Keyboard :: Input-output devices


  As is well known, while the keyboard is the primary input device into the computer. The technical aspect of this device is a set of mechanical sensors, pressure receiving the keys and closing one way or another specific circuit.
  I must say that the evolution of keyboards for IBM PC was not short-lived. First used the 83 -key keyboard, and then appeared with the AT - 84 's Key.   Most modern IBM PC compatible use extended keyboard.
  Major improvements over AT keyboard concerns the total ( 101 and up ) and the location of the keys. Location is the most standard QWERTY: about 60 keys with letters, numbers, punctuation marks and other symbols, and about 40 function keys.
  Device keypads. Currently, the most common two types of keyboards : mechanical and membrane switches. In the first case, the probe is a traditional mechanism with contacts from a special alloy. Despite the fact that this technology has been used for several decades, manufacturers are constantly working on its modification and improvement. It is worth noting that in keyboards known firms plated switch contacts, which significantly improves the electrical conductivity.
  Technology based on membrane switches, considered to be more progressive, though not give any advantages.