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TK90X
The TK90X was the first Brazilian ZX Spectrum clone made in 1985 by Microdigital Electrônica, a company located in São Paulo, Brazil, that had manufactured some ZX81 clones (TK82C, TK83 and TK85) and ZX80 clones (TK80, TK82) before. Technical details The case was a little taller than the original Spectrum and the keyboard placement was equal to the original keyboard, except for some additional commands that did not exist in the Spectrums (for characters defined by the user — UDG — in the place of the 'Pound' symbol, and the 'Trace' function in BASIC), and included specific Portuguese and Spanish characters such as ç and ñ, as well as accented vowels. The two versions were the 16 KB and 48 KB of RAM. They contained the same processor (Z80A), running at 3.58 MHz and a ROM chip, some RAM chips (old dynamic RAMs 4116 and 4416). Microdigital reverse engineered a CMOS integrated circuit (IC) with similar functionality to the original Bipolar IC ULA from Sin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TK90X
The TK90X was the first Brazilian ZX Spectrum clone made in 1985 by Microdigital Electrônica, a company located in São Paulo, Brazil, that had manufactured some ZX81 clones (TK82C, TK83 and TK85) and ZX80 clones (TK80, TK82) before. Technical details The case was a little taller than the original Spectrum and the keyboard placement was equal to the original keyboard, except for some additional commands that did not exist in the Spectrums (for characters defined by the user — UDG — in the place of the 'Pound' symbol, and the 'Trace' function in BASIC), and included specific Portuguese and Spanish characters such as ç and ñ, as well as accented vowels. The two versions were the 16 KB and 48 KB of RAM. They contained the same processor (Z80A), running at 3.58 MHz and a ROM chip, some RAM chips (old dynamic RAMs 4116 and 4416). Microdigital reverse engineered a CMOS integrated circuit (IC) with similar functionality to the original Bipolar IC ULA from Sin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microdigital Eletrônica
Microdigital Eletrônica Ltda. was an influential Brazilian computer company in the 1980s, based in São Paulo. History Established in 1981 by the brothers George and Tomas Kovari (whose initials were the TK of the domestic computers line made by the company), its first product was the ''TK80'', a clone of the British microcomputer Sinclair ZX80. The company reached its height around 1985, with the launching of the TK90X (clone of the ZX Spectrum) and the ''TK-2000 II'', a personal computer partially compatible (at Applesoft BASIC level) with the Apple II+. At this time, it had approximately 400 employees in three plants (two in São Paulo and one in the Zona Franca de Manaus) and more than 700 peddlers spread for all Brazil. Although the logo of the company is identical to the earlier Microdigital Ltd of the United Kingdom the company is not related. Line of products A not extensive list of Microdigital's products: Home computers * TK80 (1981) * TK82 (1981) * TK82C (198 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microdigital Eletronica
Microdigital Eletrônica Ltda. was an influential Brazilian computer company in the 1980s, based in São Paulo. History Established in 1981 by the brothers George and Tomas Kovari (whose initials were the TK of the domestic computers line made by the company), its first product was the ''TK80'', a clone of the British microcomputer Sinclair ZX80. The company reached its height around 1985, with the launching of the TK90X (clone of the ZX Spectrum) and the ''TK-2000 II'', a personal computer partially compatible (at Applesoft BASIC level) with the Apple II+. At this time, it had approximately 400 employees in three plants (two in São Paulo and one in the Zona Franca de Manaus) and more than 700 peddlers spread for all Brazil. Although the logo of the company is identical to the earlier Microdigital Ltd of the United Kingdom the company is not related. Line of products A not extensive list of Microdigital's products: Home computers * TK80 (1981) * TK82 (1981) * TK82C (198 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TK95
The TK 95 microcomputer was a 1986 ZX Spectrum clone by Microdigital Eletrônica, a company located at São Paulo, Brazil. It was an evolution of the TK90X introduced the previous year. The case was redesigned (copied from the Commodore Plus/4) and the keyboard was said to be "semi-professional" (according to the Brazilian manufacturer), with the some additional Sinclair BASIC commands that did not exist in the ZX Spectrums (for user defined charactersUDG), and better compatibility with the original ZX Spectrum (compared to the TK90X). Like the Spectrum, the machine had 48 kilobytes of RAM. Inside, the same processor: Z80A running at 3.58 MHz, a 16 KB ROM chip and some RAM chips (old dynamic rams 4116 and 4416). Microdigital did some reverse engineering to develop a chip with the functions of the original ULA from Sinclair/Ferranti. The modulator was tuned to VHF channel 3 and the TV system was PAL-M (60 Hz). The cassette interface ran at a faster speed than the Spect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TK82C
TK82C was a Sinclair ZX81 clone made by Microdigital Eletrônica Ltda., a computer company located in Brazil. General information The TK82C had the Zilog Z80A processor running at 3.25 MHz, 2 KB SRAM and 8 KB of EPROM with the BASIC interpreter. The keyboard was made of layers of conductive (membrane) material and followed the Sinclair pattern. The video output was sent via a RF modulator to a TV set tuned at VHF channel 3, and it featured black characters on a white background. The maximum resolution was 64 x 44 pixels black and white, for graphic plotting. There were some special characters (shade patterns) useful for games and basic images. The TK82C included the SLOW function, which permitted the video be shown during the processing (the prior version, TK82, a Sinclair ZX80 clone, ran only in fast mode, so the image was not shown during its processing). In reality, the SLOW function was done by an add-on board that was factory-mounted over the main board. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ZX Spectrum
The ZX Spectrum () is an 8-bit computing, 8-bit home computer that was developed by Sinclair Research. It was released in the United Kingdom on 23 April 1982, and became Britain's best-selling microcomputer. Referred to during development as the ''ZX81 Colour'' and ''ZX82'', it was launched as the ''ZX Spectrum'' to highlight the machine's colour display, which differed from the black and white display of its predecessor, the ZX81. The Spectrum was released as six different models, ranging from the entry level with 16 Kilobyte, KB RAM released in 1982 to the ZX Spectrum +3 with 128 KB RAM and built in floppy disk drive in 1987; altogether they sold over 5 million units worldwide (not counting List of ZX Spectrum clones, unofficial clones). The Spectrum was among the first home computers in the United Kingdom aimed at a mainstream audience, and it thus had similar significance to the Commodore 64 in the US and the Thomson MO5 in France. The introduction of the ZX Spect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bipolar Junction Transistor
A bipolar junction transistor (BJT) is a type of transistor that uses both electrons and electron holes as charge carriers. In contrast, a unipolar transistor, such as a field-effect transistor, uses only one kind of charge carrier. A bipolar transistor allows a small current injected at one of its terminals to control a much larger current flowing between the terminals, making the device capable of amplification or switching. BJTs use two p–n junctions between two semiconductor types, n-type and p-type, which are regions in a single crystal of material. The junctions can be made in several different ways, such as changing the doping of the semiconductor material as it is grown, by depositing metal pellets to form alloy junctions, or by such methods as diffusion of n-type and p-type doping substances into the crystal. The superior predictability and performance of junction transistors quickly displaced the original point-contact transistor. Diffused transistors, along wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mikie
''Mikie'', known as in Japan, is an arcade video game developed and released by Konami in 1984. The object of the game is to guide a student named Mikie around the school locations to collect hearts which make up a letter from his girlfriend while being chased by members of the school staff. In Japan, the game's setting was changed to an office in order to avoid controversy, while the original version of the game was released internationally. Centuri distributed the game in North America. Gameplay The game starts at the classroom where Toru Mikie (美紀 徹, Miki Tōru) gets out of his seat for the player to begin the game. Mikie must bump the students out of their seats to collect the hearts they're sitting on, while simultaneously avoiding the classroom teacher. Once all hearts are collected by the player he is allowed to leave the room and enter the school corridor. The school corridor is where Mikie will be chased by the janitor and his classroom teacher, who follows him o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore Plus4
The Commodore Plus/4 is a home computer released by Commodore International in 1984. The "Plus/4" name refers to the four-application ROM resident office suite (word processor, spreadsheet, database, and graphing); it was billed as "the productivity computer with software built-in." Internally, the Plus/4 shared the same basic architecture as the lower-end Commodore 16 and 116 models, and was able to use software and peripherals designed for them. The Plus/4 was incompatible with the Commodore 64's software and some of its hardware. Although the Commodore 64 was more established, the Plus/4 was aimed at the more business oriented part of the personal computer market. History In the early 1980s, Commodore found itself engaged in a price war in the home computer market. Companies like Texas Instruments and Timex Corporation were releasing computers that undercut the price of Commodore's PET line. Commodore's MOS Technology division had designed a video chip but could not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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