![]() The Perkins Brailler, first manufactured in 1951, uses a 6-key chord keyboard (plus a spacebar) to produce braille output, and has been very successful as a mass market affordable product. In 1892, Frank Haven Hall, superintendent of the Illinois Institute for the Education of the Blind, created the Hall Braille Writer, which was like a typewriter with 6 keys, one for each dot in a braille cell. When Louis Braille invented it, it was produced with a needle holing successively all needed points in a cardboard sheet. ![]() īraille (a writing system for the blind) uses either 6 or 8 tactile 'points' from which all letters and numbers are formed. But telegraph operators were already using typewriters with QWERTY keyboards to "copy" received messages, and at the time it made more sense to build a typewriter that could generate the codes automatically, rather than making them learn to use a new input device. #Keylord gloves codeThe code is optimized for speed and low wear: chords were chosen so that the most common characters used the simplest chords. In 1874, the five-bit Baudot telegraph code and a matching 5-key chord keyboard was designed to be used with the operator forming the codes manually. #Keylord gloves softwareThe output of the stenotype was originally a phonetic code that had to be transcribed later (usually by the same operator who produced the original output), rather than arbitrary text-automatic conversion software is now commonplace. The first widespread use of a chord keyboard was in the stenotype machine used by court reporters, which was invented in 1868 and is still in use. It was designed to be used by untrained operators (who would determine which keys to press by looking at the grid), and was not used where trained telegraph operators were available. The earliest known chord keyboard was part of the "five-needle" telegraph operator station, designed by Wheatstone and Cooke in 1836, in which any two of the five needles could point left or right to indicate letters on a grid. #Keylord gloves professionalHowever, stenographers typically train for three years before reaching professional levels of speed and accuracy. Many stenotype users can reach 300 words per minute. Currently stenotype machines hold the record for fastest word entry. Thad Starner from Georgia Institute of Technology and others published numerous studies showing that two-handed chorded text entry was faster and yielded fewer errors than on a QWERTY keyboard. #Keylord gloves portableThese portable devices first became popular with the wearable computer movement in the 1980s. Practical devices generally use simpler chords for common characters ( e.g., Baudot), or may have ways to make it easier to remember the chords ( e.g., Microwriter ), but the same principles apply. ![]() Due to the small number of keys required, chording is easily adapted from a desktop to mobile environment. Since Engelbart introduced the keyset, several different designs have been developed based on similar concepts.Īs a crude example, each finger might control one key which corresponds to one bit in a byte, so that using seven keys and seven fingers, one could enter any character in the ASCII set-if the user could remember the binary codes. Unlike pressing a chord on a piano, the chord is recognized only after all the keys or mouse buttons are released. If the user pressed keys 1 and 2 simultaneously, and then released the keys, 1 and 2 would be added to 3, and since C is the 3rd letter of the alphabet, and the letter "c" appeared. The keys were mapped as follows: a = 1, b = 2, c = 3, d = 4, and so on. In Engelbart's original mapping, he used five keys: 1, 2, 4, 8, 16. By pressing two or more keys together the user can generate many combinations. An ergonomic chorded keyboard without the board is known as a keyer.Įach key is mapped to a number and then can be mapped to a corresponding letter or command. ![]()
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