Keyboard of computer

History

The first data-processing keyboards appeared at the beginning of the Années 1960, at the same time as the first systems usable in Ligne of order. They were divided into four classes:

final with balls, with or without setting out of plug of a line of text before sending (example IBM 2741);
keyboards coupled to a screen-plug;
keyboards of the teleprinter type, with or without punching reader/of ribbon (ASR33, KSR33);
keyboards coupled to screens full-screen at programmable zones (series IBM 327x).

Towards end of the year 70, the text taking more and more importance in the treated data, the keyboards were systematically personalized according to the countries, either by the large manufacturers themselves, or by local companies (it cost of it only the burning of a ROMANIAN and the serigraphy of some keys).

The data-processing keyboards are similar seemingly, and sometimes in their operation, with the keyboards of the typewriters.

The keyboards were created so as to be similar to the keyboards of the typewriters, in order not to divert the users. In the years 1980, each home computer had the keyboard integrated in the central processing unit. This means that each computer had a different keyboard potentially. However, of the national characteristics ended up appearing.

Keyboard PC was taken again by IBM according to work of Yves Neuville, which led to the ISO standard governing the provision of the keyboards. The keyboards of the machines functioning with Mac OS and Sun were designed by their respective firms (Apple and Sun).

Successive additions took place: Numeric keypad, function keys, keys multimedia.

The provision

The configuration of the majority of the data-processing and office automation keyboards is governed by the standard ISO 9995. This standard is the fruit of work initiated by the French Association of standardization (AFNOR) in 1984, under the direction of Bernard Vaucelle, at the request of Alain Souloumiac. Following various adventures which led to the interruption of this work in France, they were taken again with the international plan by the largest world specialists at this meeting in Berlin in 1985. They were concluded their within the International organization of standardization (ISO) under the direction of Yves Neuville.

The number of keys and their provision depend on the country or of the language used but a keyboard of desktop machine comprises always a little more than 100 keys (102 in France for the basic PC, which pass to 105 with the addition of three Windows keys on many models). The keyboards are heirs for their part “text” of the provisions of the typewriters.

The keyboards are characterized by their national characteristics (national characters) and sometimes techniques (blank keys). The computer - or at least the control unit when there is one of them - must thus have a specific table (plane of coding) associating a scan code (code hardware of the key) with a character ASCII of a Page of code given, or a sequence Unicode on the more recent systems.

Several provisions of the keys exist: keyboard AZERTY, keyboard QWERTY, keyboard QWERTZ and keyboard DVORAK. For each one of these provisions, national alternatives exist. For example, the AZERTY French is not the same one as the Belgian AZERTY , and the German QWERTZ is not the same one as the QWERTZ Suisse.

Special keys

keys of combination: Ctrl, maj, Alt or option on Mac keyboard, Alt gr., order or méta on keyboard of MIT, Windows, fn;
keys of locking: Stop défil, Verr num ( Num Lock ), To lock maj ( Capes Lock );
dead keys and composes;
keys of navigation: directional arrows, run (preceding page, following, fine beginning and );
keys of text: space, entered, Retour postpones, inser, suppr, , Numeric keypad;
keys systems: Syst or Impr. screen, pause Attn, échap, finely, function, keys of management of food (I/O, to put in day before, to awake).

Connector industry

The keyboards of first PC (PC/G, PC/XT and PC/AT) used connectors of the type DIN. The connector named PS/2, smaller, replaced it in 1987, by preserving however electric compatibility with connector DIN.

The keyboards of the Mac computers used connector industries ADB, then the USB was generalized in 1998. For the PC, different standard from connector industry exist:

DIN: 5 pins of connection + shielding (round) which one can meet on old computers. It completely disappeared from the modern computers.
PS/2 : 6 pins of connection + shielding (round). It replaces connector DIN henceforth; only physical connectivity being modified, of the adapters allow an interconnection in a direction or the other between these two modes of connection. This change of connector, in 1987, not being able to be justified by any technical reason (except, with the rigor, of the laptops or the constraints of place are present) certain see an argument marketing there to sell new keyboards and adapters… The life of this connector is threatened today by the USB presented hereafter
USB: rectangular with four pins + shielding. It will probably in the short or medium term replace the connector PS/2, which has now evil to justify its presence within sight of the omnipresence of the USB on all the computers since 1998, qu ' they are of type PC or Mac. But that presents a disadvantage: that to monopolize a port USB moreover, just for the keyboard. When it is known that it quasi entirety of peripherals PC and Mac current (printers, scanners, mouse, modems, webcams, key USB, external hard drives, etc) use this port, one is in right to wonder whether that is a good thing: one can be with court of free ports USB. The use of " hubs" USB solve this problem, but many others pose some, (saturation of band-width of the port, overconsumption of resources machine, etc). Moreover, as in 1987 at the time of the disappearance of the connector DIN, that will allow the manufacturers to sell new keyboards and adapters.
Connection without wire: Infra-red IrDA (little used), Bluetooth, radio - emission. The keyboards using this technology develop at high speed since 2004. Technologies of transmission without wire use a receiver which is tributary of the one of the modes of connection " standard" of a keyboard: USB or port PS/2. The " without-fil" thus eliminate the need from the wire, but not from the connector (Except in certain cases for the Bluetooth keyboard if a receiver of this type is integrated into the computer).

The great disadvantage of the keyboards without wire is the need for feeding them in energy, which results replacing the piles regularly or in reloading them, which induces by extension an additional pollution which had with the recycling of the piles.

Quality and precision

In spite of their similar aspect, all the keyboards are not equal in front of technology and the precision. In the choice of a keyboard, several characteristics must be taken into account.

First of all, the person who seeks a powerful keyboard must make sure that the provision of its keys will enable him to carry out a fast and precise work, while avoiding to him stopping striking to seek a key not accessible enough to the hand. Then, it is a question of testing the precision of the key. Indeed, the keys of the most advanced keyboards contain a spring which, instead of being inserted, nothing but does yield, thus making it possible the user to know that the key was taken into account while improving the keying speed. These new models of keys, still too not very widespread through the various marks of keyboards, thus offer the precision of the most complete striking. These two elements are indissociable concern the speed of writing. If the keys are sufficiently flexible and if they are well laid out, the general organization of the keyboard will have to allow a fast and intelligent writing.

Keyboards owners

The electronics of all these keyboards functions in a similar way under all the operating systems, which do not see it besides. It in general includes/understands a microprocessor which filters the possible rebounds, and three indicators close or not to the respective keys which order their lighting or extinction.

The essential difference between the keyboards of the IBM type and Unix type is the separation of the functions, in the first, between character keys (which strike a character or an accent which will deteriorate the next character), and function key being used to carry out specific requests. At the beginning standardized (of F1 with F12), the function keys were complementary of 13 debanalized keys ( Origine , Fin , preceding Page , following Page , Insertion , arrows of cursor,…) with the wire of the time, to which were still added on certain keyboards of the keys Internet and Multimédia .

Macintosh keyboard

On the keyboards Macintosh, one finds two keys particular: the Touche orders (or Touche apple) and the Touche option (which one can compare to the Touche alt GCV, and which bears besides also this name). The Touche orders is located on both sides Barre of space, and the Touche option is located between the Touche controls (or Ctrl) and the Touche orders.

For the aficionados of Macintosh, these keys are placed thus better, thought better (as the directly accessible key @). In this manner, they, the key explain which is used for the majority of the Raccourcis keyboard, the Touche order, are located under the inch (on both sides of the Barre of space), inch which is used only little for striking. This key is thus easily atteignable and makes it possible to use a great number of short cuts. In practice, the Ctrl keys and Alt (on the left) of the PC are also ordered they with the inch, like Alt-gr. (on the right).

Keyboard PC

Keyboard PC is most widespread.

It introduced the standard of the debanalized keys:

Inser tion and suppression;
beginning and end;
preceding page and following page;
more twelve keys known as “of function” taken again of the keyboards of Mainframe S (where they occupied on the other hand the place of the numeric keypad, in 4 lines of 3).

There exists a standard by couple language/country. The keyboard with the French standard is characterized by a direct availability of the key µ (for microsecond, microfarad, microampere, etc)

Windows keyboard

There really does not exist of Windows keyboard, even if several keyboards of PC (Linux or Windows) have three Windows keys. On the other hand, the way in which the keyboard is managed (in a software way) is specific to each Operating system, and sometimes even with a Input method in the only graphic subsystem of this one (case of X-Window).

Windows management

Microsoft, by its size, with the possibility of influencing many things in data processing. It did not make however little to improve the Ergonomie of keyboard PC, except the Natural Keyboard , which met a success of regard.

The provision of the keyboard thus remains primarily that of keyboard AT defined in 1983, only innovation since the first keyboard of PC of 1981: blocks of keys spaced better, orders of arrows in T reversed, and the three indicators numerical Locking , Locking capital letters and Stop of run which missed with the first PC.

Microsoft added an advertizing key, the key Windows , evoking the key Commande computers Mac OS, which opens the menu to start and is used in short cuts. The computers IBM Thinkpad did not have, until 2006 and their series 60, a key Windows .

One can reproach management by Windows of the keyboard:

the choice of the key Controls (Ctrl) for the short cuts keyboards, the most offset, therefore difficult of access, and which obliges to move the hand to reach it, therefore to stop striking;
the management of the accents: there does not exist in a direct way to make a E on a French keyboard Azerty, unless using a coded representation indicated by the table of the characters: it is enough to maintain the Alt key inserted during the striking of its code 0201 using the numeric keypad, then to slacken the Alt key;
the absence of capital key, replaced by a key high of breakage (Shift), as on the typewriters 19th century (which does not make it possible to use the punctuation or the accents).

Sun keyboard

The Sun keyboards are characterized in particular by a block from 10 keys on the left, of which a key is used to copy the selection, and a key to be stuck (mechanism Copy-to stick).

They also have a key Compose making it possible to enter of the special characters, in particular the accentuated characters of the Latin alphabet, by using combinations such as “Compose+o”, then “E” to obtain “œ” or “Compose+e” then apostrophizes for “E”.

This system is very widespread on the machines revolving under Unix (such as the Sun stations), but it is also implemented under Linux (one must then be often satisfied with the key Windows ).

Others

Many computer manufacturers add keys multimedia, or which make it possible to launch or to control an application.

Compaq manufactured some time of the keyboards whose indicators numerical Verrouillage , Verrouillage capital letters and Arrêt of run were inserted in the keys even making it possible to change the state it, which avoided an effort of memorizing to the user. These keys are not used much any more since the generalization of Windows, of the free little programs making it possible even to inhibit the operation of the two first. On the keyboards of Macintosh, a diode is, still, present today in the capital key of locking.

Others

There exists a symbol in the Character set Unicode symbolizing a keyboard: ⌨ (U+2328).

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