Mode 2 sets the high resolution mode dash pixels
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Answer:
Explanation:
ext mode is a computer display mode in which content is internally represented on a computer screen in terms of characters rather than individual pixels. 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 applications communicate with the user with command-line interfaces and text user interfaces. 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.
An important characteristic of text mode programs is that they assume monospace fonts, where every character has the same width on screen, which allows them to easily maintain the vertical alignment when displaying semi-graphical characters. This was an analogy of early mechanical printers which had fixed pitch (teleprinters and daisy wheel printers, 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 terminals 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.
Depending on the graphics adapter used, a variety of text modes are available on IBM PC compatible computers. They are listed on the table below:[3]
Text res. Char. size Graphics res. Colors Adapters
80×25 9×14 720×350 B&W Text MDA, Hercules
40×25 8×8 320×200 16 colors CGA, EGA
80×25 8×8 640×200 16 colors CGA, EGA
80×25 8×14 640×350 16 colors EGA
80×43 8×8 640×350 16 colors EGA
80×25 9×16 720×400 16 colors VGA
80×30 8×16 640×480 16 colors VGA
80×50 9×8 720×400 16 colors VGA
80×60 16 colors VESA-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 and compatible personal computers. Several programs, such as terminal emulators, used only 80×24 for the main display and reserved the bottom row for a status bar.
Two other VGA text modes, 80×43 and 80×50, 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, such as for use with split-screen terminal multiplexers.