Text mode
Encyclopedia
Text mode is a kind of computer display mode in which the content of the screen is internally represented in terms of character
s rather than individual pixel
s. Typically, the screen consists of a uniform rectangular grid of character cells, each of which contains one of the characters of a character set. Text mode is contrasted to all points addressable
(APA) mode or other kinds of computer graphics
modes.
Text mode video rendering came to prominence in the early 1970s, when video-oriented text terminals started to replace teleprinter
s in the interactive use of computers.
Text mode applications communicate with the user with command-line interface
s and text user interface
s. Many character sets used in text mode applications also contain a limited set of predefined semi-graphical characters usable for drawing boxes
, and other rudimentary graphics which can be used to highlight the content or to simulate widget or control interface objects found in GUI
programs. A typical example is the IBM
code page 437
character set.
The advantages of text modes as compared to graphics modes include lower memory consumption and faster screen manipulation. At the time text terminals were replacing teleprinters in the 1970s, the extremely high cost of random access memory in that period made it exorbitantly expensive to install enough memory for a computer to simultaneously store the current value of every pixel on a screen (the first Macintosh
was groundbreaking and very expensive because it attempted to do precisely that). Text mode avoids the problem of expensive memory by having dedicated display hardware re-render each line of text from characters into pixels with each scan of the screen by the cathode ray. In turn, the display hardware needs only enough memory to store the pixels equivalent to one line of text (or even less) at a time. Thus, the computer only stores and knows about the underlying text characters (hence the name "text mode") and the only location where the actual pixels representing those characters exist as a single unified image is the screen itself, as viewed by the user.
In addition, text mode applications have relatively low bandwidth requirements in remote terminal use. An obvious disadvantage of text mode is the restricted screen content.
An important characteristic of text mode programs is that they assume monospace font
s, where every character has the same width on screen, which allows to easily maintain the vertical alignment when displaying semi-graphical characters. This was an analogy of early mechanical printers which had fixed pitch (teleprinter
s and daisy wheel printer
s, etc.). This way, the output seen on the screen could be sent directly to the printer maintaining exactly the same format..
Depending on the environment, the screen buffer
can be directly addressable. Programs that display output on remote video terminal
s must issue special control sequences to manipulate the screen buffer. The most popular standards for such control sequences are ANSI
and VT100
.
Programs accessing the screen buffer through control sequences may lose synchronization with the actual display, so that many text mode programs have a redisplay everything command, often associated with the Ctrl
-L key combination.
The border between text mode and graphical programs can sometimes be fuzzy, especially on the PC's VGA hardware, because many later text mode programs tried to push the model to the extreme by playing with the video controller. For example, they redefined the character set in order to create custom semi-graphical characters, or even created the appearance of a graphical mouse by redefining the appearance of the characters over which the mouse was shown at a given time.
Text mode rendering with user-defined characters has also been useful for 2D computer and video games because the game screen can be manipulated much faster than with pixel-oriented rendering.
Many modern programs with a graphical interface simulate the display style of text mode programs, notably when it is important to preserve the vertical alignment of text, e.g., during computer programming
. There exist also software components to emulate text mode, such as terminal emulator
s or command line console
s. In Microsoft
Windows
, the Win32 console
usually opens in emulated, graphical window mode it can be switched to full screen, true text mode and vice versa by pressing the Alt
and Enter
keys together (this is no longer supported in Windows 7).
Linux
virtual console
operates in text mode. Most Linux distributions support several virtual console screens, accessed by pressing Ctrl
, Alt and a function key
together.
. Character memory or a pattern table contains a raster font in use, where each character is represented by a dot matrix
(a matrix
of bit
s), so the character memory could be considered as a three-dimensional bit array. Display matrix (a text buffer, screen buffer, or nametable) tracks which character is in each cell. In the simple case the display matrix can be just a matrix of code point
s (so named character pointer table), but it usually stores for each character position not only a code, but also attributes.
|- bgcolor=#99CCFF
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01010101
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In the case of raster scan
output, which is the most common for computer monitors, the corresponding video signal is made by the character generator, a special electronic unit similar to devices with the same name used in video technology
. The video controller has two registers: scan line counter and dot counter, serving as coordinates in the screen dot matrix. Each of them must be divided by corresponding glyph size to obtain an index in the display matrix; the remainder
is an index in glyph matrix. If glyph size equals to 2n
, then it is possible just to use n low bits of a binary register as an index in glyph matrix, and the rest of bits as an index in the display matrix — see the scheme.
The character memory resides in a read-only memory
in some systems. Other systems allow the use of RAM for this purpose, making it possible to redefine the typeface
and even the character set for application-specific purposes. The use of RAM-based characters also facilitates some special techniques, such as the implementation of a pixel-graphics frame buffer by reserving some characters for a bitmap and writing pixels directly to their corresponding character memory. In some historical graphics chips, including the TMS9918, the MOS Technology VIC
, and the Game Boy
graphics hardware, this was actually the canonical way of doing pixel graphics.
Text modes often assign attributes to the displayed characters. For example, the VT100
terminal allows each character to be underlined, brightened, blinking or inverse. Color-supporting devices usually allow the color of each character, and often the background color as well, to be selected from a limited palette
of colors. These attributes can either coexist with the character indices or use a different memory area called color memory or attribute memory.
Some text mode implementations also have the concept of line attributes. For example, the VT100-compatible line of text terminals supports the doubling of the width and height of the characters on individual text lines.
computers. They are listed on the table below:
MDA text could be emphasized with bright, underline, reverse and blinking attributes.
Video cards in general are backward compatible, i.e. EGA supports all MDA and CGA modes, VGA supports MDA, CGA and EGA modes.
By far the most common text mode used in DOS environments, and initial Windows consoles, is the default 80 columns by 25 rows, or 80×25, with 16 colors. This mode was available on practically all IBM
and compatible personal computers. Several programs, such as terminal emulator
s, used only 80×24 for the main display and reserved the bottom row for a status bar
.
Two other VGA text modes, 90×43 and 90×50, exist but were very rarely used. The 40-column text modes were never very popular outside games and other applications designed for compatibility with television monitors, and were used only for demonstration purposes or with very old hardware.
Character sizes and graphical resolutions for the extended VESA
-compatible Super VGA text modes are manufacturer-dependent. Also on these display adapters, available colors can be halved from 16 to 8 when a second customized character set is employed (giving a total repertoire of 512 —instead the common 256— different graphic characters simultaneously displayed on the screen).
Some cards (e.g. S3
) supported custom very large text modes, like 100×37 or even 160×120. In Linux
systems, a program called SVGATextMode is often used with SVGA cards to set up very large console text modes.
Character (computing)
In computer and machine-based telecommunications terminology, a character is a unit of information that roughly corresponds to a grapheme, grapheme-like unit, or symbol, such as in an alphabet or syllabary in the written form of a natural language....
s rather than individual pixel
Pixel
In digital imaging, a pixel, or pel, is a single point in a raster image, or the smallest addressable screen element in a display device; it is the smallest unit of picture that can be represented or controlled....
s. Typically, the screen consists of a uniform rectangular grid of character cells, each of which contains one of the characters of a character set. Text mode is contrasted to all points addressable
All Points Addressable
All Points Addressable , in the context of a video monitor, dot matrix or any display device consisting of a pixel array, refers to an arrangement bits or cells which can be individually manipulated, as opposed to rewriting the whole array every time a pixel changes.Generally, text modes are not...
(APA) mode or other kinds of computer graphics
Computer graphics
Computer graphics are graphics created using computers and, more generally, the representation and manipulation of image data by a computer with help from specialized software and hardware....
modes.
Text mode video rendering came to prominence in the early 1970s, when video-oriented text terminals started to replace teleprinter
Teleprinter
A teleprinter is a electromechanical typewriter that can be used to communicate typed messages from point to point and point to multipoint over a variety of communication channels that range from a simple electrical connection, such as a pair of wires, to the use of radio and microwave as the...
s in the interactive use of computers.
Text mode applications communicate with the user with command-line interface
Command-line interface
A command-line interface is a mechanism for interacting with a computer operating system or software by typing commands to perform specific tasks...
s and text user interface
Text user interface
TUI short for: Text User Interface or Textual User Interface , is a retronym that was coined sometime after the invention of graphical user interfaces, to distinguish them from text-based user interfaces...
s. Many character sets used in text mode applications also contain a limited set of predefined semi-graphical characters usable for drawing boxes
Box drawing characters
Box drawing characters, also known as line drawing characters, or pseudographics, are widely used in text user interfaces to draw various frames and boxes...
, and other rudimentary graphics which can be used to highlight the content or to simulate widget or control interface objects found in GUI
Gui
Gui or guee is a generic term to refer to grilled dishes in Korean cuisine. These most commonly have meat or fish as their primary ingredient, but may in some cases also comprise grilled vegetables or other vegetarian ingredients. The term derives from the verb, "gupda" in Korean, which literally...
programs. A typical example is the IBM
IBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
code page 437
Code page 437
IBM PC or MS-DOS code page 437 is the character set of the original IBM PC. It is also known as CP 437, OEM 437, PC-8, MS-DOS Latin US or sometimes misleadingly referred to as the OEM font, High ASCII or Extended ASCII....
character set.
The advantages of text modes as compared to graphics modes include lower memory consumption and faster screen manipulation. At the time text terminals were replacing teleprinters in the 1970s, the extremely high cost of random access memory in that period made it exorbitantly expensive to install enough memory for a computer to simultaneously store the current value of every pixel on a screen (the first Macintosh
Macintosh
The Macintosh , or Mac, is a series of several lines of personal computers designed, developed, and marketed by Apple Inc. The first Macintosh was introduced by Apple's then-chairman Steve Jobs on January 24, 1984; it was the first commercially successful personal computer to feature a mouse and a...
was groundbreaking and very expensive because it attempted to do precisely that). Text mode avoids the problem of expensive memory by having dedicated display hardware re-render each line of text from characters into pixels with each scan of the screen by the cathode ray. In turn, the display hardware needs only enough memory to store the pixels equivalent to one line of text (or even less) at a time. Thus, the computer only stores and knows about the underlying text characters (hence the name "text mode") and the only location where the actual pixels representing those characters exist as a single unified image is the screen itself, as viewed by the user.
In addition, text mode applications have relatively low bandwidth requirements in remote terminal use. An obvious disadvantage of text mode is the restricted screen content.
An important characteristic of text mode programs is that they assume monospace font
Monospace font
A monospaced font, also called a fixed-pitch or non-proportional font, is a font whose letters and characters each occupy the same amount of horizontal space...
s, where every character has the same width on screen, which allows to easily maintain the vertical alignment when displaying semi-graphical characters. This was an analogy of early mechanical printers which had fixed pitch (teleprinter
Teleprinter
A teleprinter is a electromechanical typewriter that can be used to communicate typed messages from point to point and point to multipoint over a variety of communication channels that range from a simple electrical connection, such as a pair of wires, to the use of radio and microwave as the...
s and daisy wheel printer
Daisy wheel printer
Daisy wheel printers use an impact printing technology invented in 1969 by David S. Lee at Diablo Data Systems. It uses interchangeable pre-formed type elements, each with typically 96 glyphs, to generate high-quality output comparable to premium typewriters such as the IBM Selectric, but two to...
s, etc.). This way, the output seen on the screen could be sent directly to the printer maintaining exactly the same format..
Depending on the environment, the screen buffer
Screen buffer
In computing, screen buffer is a part of computer memory used by a computer application for the representation of the content to be shown on the computer display....
can be directly addressable. Programs that display output on remote video terminal
Computer terminal
A computer terminal is an electronic or electromechanical hardware device that is used for entering data into, and displaying data from, a computer or a computing system...
s must issue special control sequences to manipulate the screen buffer. The most popular standards for such control sequences are ANSI
ANSI escape code
ANSI escape sequences are characters embedded in the text used to control formatting, color, and other output options on video text terminals. Almost all terminal emulators designed to show text output from a remote computer, and to show text output from local software, interpret at least some of...
and VT100
VT100
The VT100 is a video terminal that was made by Digital Equipment Corporation . Its detailed attributes became the de facto standard for terminal emulators.-History:...
.
Programs accessing the screen buffer through control sequences may lose synchronization with the actual display, so that many text mode programs have a redisplay everything command, often associated with the Ctrl
Control key
In computing, a Control key is a modifier key which, when pressed in conjunction with another key, will perform a special operation ; similar to the Shift key, the Control key rarely performs any function when pressed by itself...
-L key combination.
Text mode rendering with user-defined characters has also been useful for 2D computer and video games because the game screen can be manipulated much faster than with pixel-oriented rendering.
Many modern programs with a graphical interface simulate the display style of text mode programs, notably when it is important to preserve the vertical alignment of text, e.g., during computer programming
Computer programming
Computer programming is the process of designing, writing, testing, debugging, and maintaining the source code of computer programs. This source code is written in one or more programming languages. The purpose of programming is to create a program that performs specific operations or exhibits a...
. There exist also software components to emulate text mode, such as terminal emulator
Terminal emulator
A terminal emulator, terminal application, term, or tty for short, is a program that emulates a video terminal within some other display architecture....
s or command line console
Win32 console
Win32 console is a text user interface implementation within the system of Windows API, which runs console applications. A Win32 console has a screen buffer and an input buffer, and is available both as a window or in text mode screen, with switching back and forth available via Alt-Enter...
s. In Microsoft
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
, the Win32 console
Win32 console
Win32 console is a text user interface implementation within the system of Windows API, which runs console applications. A Win32 console has a screen buffer and an input buffer, and is available both as a window or in text mode screen, with switching back and forth available via Alt-Enter...
usually opens in emulated, graphical window mode it can be switched to full screen, true text mode and vice versa by pressing the Alt
Alt key
The Alt key on a computer keyboard is used to change the function of other pressed keys. Thus, the Alt key is a modifier key, used in a similar fashion to the Shift key. For example, simply pressing "A" will type the letter a, but if you hold down either Alt key while pressing A, the computer...
and Enter
Enter key
In computer keyboards, the enter key in most cases causes a command line, window form, or dialog box to operate its default function...
keys together (this is no longer supported in Windows 7).
Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
virtual console
Virtual console
A virtual console – also known as a virtual terminal – is a conceptual combination of the keyboard and display for a computer user interface. It is a feature of some operating systems such as UnixWare, Linux, and BSD, in which the system console of the computer can be used to switch between...
operates in text mode. Most Linux distributions support several virtual console screens, accessed by pressing Ctrl
Control key
In computing, a Control key is a modifier key which, when pressed in conjunction with another key, will perform a special operation ; similar to the Shift key, the Control key rarely performs any function when pressed by itself...
, Alt and a function key
Function key
A function key is a key on a computer or terminal keyboard which can be programmed so as to cause an operating system command interpreter or application program to perform certain actions...
together.
Technical basis
A video controller implementing a text mode usually uses two distinct areas of memoryVideo memory
Video memory is a term generally used in computers to describe some form of writable memory, usually RAM, dedicated to the purpose of holding the information necessary for a graphics card to drive a display device...
. Character memory or a pattern table contains a raster font in use, where each character is represented by a dot matrix
Dot matrix
A dot matrix is a 2-dimensional array of LED used to represent characters, symbols and images.Typically the dot matrix is used in older computer printers and many digital display devices. In printers, the dots are usually the darkened areas of the paper...
(a matrix
Matrix (mathematics)
In mathematics, a matrix is a rectangular array of numbers, symbols, or expressions. The individual items in a matrix are called its elements or entries. An example of a matrix with six elements isMatrices of the same size can be added or subtracted element by element...
of bit
Bit
A bit is the basic unit of information in computing and telecommunications; it is the amount of information stored by a digital device or other physical system that exists in one of two possible distinct states...
s), so the character memory could be considered as a three-dimensional bit array. Display matrix (a text buffer, screen buffer, or nametable) tracks which character is in each cell. In the simple case the display matrix can be just a matrix of code point
Code point
In character encoding terminology, a code point or code position is any of the numerical values that make up the code space . For example, ASCII comprises 128 code points in the range 0hex to 7Fhex, Extended ASCII comprises 256 code points in the range 0hex to FFhex, and Unicode comprises 1,114,112...
s (so named character pointer table), but it usually stores for each character position not only a code, but also attributes.
! bgcolor=#FFFFFF |L\C>
0
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1
11111111
00001111
00110011
01010101
00…
00…
01…
>-
| bgcolor=#FFCC99 |00000
| rowspan=8 |
|-
| bgcolor=#FFCC99 |00001
| bgcolor=#FFCC99 |00010
| bgcolor=#FFCC99 |00011
| bgcolor=#FFCC99 |00100
| bgcolor=#FFCC99 |00101
| bgcolor=#FFCC99 |00110
| bgcolor=#FFCC99 |00111
In the case of raster scan
Raster scan
A raster scan, or raster scanning, is the rectangular pattern of image capture and reconstruction in television. By analogy, the term is used for raster graphics, the pattern of image storage and transmission used in most computer bitmap image systems...
output, which is the most common for computer monitors, the corresponding video signal is made by the character generator, a special electronic unit similar to devices with the same name used in video technology
Character generator
A character generator, often abbreviated as CG, is a device or software that produces static or animated text for keying into a video stream. Modern character generators are computer-based, and can generate graphics as well as text...
. The video controller has two registers: scan line counter and dot counter, serving as coordinates in the screen dot matrix. Each of them must be divided by corresponding glyph size to obtain an index in the display matrix; the remainder
Modulo operation
In computing, the modulo operation finds the remainder of division of one number by another.Given two positive numbers, and , a modulo n can be thought of as the remainder, on division of a by n...
is an index in glyph matrix. If glyph size equals to 2n
Power of two
In mathematics, a power of two means a number of the form 2n where n is an integer, i.e. the result of exponentiation with as base the number two and as exponent the integer n....
, then it is possible just to use n low bits of a binary register as an index in glyph matrix, and the rest of bits as an index in the display matrix — see the scheme.
The character memory resides in a read-only memory
Read-only memory
Read-only memory is a class of storage medium used in computers and other electronic devices. Data stored in ROM cannot be modified, or can be modified only slowly or with difficulty, so it is mainly used to distribute firmware .In its strictest sense, ROM refers only...
in some systems. Other systems allow the use of RAM for this purpose, making it possible to redefine the typeface
Typeface
In typography, a typeface is the artistic representation or interpretation of characters; it is the way the type looks. Each type is designed and there are thousands of different typefaces in existence, with new ones being developed constantly....
and even the character set for application-specific purposes. The use of RAM-based characters also facilitates some special techniques, such as the implementation of a pixel-graphics frame buffer by reserving some characters for a bitmap and writing pixels directly to their corresponding character memory. In some historical graphics chips, including the TMS9918, the MOS Technology VIC
MOS Technology VIC
The VIC , specifically known as the MOS Technology 6560 / 6561 , is the integrated circuit chip responsible for generating video graphics and sound in the Commodore VIC-20 home computer...
, and the Game Boy
Game Boy
The , is an 8-bit handheld video game device developed and manufactured by Nintendo. It was released in Japan on , in North America in , and in Europe on...
graphics hardware, this was actually the canonical way of doing pixel graphics.
Text modes often assign attributes to the displayed characters. For example, the VT100
VT100
The VT100 is a video terminal that was made by Digital Equipment Corporation . Its detailed attributes became the de facto standard for terminal emulators.-History:...
terminal allows each character to be underlined, brightened, blinking or inverse. Color-supporting devices usually allow the color of each character, and often the background color as well, to be selected from a limited palette
Palette (computing)
In computer graphics, a palette is either a given, finite set of colors for the management of digital images , or a small on-screen graphical element for choosing from a limited set of choices, not necessarily colors .Depending on the context In computer graphics, a palette is either a given,...
of colors. These attributes can either coexist with the character indices or use a different memory area called color memory or attribute memory.
Some text mode implementations also have the concept of line attributes. For example, the VT100-compatible line of text terminals supports the doubling of the width and height of the characters on individual text lines.
PC common text modes
Depending on the graphics adapter used, a variety of text modes are available on IBM PC compatibleIBM PC compatible
IBM PC compatible computers are those generally similar to the original IBM PC, XT, and AT. Such computers used to be referred to as PC clones, or IBM clones since they almost exactly duplicated all the significant features of the PC architecture, facilitated by various manufacturers' ability to...
computers. They are listed on the table below:
| Text res. | Char. size | Graphics res. | Colors | Adapters |
|---|---|---|---|---|
| 80×25 | 9×14 | 720×350 | B&W Text | MDA Monochrome Display Adapter The Monochrome Display Adapter introduced in 1981 was IBM's standard video display card and computer display standard for the PC. The MDA did not have any pixel-addressable graphics modes... , Hercules Hercules Graphics Card The Hercules Graphics Card was a computer graphics controller made by Hercules Computer Technology, Inc. which, through its popularity, became a widely supported display standard. It was common on IBM PC compatibles connected to a monochrome monitor . It supported one high resolution text mode and... |
| 40×25 | 8×8 | 320×200 | 16 colors | CGA Color Graphics Adapter The Color Graphics Adapter , originally also called the Color/Graphics Adapter or IBM Color/Graphics Monitor Adapter, introduced in 1981, was IBM's first color graphics card, and the first color computer display standard for the IBM PC.... , EGA |
| 80×25 | 8×8 | 640×200 | 16 colors | CGA, EGA |
| 80×25 | 8×14 | 640×350 | 16 colors | EGA Enhanced Graphics Adapter The Enhanced Graphics Adapter is the IBM PC computer display standard specification which is between CGA and VGA in terms of color and space resolution. Introduced in October 1984 by IBM shortly after its new PC/AT, EGA produces a display of 16 simultaneous colors from a palette of 64 at a... |
| 80×43 | 8×8 | 640×350 | 16 colors | EGA |
| 80×25 | 9×16 | 720×400 | 16 colors | VGA Video Graphics Array Video Graphics Array refers specifically to the display hardware first introduced with the IBM PS/2 line of computers in 1987, but through its widespread adoption has also come to mean either an analog computer display standard, the 15-pin D-subminiature VGA connector or the 640×480 resolution... |
| 80×30 | 8×16 | 640×480 | 16 colors | VGA Video Graphics Array Video Graphics Array refers specifically to the display hardware first introduced with the IBM PS/2 line of computers in 1987, but through its widespread adoption has also come to mean either an analog computer display standard, the 15-pin D-subminiature VGA connector or the 640×480 resolution... |
| 80×50 | 9×8 | 720×400 | 16 colors | VGA |
| 80×60 | 16 colors | VESA VESA BIOS Extensions VESA BIOS Extensions is a VESA standard, currently at version 3, that defines the interface that can be used by software to access compliant video boards at high resolutions and bit depths... -compatible Super VGA |
||
| 132×25 | 16 colors | VESA-compatible Super VGA | ||
| 132×43 | 16 colors | VESA-compatible Super VGA | ||
| 132×50 | 16 colors | VESA-compatible Super VGA | ||
| 132×60 | 16 colors | VESA-compatible Super VGA | ||
MDA text could be emphasized with bright, underline, reverse and blinking attributes.
Video cards in general are backward compatible, i.e. EGA supports all MDA and CGA modes, VGA supports MDA, CGA and EGA modes.
By far the most common text mode used in DOS environments, and initial Windows consoles, is the default 80 columns by 25 rows, or 80×25, with 16 colors. This mode was available on practically all IBM
IBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
and compatible personal computers. Several programs, such as terminal emulator
Terminal emulator
A terminal emulator, terminal application, term, or tty for short, is a program that emulates a video terminal within some other display architecture....
s, used only 80×24 for the main display and reserved the bottom row for a status bar
Status bar
A status bar, similar to a status line, is an information area typically found at the bottom of windows in a graphical user interface.A status bar is sometimes divided into sections, each of which shows different information. Its job is primarily to display information about the current state of...
.
Two other VGA text modes, 90×43 and 90×50, exist but were very rarely used. The 40-column text modes were never very popular outside games and other applications designed for compatibility with television monitors, and were used only for demonstration purposes or with very old hardware.
Character sizes and graphical resolutions for the extended VESA
VESA BIOS Extensions
VESA BIOS Extensions is a VESA standard, currently at version 3, that defines the interface that can be used by software to access compliant video boards at high resolutions and bit depths...
-compatible Super VGA text modes are manufacturer-dependent. Also on these display adapters, available colors can be halved from 16 to 8 when a second customized character set is employed (giving a total repertoire of 512 —instead the common 256— different graphic characters simultaneously displayed on the screen).
Some cards (e.g. S3
S3 Graphics
S3 Graphics, Ltd is an American company specializing in graphics chipsets. Although they do not have the large market share that they once had, they still produce graphics accelerators for home computers under the "S3 Chrome" brand name.-History:...
) supported custom very large text modes, like 100×37 or even 160×120. In Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
systems, a program called SVGATextMode is often used with SVGA cards to set up very large console text modes.
See also
- Text user interfaceText user interfaceTUI short for: Text User Interface or Textual User Interface , is a retronym that was coined sometime after the invention of graphical user interfaces, to distinguish them from text-based user interfaces...
- Text mode demosText mode demosText mode demos are real-time calculated computer animations which make use of the native text graphic mode common on the IBM PC compatibles. The text mode demo scene is one of many different facets of the demoscene....
— computer animations generated in text mode - TeletextTeletextTeletext is a television information retrieval service developed in the United Kingdom in the early 1970s. It offers a range of text-based information, typically including national, international and sporting news, weather and TV schedules...
- Text semigraphicsText semigraphicsText semigraphics is a primitive method used in early video hardware to emulate per pixel addressable graphics without having to implement the logic for a true "high resolution" mode....
- ASCII artASCII artASCII art is a graphic design technique that uses computers for presentation and consists of pictures pieced together from the 95 printable characters defined by the ASCII Standard from 1963 and ASCII compliant character sets with proprietary extended characters...
- Twin
- Code page 437Code page 437IBM PC or MS-DOS code page 437 is the character set of the original IBM PC. It is also known as CP 437, OEM 437, PC-8, MS-DOS Latin US or sometimes misleadingly referred to as the OEM font, High ASCII or Extended ASCII....