Switch Input
Less direct methods of inputting keystrokes and mouse clicks are slower and less effective than direct methods of pointing or keyboard input. Individuals who have very poor accuracy in targeting or very minimal movement use switches to input data into applications. There are two main methods of inputting data using a switch:
- Scanning:
- Morse Code:
Using this approach, a line of letters, mouse input and possibly even computer commands are displayed on screen. A coloured marker moves across the array of choices in linear or in a row/column pattern. The individual hits the switch when the marker is at the selection they want to input. Again, due to the slow rate of input, other strategies such as word prediction, are frequently used with this input method.
Although rarely used among the general public, inputting the Dits and Dahs or long and short signals of Morse Code continues to be a fairly efficient means of computer input for switch users. I have known Morse Code users with disabilities such as quadriplegia or muscular dystrophy who achieved input rates of 20 to 25 words per minute. If the user has good voice control, voice recognition can be a faster alternative, but for those without, or with limited funds, Morse code can give full text and mouse input for Macintosh and Windows or DOS operating systems. Morse can also be augmented with speech or word prediction.
Switches themselves can be purchased from a variety of sources. The interface which produces the scanning array or Morse Code translation to the system is usually a combination of software and hardware.
See the Resource page for this module for switches and interfaces for scanning and Morse Code.