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Mullard SAA5050
The Mullard SAA5050 was a text mode#Technical basis, character generator chip for implementing the Teletext character set. The SAA5050 was used in teletext-equipped television sets, viewdata terminals, and microcomputers, most notably on computers like the Philips P2000 (1980), Acorn System 2 (1980), BBC Micro (1982), Malzak (computer), Malzak and the Poly-1, and Prestel adapters like the Tangerine Computer Systems#Tantel, AlphaTantel. This chip was also manufactured by Mullard for Philips. Operation The chip generated appropriate video output for a 7-bit input character code representing the current character on the text line, while keeping track of the effect of any of the various control characters defined by the teletext standard that had previously occurred in that text line, which could be used to change the foreground and background colour, switch to or from the alternate Semigraphics#Block graphics, block graphics character set, or various other effects. Full-screen resol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Control Character
In computing and telecommunications, a control character or non-printing character (NPC) is a code point in a character encoding, character set that does not represent a written Character (computing), character or symbol. They are used as in-band signaling to cause effects other than the addition of a symbol to the text. All other characters are mainly ''graphic characters'', also known as ''printing characters'' (or ''printable characters''), except perhaps for "space (punctuation), space" characters. In the ASCII standard there are 33 control characters, such as code 7, , which rings a terminal bell. History Prosigns for Morse code, Procedural signs in Morse code are a form of control character. A form of control characters were introduced in the 1870 Baudot code: NUL and DEL. The 1901 Murray code added the carriage return (CR) and line feed (LF), and other versions of the Baudot code included other control characters. The bell character (BEL), which rang a bell to alert op ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interlaced Video
Interlaced video (also known as interlaced scan) is a technique for doubling the perceived frame rate of a video display without consuming extra Bandwidth (signal processing), bandwidth. The interlaced signal contains two field (video), fields of a video frame captured consecutively. This enhances motion perception to the viewer, and reduces flicker (screen), flicker by taking advantage of the characteristics of the human visual system. This effectively doubles the time resolution (also called ''temporal resolution'') as compared to non-interlaced footage (for frame rates equal to field rates). Interlaced signals require a display that is natively capable of showing the individual fields in a sequential order. cathode-ray tube, CRT displays and ALiS plasma displays are made for displaying interlaced signals. Interlaced scan refers to one of two common methods for "painting" a video image on an electronic display screen (the other being progressive video, progressive scan) by sc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interpolated
In the mathematical field of numerical analysis, interpolation is a type of estimation, a method of constructing (finding) new data points based on the range of a discrete set of known data points. In engineering and science, one often has a number of data points, obtained by sampling or experimentation, which represent the values of a function for a limited number of values of the independent variable. It is often required to interpolate; that is, estimate the value of that function for an intermediate value of the independent variable. A closely related problem is the approximation of a complicated function by a simple function. Suppose the formula for some given function is known, but too complicated to evaluate efficiently. A few data points from the original function can be interpolated to produce a simpler function which is still fairly close to the original. The resulting gain in simplicity may outweigh the loss from interpolation error and give better performance in ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
