Unit 2 - Input and Output Devices

Unit 2 - Input and Output Devices

1. Analogue and digital data

   • Computers process data by using 0's and 1's
   • Modern input devices use digital data but some systems are based on analogue systems and require converting.
     • e.g. light and heat sensors. An ADC (analogue to digital converter) will be used to convert data (into binary) in order for a computer to process the data

2. Devices

   • Video Camera
     • A device that can capture and store moving images. Found in television and film industry, often in homes too.
       • **Sound & video at the same time.**
       • **Locations and buildings can be monitored.**
       • **Edited easily.**
       • ***Digital video takes up a lot of computer storage space.***
       • ***Editing needs a computer with a fast processor and high performance graphics card.***
   • Webcam
     • attached to PC's, laptops and mobile phones to capture still and moving pictures. used for video conferencing and video messages
       • **Allows people to chat face-to-face from across the world for personal or business use.**
       • **Inexpensive to produce**
       • **Widely used in many devices**
       • ***Usually only designed for streaming video online and do not have internal storage.***
       • ***low power resolution than a standard digital camera.***
   • Light Pens
     • USed to draw and control elements directly onto the computer.
       • **Precise inputs can be made faster than a mouse or a keyboard.**
       • **Data can be 'written' onto the screen.**
       • ***Requires practice and a steady hand to use.***
       • ***Rarely used today due to the introduction of touchscreens.***
   • Keyboard
     • Input text, number, symbols and data. found in schools, offices and homes.
       • **function keys can be set to open specific programs.**
       • **wireless versions are now available**
       • ***only input data as fast as you can type***
   • Remote Control
     • Control what you want to watch/listen/see.
       • **each button has a different function**
       • **light, easy to use.**
       • ***battery operated***
       • ***easy to use***
   • Numeric Keypad
   • Joystick
   • Mouse
     • Used to navigate the screen and select/deselect items in a program.
       • **Easy to use**
   • Magnetic strip reader
   • Touchscreen
   • Touchpad
   • Scanner

3. Output devices

   • TFT Monitor
   • CRT Monitor
   • Projector
   • Inkjet Printer
   • Laser Printer
   • Dot Matrix Printer
   • Graphics Plotter