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SAA5050
The Mullard SAA5050 was a 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 and the Poly-1. 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 block graphics character set, or various other effects. Full-screen resolution generated by the SAA5050 was 480×500 pixels, corresponding to 40×25 characters. Each character position therefore corresponded to a 12×20 pi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mullard SAA5050
The Mullard SAA5050 was a 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 and the Poly-1. 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 block graphics character set, or various other effects. Full-screen resolution generated by the SAA5050 was 480×500 pixels, corresponding to 40×25 characters. Each character position therefore corresponded to a 12×20 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BBC Micro
The British Broadcasting Corporation Microcomputer System, or BBC Micro, is a series of microcomputers and associated peripherals designed and built by Acorn Computers in the 1980s for the BBC Computer Literacy Project. Designed with an emphasis on education, it was notable for its ruggedness, expandability, and the quality of its operating system. An accompanying 1982 television series, ''The Computer Programme'', featuring Chris Serle learning to use the machine, was broadcast on BBC2. After the Literacy Project's call for bids for a computer to accompany the TV programmes and literature, Acorn won the contract with the ''Proton'', a successor of its Atom computer prototyped at short notice. Renamed the BBC Micro, the system was adopted by most schools in the United Kingdom, changing Acorn's fortunes. It was also successful as a home computer in the UK, despite its high cost. Acorn later employed the machine to simulate and develop the ARM architecture. While nine models ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mullard
Mullard Limited was a British manufacturer of electronic components. The Mullard Radio Valve Co. Ltd. of Southfields, London, was founded in 1920 by Captain Stanley R. Mullard, who had previously designed thermionic valves for the Admiralty before becoming managing director of the Z Electric Lamp Co. The company soon moved to Hammersmith, London and then in 1923 to Balham, London. The head office in later years was Mullard House at 1–19 Torrington Place, Bloomsbury, now part of University College London. Start-up In 1921, the directors were Sir Ralph Ashton (chairman), Basil Binyon of the Radio Communication Co, C.F. Elwell and S.R. Mullard (Managing Director). Partnership with Philips In 1923, to meet the technical demands of the newly formed BBC, Mullard formed a partnership with the Dutch manufacturer Philips. The valves (vacuum tubes) produced in this period were named with the prefix PM, for Philips-Mullard, beginning with the PM3 and PM4 in 1926. Mullard fina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philips P2000
The Philips P2000T home computer was Philips' first real entry in the home computer market in 1980, after the Philips Videopac G7000 game system (better known in North America as the Magnavox Odyssey2) which they already sold to compete with the Atari 2600 and similar game systems. There was also a P2000M version with an additional 80-column text card for use with a monochrome monitor. This version shipped with a monitor cabinet also housing a dual 5.25" floppy drive. The P2000C version, introduced in 1982, was portable. The P2000 systems can be emulated with the MESS software, and since 2015 they are part of MAME. Other emulators also exist. P2000T The P2000T was a Z80-based home computer that used a Mullard SAA5050 teletext display chip to produce the video picture and a small Mini-Cassette recorder for 42 kilobytes of mass storage capacity. The Mini-Cassette was treated as a floppy drive from the user's perspective while using the automatic search for a program (CLOAD command ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poly-1
The Poly-1 was a desktop computer designed in New Zealand for educational use. Background The Poly-1 was developed in 1980 by Neil Scott and Paul Bryant, who at the time were teaching electronics engineering at Wellington Polytechnic (now Massey University's Wellington campus), which the computer was named after. As with the Acorn BBC Micro in Britain, Scott and Bryant saw the increasing need for a fully integrated computer to serve the New Zealand school market, which had the blessing of then Education Minister Merv Wellington. After Scott and Bryant gathered a team of engineers and designers, DFC New Zealand Limited and Lower Hutt-based Progeni Systems — founded by Perce Harpham in 1968 — formed a joint venture, Polycorp, to market and build the Poly-1, which entered production in 1981. A distinctive fibreglass casing was designed to house the computer and monitor as an all-in-one unit, in a similar fashion to the Commodore PET. The Poly-1 came standard with a colour disp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acorn System 2
The Acorn Eurocard systems were a series of modular microcomputer systems based on rack-mounted Eurocards developed by Acorn Computers from 1979 to 1982, aimed primarily at industrial and laboratory use, but also home enthusiasts. The experience gained in developing this modular system strongly influenced the design of Acorn's first all-in-one home computer, the Acorn Atom, released in March 1980; and also much of the circuitry in its successor, the BBC Micro, first shown in late 1981. Acorn's final rack-based machine was the System 5, released in late 1982. The Eurocard business was then sold on to one of its principal resellers, Control Universal Ltd, which continued to develop various cards for industrial use based on the Acorn-standard bus during the 1980s, but ultimately went into receivership in 1989. Eurocards Placing the two Eurocards from the original Acorn Microcomputer onto a backplane made the system straightforward to expand in a modular way. The original I/O card, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teletext
A British Ceefax football index page from October 2009, showing the three-digit page numbers for a variety of football news stories Teletext, or broadcast teletext, is a standard for displaying text and rudimentary graphics on suitably equipped television sets. Teletext sends data in the broadcast signal, hidden in the invisible vertical blanking interval area at the top and bottom of the screen. The teletext decoder in the television buffers this information as a series of "pages", each given a number. The user can display chosen pages using their remote control. In broad terms, it can be considered as Videotex, a system for the delivery of information to a user in a computer-like format, typically displayed on a television or a dumb terminal, but that designation is usually reserved for systems that provide bi-directional communication, such as Prestel or Minitel. Teletext was created in the United Kingdom in the early 1970s by John Adams, Philips' lead designer for video di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
