COE1161: ICT SKILLS

1. COE1161 FIRST YEAR 2017/2018 School of Engineering (SoE) COE1161: ICT SKILLS

2. COE1161 TODAY'S LECTURE • BLOCK STRUCTURE OF COMPUTERS AND FUNCTION OF COMPONENTS • INPUT AND OUTPUT DEVICES

3. COE1161 WHAT IS INPUT? • Input is any data or instructions provided to the computer by a person, the environment, or another computer. People have a variety of options available to input data and instructions into a computer. • Inputdata is a collection of unprocessed text, words and symbols; numbers; pictures; audio signals from a microphone; signals from another computer; temperature, speed, pressures and video. Once data is in memory, the computer interprets and executes instructions to process the data into information. • Instructions are the steps that tell the computer how to perform a particular task. Instructions entered into the computer can be in the form of programs, commands and user responses.

4. COE1161 Cont' • A program is a series of instructions that tells the computer what to do and how to do it. When a programmer writes a program, he or she inputs the program into the computer by using a keyboard, mouse or other input device. • Programs respond to commands that a user issues. • A command is an instruction that causes a program to perform a specific action. • A userresponse is an instruction a user issues by replying to a question displayed by a program. A response to the question instructs the program to perform certain actions.

5. COE1161 NOW WHAT ARE INPUT DEVICES? • Input devices accept data and instructions from the user or from another computer system. • An inputdevice is any hardware component that allows users to enter data or instructions (programs, commands, and user response) into a computer. • Depending on the application and your particular requirements, the input devices selected may vary. Popular input devices include the keyboard, mouse, scanner, microphone and digital camera. Storage devices such as disk drives serve as both input and output devices.

6. COE1161 1. KEYBOARD • A computerkeyboard is an input device that contains alpha-numeric keys you press to enter data into the computer. Desktop computer keyboards typically have from 101 to 105keys. • Computer keyboard are similar to electric typewriter keyboard that contain additional keys. • The keys on computer keyboards are often classified as follows: • Alphanumeric keys: letters of alphabet and numbers. • Numeric keypad. • Special keys: function keys, modifier keys and Cursor-movement keys

7. COE1161 Cont' • Most keyboards use the QWERTY layout, named for the first six keys in the top row of letters. The • QWERTY keyboard was designed 1800s for mechanical typewriters and was actually designed to slow typists down to avoid jamming keys. • Another keyboard most used is AZERTY, most French people use this kind of keyboard.

8. COE1161 Cont' • Most of today’s desktop computer keyboards are enhancedkeyboards. An enhanced keyboard has twelve function keys along the top, two CTRL keys, two ALT keys, and a set of arrow and additional keys between the typing area and the numeric keypad. • Desktop computers keyboard often attach via a cable to a serial port, a keyboard port, or a USB port on the system unity. Some keyboard; however, do not use wires at all.

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10. COE1161 Cont' • A cordless keyboard is a battery-powered device that transmits data using wireless technology, such as radio waves or infrared light waves. Cordless keyboards communicate with a receiver attached to a port on the system unit. • Long periods of standard keyboards use can cause injuries (repetitive strain injury -RSI) of wrists. Ergonomics keyboards attempt to reduce or eliminate this problem with designs that provide users with more natural comfortable hand wrist and arm position. You also can avoid injuries by adopting correct keyboarding practices

11. COE1161 Ergonomic style Cont'

12. COE1161 2. Pointing device • A pointing device is used to position a pointer on the screen. The pointer can have a number of shapes but is most often an arrow.

13. COE1161 2.1 MOUSE • A mouse is a pointing device that fits comfortably under the palm of your hand. The mouse is the most widely used pointing device on desktop computers. It is a small handheld device used to control the movement of a graphical pointer on the screen, often called a mouse pointer in this case. The mouse can be used to issue commands, draw, and perform other types of input tasks.

14. COE1161 Cont' • The top and sides of a mouse have one to four buttons, which have different functions depending on what program is running; some also have small wheel called scroll wheel for scrolling through long documents. The bottom of mouse is flat and contains a mechanism that detects movement of the mouse.

15. COE1161 TYPES OF MICES • Mechanical mouse: It has a rubber or metal ball on its underside that can roll in all directions. Mechanical sensors within the mouse detect the direction and the distance the ball is rolling and move the screen pointer accordingly. • You should place a mechanical mouse on a mouse pad, which is a rectangular rubber of foam pad that provides better traction than the top of a desk.

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17. COE1161 Cont' • Optical mouse: It has no moving mechanical parts inside. Instead, an optical mouse uses device that emit and sense light to detect mouse’s movement. Some uses optical sensors and others laser. You can place an optical mouse that uses optical sensors on nearly all types of surfaces, eliminating the need for mouse pad. An optical mouse that uses a laser usually requires special mouse pad. • An optical mouse is more precise than a mechanical mouse and does not require cleaning as does a mechanical mouse, but it is also more expensive.

18. COE1161 Cont' : Optical sensor

19. COE1161 Cont' • Cordless mice aren’t physically connected at all. They are battery-powered devices that transmit data using wireless technology, such as radio waves or infrared light waves. The wireless technology used for a cordless mouse is very similar to that of cordless keyboard discussed earlier.

20. COE1161 Mouse Techniques • Using the mouse involves five techniques: • 1. Pointing; Move the mouse to move the on-screen pointer. • 2.Clicking; Press and release the left mouse button once. • 3. Double-clicking; Press and release the left mouse button twice. • 4. Dragging; Hold down the left mouse button as you move the pointer. • 5. Right-clicking; Press and release the right mouse button.

21. COE1161 Many styles of trackball are available. Variants of the Mouse • Trackballs: A trackball is like a mouse turned upside-down. • The thumb is used to move the exposed ball and fingers to press the buttons.

22. COE1161 Cont' • Trackpads: A trackpad is a touch-sensitive pad that provides the same functionality as a mouse. • To use a trackpad, you glide your finger across its surface. • Trackpads provide a set of buttons that function like mouse buttons.

23. COE1161 Cont' • Integrated Pointing Devices: An integrated pointing device is a small joystick built into the keyboard. • To use an integrated pointing device, you move the joystick. • These devices provide a set of buttons that function like mouse buttons

24. COE1161 2.2 Light Pen • A light pen is a handheld input device that can detect the presence of light. Some light pens require a specially designed monitor, while others work with standard monitor. • With a pen-based system, you use an electronic pen to write on the screen and choose commands. To select objects on the screen, a user presses the light pen against the surface of the screen and then presses a button on the pen. Using a light pen is more direct and precise than using a mouse. • Pens are common input devices for handheld computers, like “personal digital assistants (PDAs).” • Pens are handy for making notes or selecting commands, not for inputting a lot of text.

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26. COE1161 2.3 Touch Screens • Touch-screen systems accept input directly through the monitor. • Touch screens use sensors to detect the touch of a finger. They are useful where environmental conditions prohibit the use of a keyboard or mouse. • Touch-screen systems are useful for selecting options from menus.

27. COE1161 2.4 Game Controllers • The two primary types of game controllers are joysticks and game pads. • Game pads usually provide controls for each hand. • Joysticks are popular for flight simulator and driving games.

28. COE1161 Audio-Visual (Multimedia) Input Devices • 3.1 Microphones and Speech Recognition • VoiceInput is the process of entering data by speaking into a microphone. Microphones can accept auditory input. The microphone may be a stand-alone peripheral that sits on top of a desk, or is built into the computer or device, or is in headset. Some external microphones have a cable that attaches to a port on the sound card on the computer. A microphone requires a sound card in the PC. • A sound card can digitize analog sound signals, and convert digital sound signals to analog form. • Voicerecognition also called speech recognition, is the computer’s capability of distinguishing spoken words. Voice recognition programs do not understand speech. They recognize a vocabulary of preprogrammed words. The vocabulary of voice recognition programs can range from 2 words to millions of words. • With speech recognition software, you can use your microphone to dictate text, navigate programs, and choose commands.

29. COE1161 Analog Sound Signals Digital Audio Output [electrical signals] (ex. 11100011) to computer Analog Signals are Digitized Cont'

30. COE1161 3.2 Video Input • Video input is the process of capturing full motion images into a computer and storing them on a storage medium such as a hard disk. • Some video devices use analog video signals. Computers, by contrast, use digital signals. To input video from these analog devices, the analog signal must be converted to a digital signal. To do this, plug a videocamera or other analog video device into a video capture port on the system unit.

31. COE1161 PC video camera • A PC video camera is a type of digital video camera that digitizes full-motion images. Digital cameras enables a user to capture still images, send email messages with video attachment, add live images to instant messages and make video telephone calls. During the video telephone call, both parties see each other as they talk over the Internet. • Video images may be compressed to use less memory and storage space

32. COE1161 Web cams • Aweb cam is a video camera that displays its output on a Web Page.

33. COE1161 4. OPTCAL INPUT DEVICES • 4.1 Bar Code Readers • Bar code readers can read bar codes - patterns of printed bars. • The reader emits light, which reflects off the bar code and into a detector in the reader. The detector translates the code into numbers. • Flatbed bar code readers are commonly found in supermarkets. Courier services often use handheld readers.

34. COE1161 Bar code readers commonlytracksales inretail stores Cont'

35. COE1161 4.2 Image Scanners and OCR • Image scanners digitize printed images for storage and manipulation in a computer. • A scanner shines light onto the image and interprets the reflection. • Optical character recognition (OCR)software translates scanned text into editable electronic documents. • There was time when the only way to transfer an existing document (source document) into the computer was to retype it. Now, however, devices such as optical scanners can capture data directly from a source document. • An opticalscanner, usually called a scanner, is a light-sensing input device that reads printed text and graphics and then translates the results into a form the computer can process.

36. COE1161 TYPES OF SCANNERS • 1.Flatbed Scanner: is similar to a copy machine. The scanning mechanism passes under the item to be scanned, which is placed on a glass surface. • Scannable items: single sheet documents, bound material, photograph, some models include trays for slides, transparencies, and negatives.

37. COE1161 Cont' • 2.Pen or Handheld Scanner: moves a pen over text to be scanned, and then transfer data to computer. It is ideal for mobile users, students and researchers. • Scannable item: any printed text.

38. COE1161 Cont' • 3.Sheet-fed Scanner: Item to be scanned is pulled into a stationary scanning mechanism. It is smaller than a flatbed scanner and some models designed specifically for photographs are called photo scanner. • Scannable items: single sheet documents, photographs, slides (with an adapter) and negatives.

39. COE1161 Cont' • 4.Drum Scanner: item to be scanned rotates around stationary scanning mechanism. It is very expensive and is used in publishing industry. • Scannable items: single sheet documents, photographs, slides and negatives.

40. COE1161 OUTPUT DEVICES • What is output? • Output is the result produced by a computer i.e. data that has been processed into a useful form. • A computer generates several types of output, depending on the hardware and software being used and requirements of the user. Users view output on a screen, print it, or hear it through speakers or headsets. While working with a computer, a user encounters four basic categories of output: text, graphics, audio and video.

41. COE1161 Cont' • Text: Examples of text-based documents are memorandums, letters, reports, announcements, press releases, advertisements, newsletters, envelopes, and mailing labels. • On the web, users view and print many other types of text-based documents. These include newspapers, magazines, books, famous speeches, and historical lectures.

42. COE1161 Cont' • Graphics: Documents often include graphics to enhance their visual appeal and convey information. Business letters have logos. Reports include charts. Newsletters use drawings, clip art, and photographs. Users print high-quality photographs taken with digital camera, eliminating the need for film or film developers. Many Web sites use animated graphics, such as blinking icons, scrolling messages, or simulations.

43. COE1161 Cont' • Audio: Users insert their favorite music CD in a CD or DVD drive and listen to the music while working on the computer. Software programs such as games, encyclopedia, and simulations often have musical accompaniments for entertainment and audio clips, such as narration and speeches, to enhance understanding. • On the web users turn into radio and television stations and listen to audio clips or live broadcasts of interviews, talk shows, sporting events, news, music, and concerts. They also use Internet to have real time-time conversations with friends, coworkers, or family members, just as if they were speaking on the telephone.

44. COE1161 Cont' Video:as with audio, software and web sites often include video clips to enhance understanding. Users watch a live or prerecorded news report, view a movie, see a doctor perform a life-saving surgery, enjoy a live performance of their favorite jazz band on the computer. Attaching a video camera to the computer allows users to watch home movies on the computer. They can also attach a television’s antenna or cable to the computer and watch a television program on the computer screen.

45. COE1161 OUTPUT DEVICES • Output devices return processed data back to the user or to another computer system. An output device is any hardware component that displays, prints, or transmits the results of processing. It conveys information to one or more people. Commonly used output devices are: display devices, printers, speakers, headsets and so on.

46. COE1161 1. Display devices – Monitor/ Screen/ VDU (video display unit) • A display device, or simply display is an output device that visually conveys text, graphics and video information. Information on a display device, sometimes-called softy copy exists electronically and displays for a temporally period. • Display devices consist of a screen and the components that produce the information on the screen. • Desktop computers typically use monitor as their display device. A monitor is a plastic or metal that houses a display device.

47. COE1161 Types of monitors • Monitors are categorized by the technology they use: • Cathode ray tube (CRT) monitors • Flat-panel displays also called LCD monitor.

48. COE1161 Cont' • And by the way they display colors: • Monochrome – One color on a black background • Grayscale – Shades of gray on a white or off-white background • Color – From 16 to 16 million unique colors

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50. COE1161 Cont' • CRT Monitors In CRT monitors, electrons are fired at phosphor dots on the screen. The dots are grouped into pixels, which glow when struck by electrons. In color CRTs, each pixel contains a red, green, and blue dot. These glow at varying intensities to produce color images. • Flat-Panel Monitors Most flat-panel monitors use liquid crystal display (LCD) technology. Passive matrix LCD uses a transistor for each row and column of pixels. Active matrix LCD uses a transistor for each pixel on the screen. Thin-film transistor displays use multiple transistors for each pixel.