Blu Ray)
• solid state devices (memory sticks & cards, USB flash drives)
Input Devices
Keyboards :
• Qwerty / Dvorak / Alphabetic
• ergonomic
• compact
• membrane
• one handed
• folding
Input Devices
`~ 1! 2@ 3# 4% 5^ 6^ 7& 8* 9( 0) [\{ ]} \\|
'" ,< .> p y f g c r l /? +=
a o e u i d h t n s -_
;: q j k x b m w v z
Input Devices
Pointing Device :
• selecting from options / menus.
• spatial tasks / graphics applications.
• efficiency
Input Devices : Pointing
• Mouse : mechanical, light
• Touch Pad : finger pressure
• Track Ball : upside down mouse
• Pointing Stick : TrackPoint, Isopoint
• Joystick : and other gaming devices
• Tablet & Stylus
• Touch Screen
Input Devices : Reading
• Optical Mark Readers
• Bar Code Readers
• Magnetic Ink Character Readers
• RFID Tags & Readers
Input Devices : Reading
• Optical Character Recognition
• Handwriting recognition
• Smart Whiteboard
Input Devices : Digitizing
• Scanner
• Digital Camera
• Video Digitizer
• Digital Video Camera
Output : Monitor
• most familiar (VDT)
• diagonally in inches
• pixels, dpi, resolution
• colour depth : number of colours that can be displayed at one time
• video adaptor / video card
• VRAM
Output : Monitor
• Liquid Crystal Display
• Cathode Ray Tube
Output : Printers
• impact & non-impact
• dot matrix printers & line printers
• laser & ink jet
• resolution
• plotter
• multi-function devices.
Colours
• light & pigment are different
• Pigment : cyan, magenta, yellow & black
• Light : red, green, blue
Sound Output
• sound card – accept a microphone, play sound through speakers & headphones.
• all Macs & some PCs have on board sound.
• synthesized speech, music, & sounds.
Fax Machines / Fax Modems
• phone lines
• dots to create the image
Combined Devices
• some devices do both I/O.
• peripherals interface with the world.
Ports, Slots, Buses & Bays
• port : connect a device.
• Slot : place to insert a special piece of hardware.
• Bus : group of wires connecting bays, ports and slots to the CPU.
• Bay : open space in the box for a storage device.
Standard Ports
• serial port : one bit at a time, modem
• parallel Port : groups of bits, printer
• keyboard / mouse ports
USB ports
• faster, generic, multiple devices, various standards
Special Ports
• on expansion cards
• video port for the monitor
• microphone, speaker, MIDI for attaching sound equipment
• network card adds a port to connect to the LAN