Input, Process, Output

1. Input, Process, Output Supplemental Lecture Notes

2. Typical System • Computer case • Monitor • Printer • Speakers • Modem • Keyboard • Mouse

3. Computer Components • Power supply • Hard drive • Expansion card • Expansion slot • System board • CD-ROM or DVD-ROM • Floppy disk • Drive bay • Central Processing Unit (CPU) • Random access memory (RAM)

4. Power Plays • The capacity of a power supply is measured in watts • Computer uses 250; light bulb uses 60 • Can use • Surge protector • UPS

5. Ports • Ports are connectors at the back of a computer system that you use to plug in an external device. This allow instructions and data to flow between the computer and the device

6. Any Port in a Storm • Parallel port – 25 holes; female connector; LPT1; printer or storage devices • Monitor port • Keyboard port • Serial port – 9 or 25 pins; male connector; COM1; mouse or modem • Game port • Network port • USB port • 127 devices • Printer, modem, joy stick

7. Growing • An expansion card is a circuit board that lets you add new features to a computer • Video • Modem • Sound • Network Interface

8. Upgrades • Upgrading refers to replacing an old or obsolete component with a newer component to improve the efficiency of the computer • Upgrading also can include adding a new component like a tape drive or DVD to increase the capabilities of a computer • Increasing the amount of memory in a computer is one of the most effective upgrades you can perform

9. Input and Output Chapter 2

10. Mouse Actions • Click – selects • Right click – displays commands • Double click – opens • Drop and Drag – moves items on screen

11. Mice • Types • Conventional • Wheel mouse • Wireless mouse • Programmable mouse – e.g. three buttons • Optical sensor mouse • Other devices • Touchpad • Trackball • Pointing stick

12. Keyboards • There are 101 keys on a keyboard to help you input information • Function keys let you perform specific task • Can use CNTL-x shortcuts to execute commands • CNTL-C – copy • CNTL-X – cut • CNTL-V – paste • Windows key will quickly display the start menu

13. Printers • Speed of a printer is measured in pages per minute (PPM). A higher speed represents faster output • Resolution determines the quality of images • A higher resolution results in sharper images • Printer resolution is measured in dots per inch (dpi) • 600 dpi is acceptable; 1200 is better for images • Resolution expressed with two numbers represents dots per inch across and down

14. Types of Printers • Ink-jet: has a print head that sprays ink through tiny nozzles onto a page • 2 to 10 pages (ppm) • 360 to 2400 dots per inch • Color printers spray cyan, magenta, yellow and black to create different colors • Laser-printer • Works like a photo copier • Speed of 4 to 16 pages • Have a CPU • 600 to 2400 • Memory – 2mb to 8 Mb

15. Other Types • Dot matrix • Print head contains small blunt pins that strike an inked ribbon • Useful for multi-part forms • LED printer • Similar to lasers but cheaper • Color photo printer • Multifunction Printer

16. Print Buffer and Spoolers • Printer buffer: section of memory printer stores information waiting to print • Printer spooler: program on your computer that stores information waiting to print • Stores more information than the buffer • One spooler for each connected printer

17. Monitors • Video cards translate instructions from the computer into a form Most computes the monitor can understand • require at least 2 mb of video card memory • Accelerated Graphics Port (AGP) – uses AGP bus to communicate directly with main memory • 3D Graphics Accelerator has chip called a GPU optimized for 3-D graphics

18. Monitor Metrics • The smaller the dot pitch, the crisper the image • 0.28mm is acceptable • Refresh rate is measured in hertz (Hz) • Times per second computer redraws the image • 72 Hz or more is acceptable

19. Resolution • Amount of information a monitor can display • Measured by the number of horizontal and vertical pixels • Monitors switch settings based on the resolution and refresh rate of video card • Video card determines number of colors a monitor can display • 256 suitable for most home use • 24-bit displays more colors than eye can distinguish

20. Communications • Modems let a computer exchange information through telephone lines • Speed of a modem determines how fast it sends and receives messages • 56,000 bps (56 Kbps) • V.90 standard: receive 56K and send 33.6K • Speed at which information flows depend on the quality of the phone line • A modem needs a communications package to manage the transmission of information • Data compression – squeezes together data

21. High-speed Connections • ISDN – Integrated Services Digital Network • Digital phone line • 56 Kbps to 128 Kbps • Cable Modem • Same cable as TV • 4000 Kbps • DSL – Digital subscriber line • High speed digital phone line • 1000 – 6000 Kbps • Satellite

22. Sound Cards • Sampling Rate: at least 44.1 KHz • Full-duplex • Talk and listen at same time • Musical Instrument Digital Interface (MIDI) support • Wavetable synthesis • Actual recordings • FM synthesis • Imitated sounds

23. TV Tuner Cards • Require a video card to operate

24. Scanners • A scanner is a device that reads images and text into a computer • Most scanners come with Optical Character Recognition (OCR) software. This software places scanned text into a document that can be edited in a word processor • Color dept is measured in bits and indicates the number of colors a scanner can detect • 36 bit color depth is acceptable

25. Resolution • Resolution determines the amount of detail a scanner can detect • Ranges from 600 dpi to 2400 dpi • You usually don’t need to scan at a higher resolution than a printer can produce or a monitor can display • Most monitors are 73 dpi • Printers vary

26. Cameras • Resolution is measured in megapixels • 1000 x 1000 pixels • 1, 2 and 3 megapixel cameras are available • Digital video cameras use a Charged Coupling Device (CCD) to capture video • Quality depend on amount of detail a CCD can detect • Most CCD’s have resolution between 250,000 and 700,000 pixels • Web cameras – resolution and speed determine quality of image • Common transfer rates • 15 frames per second at 640 x 480 pixels • 30 frames per second at 352 x 288 (clearer but smaller)

27. MP3 • Sound format used to CD-quality music over the Internet • Compresses sound • Commonly 64 bit memory

28. USB and Firewire • High-speed ports that allow information to quickly transfer between a computer and an external device • USB • Supports up to 127 device • USB 1.0: 12 megabits per second • USB 2.0: 480 Mbps • FIREWIRE • 63 devices at 400 Mbps • Can purchase Firewire expansion card

29. Processing Chapter 3

30. CPU (Central Processing Unit) • Processes instructions, performs calculations, and manages the flow of information • Performance: • CPU speed is a major factor in determining how fast a computer operates (faster the speed, faster computer operates) • Measured in megahertz (MHz) A clock cycle relates to the clock that controls the timing in the microprocessor. • For example, a 900MHz (megahertz) clocked microprocessor generates 900 million clock cycles per second. • Each generation of CPU is more powerful than the one before. It's clock cycles are faster at a given speed

31. Processing • The Central Processing Unit (CPU) is the main chip in a computer • Processes instructions • Performs calculations • Manages the flow of information

32. Types of CPUs • Intel Pentium Processor • Speeds of 450 MHz to 1.13 GHz • Intel Celeron • Needs of home machines (500-700MHz) • AMD Athlon Processor • Business and home use • AMD Duron Processor • Home use • VIA Cyrix Processor • Inexpensive CPU

33. Processing • Random Access Memory – Temporarily stores data inside a computer • Constantly overwritten • Measured in megabytes (MB) • 64 minimum these days100 MHz (millions of cycles per second) • Dynamic RAM is type of memory chip that makes up memory in many computer systems. Access speed measured in megabits • Most system boards can support access speed of Single Inline Memory Module (SIMM) – 9 memory chips • Dual Inline Module (DIMM) – 18 memory chips • If you have limited memory or you have many programs open, your computer may need to use part of the hard drive to simulate more memory

34. Using Memory Cache • Look through documents on your desk (internal cache) • Look through documents in your desk drawer (external cache) • Looking through documents in your filing cabinet (RAM)

35. Using Memory Cache • Look through documents on your desk (internal cache) • Look through documents in your desk drawer (external cache) • Looking through documents in your filing cabinet (RAM)

36. Math Coprocessors • A special processing unit that assists the CPU in performing certain operations. • A math coprocessor is a chip or part of a chip that specializes in doing math. Hardware that attaches to the motherboard or is part of the CPU. • Extends the capabilities of a CPU in a transparent manner. • Performs mathematical computations, particularly floating-point operations. • Besides being able to add, subtract, multiply and divide floating-point numbers, they can also operate on them to perform comparisons, square roots, logarithms, sine, cosine, tangent, absolute value, and remainders • Also called numeric coprocessors or floating point units (FPU).