Chapter 02 - Hardware Input Devices

Chapter 02 - Hardware Input Devices

1. Main features of a touchscreen

   • Input and output device, covered by thin membrane which is sensitive to pressure, Or infared light along the edges, users finger pressure is dectected, X and Y cordinates calculated

2. Main features of speech input

   • A microphone attached to soundcard to capture speech, sound converted from analogue to digital using sampling, then compared to database of sound for matching patteren of frequencies/wavelengths
   • Advantages
     • No ICT skills required just spoken command, can be controlled from a distance, suitable for disabled, Deigned to respond only to certin users voices
   • Disadvantages
     • May be complicated to set up, may be activated by background noise, may not recognise voice if sick,

3. Sensor and actuator

   • Sensor records heat monitored at intervels. Microphones records the sound at intervels
   • Actuator attached to boiler or pump. The computer sends a signal to turn on and off

4. Benefits of digital tv

   • Improved quality and sound and can broadcast a higher resolution
   • Increase the number of tv channels, improved accessability for visually and hearing impaired
   • Access to interactive services giving more information about shows or to play games
   • Increased user control as different broadasts can be viewed on a single channel