Character generator - Revision history

Jnc: +cat

2018-12-13T15:20:18Z

+cat

Jnc: Avoid redir

2018-09-15T18:00:31Z

Avoid redir

Jnc: Move VT11-specific content to new article on it

2018-06-07T23:50:07Z

Move VT11-specific content to new article on it

Jnc: A pretty good start

2018-06-06T17:06:34Z

A pretty good start

New page

A '''character generator''' is a [[hardware]] device which, given a particular character, provides the information needed to display that character on a [[CRT]].

On [[vector graphics]] displays (such as the console display on the [[CDC 6600]]), the character generator would produce a series of actual strokes, which made up the character. (On the CDC 6600, each stroke could be given as 0, 1 or 2 units of distance, along the horizontal and vertical axes, from the end of the prior stroke.)

On [[raster]] displays, it was typical to store characters in the generator as an array of bits. As the beam scanned across the screen, as it got to each character (i.e. the one being displayed at that location on the screen), the appropriate sequence of bits for the current row of that character (bearing in mind that a single row of characters would encompass a number of raster scans across the screen) would be read out and used to modulate the intensity of the beam.

The [[VT11 Graphic Display Processor]] used an odd intermediary; although it was a vector graphics device, for displaying characters, its character generator stored characters as arrays of pixels. To display a character, it did a raster-like scan over a small part of the screen, and displayed the character in much the same way a raster display does (above), although the raster scan used vertical strokes, not horizontal, as in a normal raster display.

← Older revision		Revision as of 15:20, 13 December 2018
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	* [[VT11 Graphic Display Processor]]		* [[VT11 Graphic Display Processor]]
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		+	[[Category: Device Basics‎‎]]

← Older revision		Revision as of 18:00, 15 September 2018
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−	A '''character generator''' is a [[hardware]] device which, given a particular character, provides the information needed to display that character on a [[CRT]].	+	A '''character generator''' is a [[hardware]] device which, given a particular character, provides the information needed to display that character on a [[Cathode ray tube\|CRT]].

	On [[vector graphics]] displays (such as the console display on the [[CDC 6600]]), the character generator would produce a series of actual strokes, which made up the character. (On the CDC 6600, each stroke could be given as 0, 1 or 2 units of distance, along the horizontal and vertical axes, from the end of the prior stroke.)		On [[vector graphics]] displays (such as the console display on the [[CDC 6600]]), the character generator would produce a series of actual strokes, which made up the character. (On the CDC 6600, each stroke could be given as 0, 1 or 2 units of distance, along the horizontal and vertical axes, from the end of the prior stroke.)

← Older revision		Revision as of 23:50, 7 June 2018
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	On [[raster]] displays, it was typical to store characters in the generator as an array of bits. As the beam scanned across the screen, as it got to each character (i.e. the one being displayed at that location on the screen), the appropriate sequence of bits for the current row of that character (bearing in mind that a single row of characters would encompass a number of raster scans across the screen) would be read out and used to modulate the intensity of the beam.		On [[raster]] displays, it was typical to store characters in the generator as an array of bits. As the beam scanned across the screen, as it got to each character (i.e. the one being displayed at that location on the screen), the appropriate sequence of bits for the current row of that character (bearing in mind that a single row of characters would encompass a number of raster scans across the screen) would be read out and used to modulate the intensity of the beam.

−	~~The~~ [[VT11 Graphic Display Processor]] used an odd intermediary; although it was a vector graphics device, for displaying characters, its character generator stored characters as arrays of pixels. To display a character, it did a raster-like scan over a small part of the screen, and displayed the character in much the same way a raster display does (above), although the raster scan used vertical strokes, not horizontal, as in a normal raster display.	+	==See also==
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		+	* [[VT11 Graphic Display Processor]]