IBM PC keyboard
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The
A well-known class of IBM PC keyboards is the Model M. Introduced in 1984 and manufactured by IBM, Lexmark, Maxi-Switch and Unicomp, the vast majority of Model M keyboards feature a buckling spring key design and many have fully swappable keycaps.
Keyboard layouts
The PC keyboard changed over the years, often at the launch of new
Name | Keys | Description | Image | |
---|---|---|---|---|
Model F (PC/XT) | 83 | Original left-hand side function key (F key) columns, F1 through F10; electronically incompatible with PC/AT keyboard types | IBM PC August 1981.
| |
PC/AT )
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84 | Additional SysRq ( LEDs for Caps/Scroll/Num lock
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Introduced August 1984. | |
Model M (Enhanced) | Additional navigation and control keys; 12 F keys in separate row along top, grouped F1–4, F5–8, and F9–12. Early models of Enhanced keyboard (notably those manufactured by Northgate Ltd.) maintained the layout with function keys on the left side, arranged in two columns of six pairs. This layout was more efficient for touch typists but was superseded in the marketplace by that with F-keys along the top. PS/2 released April 1987. There are different versions of the Enhanced keyboard layout: | |||
101 | standard US layout
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Introduced April 1986.[1] | ||
102 | European layouts
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Introduced April 1986. | ||
103 | Korean layout
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104 | Brazilian ABNT NBR 10346 variant 2 (alphanumeric portion) and 10347 (numeric portion).
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106 | Japanese JIS layout
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Windows[2] | Additional Microsoft Natural keyboard for use with the Windows 95 operating system.[4] Most modern PCs, whether supplied with Microsoft Windows or not, are now delivered with this layout.[5] Like the Enhanced layout, there are regional variants of the Windows keyboard layout:[5]
| |||
104 | standard US layout (as above) | |||
105 | European layouts[5] (as above) | |||
106 | Korean layout (as above) | |||
107 | Brazilian ABNT NBR 10346 variant 2 (alphanumeric portion) and 10347 (numeric), as above
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109 | Japanese layout (as above) |
Esc | F1 | F2 | F3 | F4 | F5 | F6 | F7 | F8 | F9 | F10 | F11 | F12 | PrtScn/ SysRq |
Scroll Lock |
Pause/ Break |
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Insert | Home | PgUp | Num
Lock |
∕ | ∗ | −
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Delete | End | PgDn | 7 | 8 | 9 | +
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4 | 5 | 6 | ||||||||||||||||||||||
↑ | 1 | 2 | 3 | Enter | ||||||||||||||||||||
← | ↓ | → | 0 Ins |
. Del |
Common additions to the standard layouts include additional
The IBM PC layout, particularly the Model M, has been extremely influential, and today most keyboards use some variant of it. This has caused problems for applications developed with alternative layouts, which require keys that are in awkward positions on the Model M layout – often requiring the pinkie to operate – and thus require remapping for comfortable use.
Reception
Although
"I wasn't thrilled with the placement of [the left Shift and Return] keys, either", IBM's
Standard key meanings
The PC keyboard with its various keys has a long history of evolution reaching back to teletypewriters. In addition to the 'old' standard keys, the PC keyboard has accumulated several special keys over the years. Some of the additions have been inspired by the opportunity or requirement for improving user productivity with general office application software, while other slightly more general keyboard additions have become the factory standards after being introduced by certain operating system or GUI software vendors such as Microsoft.
From mechanical typewriters
- ⇧ 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]
- ⇪ 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 needed]
- 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 character, moving to the next tab stop.
From Teletype keyboards
- 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 superscriptis not available.
- * is an asterisk, used to indicate a note, or multiplication.
- _ is an Spacewould yield several separate words.
- | is a 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".
Invented for computers with video displays
- Function keys are the F-numbered keys. Their use varies by program; F1 is often Help.
- Cursor 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.
- PgDnmove through the document by pages.
- Del (Delete) deletes the character after the cursor, or the selected items.
- IBM CUAuser 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.
- 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.
- KVM switchesuse 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.
- Windows Alt keycodes.
- ⊞ Macintosh computer, the Windows key behaves like the ⌘ Commandkey.
- ≣ Menu brings up the active application's context menu, in a similar way to right-clicking.
- Copilot opens Microsoft Copilot in Windows. It superseded the menu key on January 4, 2024.[15][16]
- 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 is present 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.[17]
Connection
System | Connector | Image | Pinout | Transmission Protocol | Command Strings |
---|---|---|---|---|---|
PC (Type 1) [18] | 5-pin DIN (DIN 41524) |
1 CLK 2 DATA |
2 start bits, 8 data bits, make/break bit (keydown/keyup), 1 stop bit keyboard reset via pin 3 to ground |
Not supported | |
XT (Type 2) [19] | 1 CLK 2 DATA |
2 start bits, 8 data bits, make/break bit (keydown/keyup), 1 stop bit keyboard reset via sequence on DATA and CLK lines | |||
AT | 1 CLK 2 DATA |
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 2 N/C (or MOUSE DATA) | |||
Later PC compatibles |
4-pin USB Type A connector |
1 +5V 2 Data − |
sync field plus 8-bit bytes as packets (HANDSHAKE, TOKEN, DATA, Special packets), least-significant bit first. |
See also
- Model F keyboard
- Model M keyboard
- Gateway AnyKey
- LK201
- Apple keyboard
- IBM Common User Access
Notes
- ^ IBM. IBM Enhanced Keyboard for the Personal Computer Announcement Letter. 1986-04-18.
- ^ ISBN 978-0-78971573-9.
- ISBN 978-0-78971636-1.
- ^ Corcoran, Cate T. (1994-09-05). "Microsoft keyboard ships". InfoWorld. p. 36.
- ^ ISBN 978-0-13268218-3.
- ^ a b Lee, Xah. "History of Emacs & vi Keys (Keyboard Influence on Keybinding Design)".
- ^ Lee, Xah. "How To Avoid The Emacs Pinky Problem". Retrieved 2009-11-08.
- ^ Edlin, Jim; Bunnell, David (February–March 1982). "IBM's New Personal Computer: Taking the Measure / Part One". PC Magazine. p. 42. Retrieved 20 October 2013.
- ^ Edlin, Jim (November 1982). "The PC's Keys". PC Magazine. p. 175. Retrieved 21 October 2013.
- ^ Pournelle, Jerry (November 1984). "NCC Reflections". BYTE. p. 361. Retrieved 23 October 2013.
- ^ Pournelle, Jerry (June 1983). "Zenith Z-100, Epson QX-10, Software Licensing, and the Software Piracy Problem". BYTE. Vol. 8, no. 6. p. 411. Retrieved 20 October 2013.
- ^ Williams, Gregg (January 1982). "A Closer Look at the IBM Personal Computer". BYTE. p. 36. Retrieved 19 October 2013.
- ^ Curran, Lawrence J.; Shuford, Richard S. (November 1983). "IBM's Estridge". BYTE. pp. 88–97. Retrieved 19 March 2016.
- ^ Sandler, Corey (January 1983). "Key Tronic's Soft Touch". PC Magazine. p. 347. Retrieved 21 October 2013.
- ^ "Microsoft's new Copilot key is the first big change to Windows keyboards in 30 years". The Verge. Vox Media. January 4, 2024. Retrieved January 6, 2024.
- ^ "Introducing a new Copilot key to kick off the year of AI-powered Windows PCs - Windows Experience Blog". blogs.windows.com. Retrieved 2024-01-06.
- ^ Belkin International. Knowledge Base Article 3532
- ^ International Business Machines Corporation (1983): IBM Personal Computer XT Technical Reference Manual, pages D-12 to D-13.
- ^ International Business Machines Corporation (1983): IBM Personal Computer XT Technical Reference Manual, pages D-14 to D-15.
External links
- Introduction to keyboards, at IBM at the Wayback Machine (archived 2018-10-28)
- Keyboard layouts: Logical keyboard layout registry index for countries and regions around the world, at IBM at the Wayback Machine (archived 2018-11-03)
- AT keyboard to XT converter discussion (Archived 2016-10-16 at the Wayback Machine)
- AT keyboard to XT converter source code