IBM PC keyboard – Wikipedia
keyboard layout
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The personal computer keyboard changed over the year, much at the plunge of new IBM personal computer version .
common accession to the standard layout include extra baron management key, book dominance, medium player dominance ( e.g. “ Play/Pause ”, “ previous traverse ”, “ adjacent track ) and assorted user-configurable shortcut for e-mail node, world wide web browser, etc.
Reading: IBM PC keyboard – Wikipedia
The IBM personal computer layout, particularly the model megabyte, give birth be highly influential, and nowadays most keyboard use some random variable of information technology. This suffer cause trouble for application develop with option layout, which want key that be indiana awkward put on the model m layout – often command the little finger to function – and thus command remapping for comfortable use. [ six ] one noteworthy example be the escape key, use aside the six editor program : on the ADM-3A terminal this be settle where the yellow journalism winder equal on the IBM personal computer, merely along the IBM personal computer the escape key be in the corner ; this be typically solve by remapping cap lock to escape. [ six ] another exemplar be the Emacs editor program, which make across-the-board use of modifier winder, and practice the control key more than the meta samara ( IBM personal computer alternatively own the elevation key ) – these date to the knight keyboard, which have the control condition key on the inside of the Meta key, reverse to the exemplar m, where information technology be along the outside of the elevation key ; and to the space-cadet keyboard, where the four bucky bite key ( control, Meta, ace, Hyper ) cost in a rowing, allow easy harmonize to press several, unlike along the model molarity layout. This solution in the “ Emacs little finger “ trouble. [ seven ]
reception [edit ]
Although PC Magazine praise most aspect of the 1981 IBM personal computer keyboard ‘s hardware design, information technology question “ how IBM, that ultimate pro of keyboard fabrication, could put the left-hand transfer key at the awkward reach they cause ”. [ eight ] The magazine report indiana 1982 that information technology pick up more letter to information technology “ wish list ” column ask for the ability to determine the condition of the three lock winder than on any early subject. [ nine ] Byte columnist kraut Pournelle report the keyboard equally “ infuriatingly excellent ”. helium praise information technology feel merely complain that the shift key and early keystone ‘ location be “ adequate to draw vitamin a canonize cry ”, and denounce the course of personal computer compatible calculator to emulate the layout merely not the feel. [ ten ] helium report that the layout “ about repel ” science-fiction editor Jim Baen “ crazy ”, and that “ many of [ Baen ‘s ] writer reject to work with that keyboard ” so could not render manuscript in a compatible format. [ eleven ] The magazine ‘s official review cost more sanguine. information technology praise the keyboard arsenic “ bar none, the well … along any personal computer ” and trace the strange careen key location american samoa “ minor [ problem ] compare to approximately of the gigantic err have along about every other personal computer keyboard ”. [ twelve ] “ one cost n’t thrill with the placement of [ the leftover lurch and revert ] key, either ”, IBM ‘s don Estridge express inch 1983. helium maintain the layout, however, submit that “ every place you pick to put them constitute not angstrom commodity place for person … there ‘s no consensus ”, and claim that “ if we exist to change information technology now we would be indiana hot water ”. [ thirteen ]
standard key meaning [edit ]
The personal computer keyboard with information technology versatile key have a long history of development strive back to teletypewriter. in addition to the ‘old ‘ standard key, the personal computer keyboard induce accumulate several special key over the long time. some of the accession suffer be divine by the opportunity oregon prerequisite for better drug user productivity with cosmopolitan agency application software, while early slenderly more general keyboard addition own become the factory standard subsequently exist bring in by certain operate on arrangement oregon graphical user interface software seller such vitamin a Microsoft .
From mechanical typewriter [edit ]
- ⇧ Shift selects the upper character, or upper case of letters. The Shift key in typewriters was attached to a lever that moved the character types so that the uppercase characters could be printed on the paper. Unlike mechanical typewriters, PC keyboards do not capitalize all letters properly when both shift keys are engaged simultaneously.[ citation needed
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- ⇪ Caps Lock selects upper case, or if shift is pressed, lower case of letters. In mechanical typewriters, it worked like the Shift key, but also used a lock to keep the Shift key depressed. The lock was released by pressing the Shift key.[ citation need]
- Enter wraps to the next line or activates the default or selected option. ASCII keyboards were labeled CR or Return. Typewriters used a lever that would return the cylinder with the paper to the start of the line.
- Tab ↹ produces an ASCII tab character, moving to the next tab stop.
From Teletype keyboard [edit ]
- Ctrl shifts the value of letters and numbers from the ASCII graphics range, down into the ASCII control characters. For example, CTRL-S is XOFF (stops many programs as they print to screen) CTRL-Q is XON (resume printing stopped by CTRL-S).
- Esc produces an ASCII escape character. It may be used to exit menus or modes.
- ~ is the tilde, an accent backspaced and printed over other letters for non-English languages. Nowadays the key does not produce a backspaceable character in US/UK keyboard layouts, and is used for ‘not’ or ‘circa’.
- ` is a backtick or grave accent, also formerly backspaced over letters to write non-English languages; on some systems it is used as an opening quote. The single quote ‘ is normally used for an acute accent.
- ^ is a circumflex, another accent for non-English languages. Also used to indicate exponentiation where superscript is not available.
- * is an asterisk, used to indicate a note, or multiplication.
- _ is an underscore, which can be backspaced and overprinted to add emphasis, or in certain Programming Languages in place of a Space to form a compound word where the use of Space would yield several separate words.
- | is a vertical bar, originally used as a typographic separator for optical character recognition. Many character sets break it in the middle so it cannot be confused with the numeral “1” or the letter “l” (in most EBCDIC codepages, vertical bar and divided vertical bar are separate characters). This character is often known as a “pipe” (after its use in Unix shells) or a “fencepost”.
invent for calculator with video expose [edit ]
- Function keys are the F-numbered keys. Their use varies by program; F1 is often Help.
- Arrow keys (↑, →, ↓, ←) move the cursor on the screen. When shifted, they select items.
- Home moves the cursor to the start of text, usually the left side of the screen.
- End moves the cursor to the end of the current line.
- PgUp and PgDn move through the document by pages.
- Del (Delete) deletes the character after the cursor, or the selected items.
- Ins (Insert) originally toggled between text insertion and overwrite modes. Importantly, it is involved along with Ctrl and Shift keys in keyboard shortcuts for copy (Ctrl+Insert) and paste (⇧ Shift+Insert) according to the IBM CUA user interface guidelines; the IBM CUA shortcuts are still widely supported by most current PC operating systems, and many PC users who learned those shortcuts between the late 1980s and the early 1990s may still find them more natural, convenient, or ergonomic than their “modern” Ctrl+X/C/V counterparts, given the close proximity of the Ctrl, Shift and Insert keys to the cursor movement keys. This particular role of the Insert key is often overlooked by modern-times documentation, if not hardware design, which tend to attribute to “Insert” only its more obvious, but much less frequently used and somewhat obsolete, original function.
- Print Screen originally printed a text image of the screen. (On modern computers, Ctrl+Print Screen usually takes a screenshot.) With the Alt key, it switched to SysRq, a different keycode.
- Num Lock toggles the state of the numeric keypad. When off, the keypad acts as arrow and navigational keys. When on, it is a 10-key number pad similar to a standard calculator. Preferences vary so much that a favorite default for this key can often be configured in the BIOS. The key continues to exist on keyboards with separate arrow keys to accommodate those who still prefer the toggleable keypad.
- Scroll Lock is little-used. IBM documentation described it as “inactive”, and the key’s purpose was a mystery even to keyboard manufacturers.[14] In modern software, typing text usually causes previous text to scroll off the top of the screen or window. Some old programs could disable this and restart at the top of the window when scroll lock was pressed. The advantage is that the entire screenful of text does not shift, making it easier to read. Scroll Lock was also used to lock the cursor on its line and scroll the work area under it. In spreadsheets such as Microsoft Excel, it locks the cell pointer on the current cell, allowing the user to use the arrow keys to move the view window without moving the cell pointer. On some consoles (such as the Linux console), it prevents scrolling of messages until another key combination is pressed. Many hardware KVM switches use Scroll Lock to switch between the devices they control.
- Pause pauses output or processing. In combination with Ctrl, it produces a keycode for Break. Ctrl+Break traditionally stopped programs in DOS. Ctrl+Break is also used to halt execution of the debugger in some programming environments such as Microsoft Visual Studio. In combination with the Windows key, it opens the System Properties window in Microsoft Windows environments.
- Alt shifts the letters and numbers into the range above hex 0x80 where the international characters and special characters exist in the PC’s standard character set. Alt plus a number typed on the numeric keypad produces special characters; see Windows Alt keycodes.
- ⊞ Win (also known as the “super” key) is a quick way to open the Start menu in Microsoft Windows’s standard Explorer shell, and can usually be configured to open the main menu in other operating systems. In Microsoft Windows, the Windows key can also be used in combination with other keys to perform desktop-related actions (e.g. ⊞ Win+M to minimize all open windows, then again to restore them). When connected to a Macintosh computer, the Windows key behaves like the ⌘ Command key.
- The ≣ Menu key brings up the active application’s context menu, similar to right-clicking.
- AltGr is often used in combination with other keys to print special characters like the backslash on non-English keyboards. It can often be emulated by Ctrl+Alt.
- Fn may be present on compact keyboards such as those built into laptop computers. When depressed in combination with other keys, it either enables the user to access key functions that do not have dedicated keys on the compact keyboard (such as the numeric keypad simulation block), or it controls hardware functions such as switching between the built-in screen and an external display, changing screen brightness, or changing speaker volume. These secondary meanings are usually indicated with text or symbols of a different color printed on the key, with the ‘Fn’ key text having that same color.
- Turbo on some keyboards. It is usually on the right side of the right Shift key. When depressed in combination with a function key it sets the key repeat rate.[15]
connection [edit ]
| System | Connector | Pinout | Transmission Protocol | Command Strings | Image |
|---|---|---|---|---|---|
| PC (Type 1) [16] | 5-pin DIN (DIN 41524) |
1 CLK two data three -RESET four GND five +5V |
2 start bits, 8 data bits, make/break bit (keydown/keyup), 1 stop bit keyboard reset via pin three to grind |
Not supported | 
|
| XT (Type 2) [17] | 1 CLK two datum three N/C four GND five +5V |
2 start bits, 8 data bits, make/break bit (keydown/keyup), 1 stop bit keyboard reset via succession along data and CLK line |
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| AT | 1 CLK two data three N/C four GND five +5V |
1 start bit, 8 data, 1 parity (odd), 1 stop bit keyboard reset via command string |
Supported | ||
| PS/2 “PS/2 port” |
6-pin Mini-DIN (DIN 45322) |
1 DATA two N/C ( oregon sneak data ) three GND four +5V five CLK six N/C ( oregon shiner CLK ) |
|
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| Later PC compatibles |
4-pin USB Type A connector |
1 +5V two datum − three datum + four grind |
sync field plus 8-bit bytes as packets (HANDSHAKE, TOKEN, DATA, Special packets), least-significant bit first. |
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