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Western Digital WD2793
The FD1771, sometimes WD1771, is the first in a line of floppy disk controllers produced by Western Digital. It uses single density FM encoding introduced in the IBM 3740. It is packaged in a 40-pin DIP."The FD1771 is a single-chip floppy disk formatter/controller that interfaces with most available disk drives and virtually all types of computers." The FD1771 was announced on July 19, 1976, and sold for $60 each in lots of 100. Later models in the series added support for MFM encoding and increasingly added onboard circuitry that formerly had to be implemented in external components. Originally packaged as 40-pin dual in-line package (DIP) format, later models moved to a 28-pin format that further lowered implementation costs. Derivatives The FD1771 was succeeded by many derivatives that were mostly software-compatible: *The FD1781 was designed for double density, but required external modulation and demodulation circuitry, so it could support MFM, M2FM, GCR or other dou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FD1771 FDC Datasheet
The FD1771, sometimes WD1771, is the first in a line of floppy disk controllers produced by Western Digital. It uses single density FM encoding introduced in the IBM 3740. It is packaged in a 40-pin DIP."The FD1771 is a single-chip floppy disk formatter/controller that interfaces with most available disk drives and virtually all types of computers." The FD1771 was announced on July 19, 1976, and sold for $60 each in lots of 100. Later models in the series added support for MFM encoding and increasingly added onboard circuitry that formerly had to be implemented in external components. Originally packaged as 40-pin dual in-line package (DIP) format, later models moved to a 28-pin format that further lowered implementation costs. Derivatives The FD1771 was succeeded by many derivatives that were mostly software-compatible: *The FD1781 was designed for double density, but required external modulation and demodulation circuitry, so it could support MFM, M2FM, GCR or other dou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voltage-controlled Oscillator
A microwave (12–18GHz) voltage-controlled oscillator A voltage-controlled oscillator (VCO) is an electronic oscillator whose oscillation frequency is controlled by a voltage input. The applied input voltage determines the instantaneous oscillation frequency. Consequently, a VCO can be used for frequency modulation (FM) or phase modulation (PM) by applying a modulating signal to the control input. A VCO is also an integral part of a phase-locked loop. VCOs are used in synthesizers to generate a waveform whose pitch can be adjusted by a voltage determined by a musical keyboard or other input. A voltage-to-frequency converter (VFC) is a special type of VCO designed to be very linear in frequency control over a wide range of input control voltages. Types VCOs can be generally categorized into two groups based on the type of waveform produced. * ''Linear'' or '' harmonic oscillators'' generate a sinusoidal waveform. Harmonic oscillators in electronics usually consist of a re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore 1571
The Commodore 1571 is Commodore's high-end 5¼" floppy disk drive, announced in the summer of 1985. With its double-sided drive mechanism, it has the ability to use double-sided, double-density (DS/DD) floppy disks, storing a total of 360 kB per floppy. It also implemented a "burst mode" that doubled transfer speeds, helping address the very slow performance of previous Commodore drives. Earlier Commodore drives used a custom group coded recording format that stored 170 kB per side of a disk. This made it fairly competitive in terms of storage, but limited it to only reading and writing disks from other Commodore machines. The 1571 was designed to partner with the new Commodore 128 (C128), which introduced support for CP/M. Adding double-density MFM encoding allowed the drive to read and write contemporary CP/M disks (and many others). In contrast to its single-sided predecessors, the 1541 and the briefly-available 1570, the 1571 can use both sides of the disk a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinclair ZX Spectrum
The ZX Spectrum () is an 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 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 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 Spectrum led to a boom in companies producing software an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DISCiPLE
A disciple is a follower and student of a mentor, teacher, or other figure. It can refer to: Religion * Disciple (Christianity), a student of Jesus Christ * Twelve Apostles of Jesus, sometimes called the Twelve Disciples * Seventy disciples in the Gospel of Luke * Christian Church (Disciples of Christ), a Protestant denomination in North America descended from the Campbell movement * Disciples of Christ (Campbell Movement), a Christian group that arose during the Second Great Awakening * Disciples of `Abdu'l-Bahá, 19 Western Bahá'ís * The ten principal disciples of Buddha * Disciples of Confucius * Disciples of Jesus in Islam * Student of Kriya Yoga, of direct lineage to Mahavatar Babaji * Sahabah, the disciples of Muhammad * Follower of Paramahansa Yogananda * Śishya, the disciple in the Guru–shishya tradition of Hinduism * ''Śrāvaka'' (Sanskrit) or ''savaka'' (Pali), disciples in Buddhism and Jainism * Tarmida ('disciple'), a junior priest in Mandaeism Books, games, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SAM Coupé
Sam, SAM or variants may refer to: Places * Sam, Benin * Sam, Boulkiemdé, Burkina Faso * Sam, Bourzanga, Burkina Faso * Sam, Kongoussi, Burkina Faso * Sam, Iran * Sam, Teton County, Idaho, United States, a populated place People and fictional characters * Sam (given name), a list of people and fictional characters with the given name or nickname * Sam (surname), a list of people with the surname ** Cen (surname) (岑), romanized "Sam" in Cantonese ** Shen (surname) (沈), often romanized "Sam" in Cantonese and other languages Religious or legendary figures * Sam (Book of Mormon), elder brother of Nephi * Sām, a Persian mythical folk hero * Sam Ziwa, an uthra (angel or celestial being) in Mandaeism Animals * Sam (army dog) (died 2000) * Sam (horse) (b 1815), British Thoroughbred * Sam (koala) (died 2009), rescued after 2009 bush fires in Victoria, Australia * Sam (orangutan), in the movie ''Dunston Checks In'' * Sam (ugly dog) (1990–2005), voted the world's ugliest dog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acorn Archimedes
Acorn Archimedes is a family of personal computers designed by Acorn Computers of Cambridge, Cambridge, England. The systems are based on Acorn's own ARM architecture processors and the proprietary operating systems Arthur and RISC OS. The first models were introduced in 1987, and systems in the Archimedes family were sold until the mid-1990s. ARM's Reduced instruction set computer, RISC design, a 32-bit CPU (using 26-bit addressing), running at 8 Hertz, MHz, was stated as achieving 4.5+ Million instructions per second, MIPS, which provided a significant upgrade from 8-bit home computers, such as Acorn's previous machines. Claims of being the fastest micro in the world and running at 18 MIPS were also made during tests. Two of the first models—the A305 and A310—were given the BBC branding, with BBC Worldwide, BBC Enterprises regarding the machines as "a continuing part of the original computer literacy project". Dissatisfaction with the branding arrangement was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atari ST
The Atari ST is a line of personal computers from Atari Corporation and the successor to the Atari 8-bit family. The initial model, the Atari 520ST, had limited release in April–June 1985 and was widely available in July. It was the first personal computer with a bitmapped color GUI, using a version of Digital Research's GEM (desktop environment), GEM from February 1985. The Atari 1040ST, released in 1986 with 1 MB of RAM, was the first home computer with a cost-per-kilobyte of less than US$1. "ST" officially stands for "Sixteen/Thirty-two", referring to the Motorola 68000's 16-bit computing, 16-bit external bus and 32-bit computing, 32-bit internals. The system was designed by a small team led by Shiraz Shivji. Alongside the Macintosh, Amiga, Apple IIGS, and Acorn Archimedes, the ST is part of a mid-1980s generation of computers with 16- or 32-bit processors, 256 Kilobyte, KB or more of RAM, and computer mouse, mouse-controlled graphical user interfaces. The ST was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BBC Master
The BBC Master is a home computer released by Acorn Computers in early 1986. It was designed and built for the BBC, British Broadcasting Corporation (BBC) and was the successor to the BBC Micro, BBC Micro Model B. The Master 128 remained in production until 1993. Design The Master series featured several improvements on preceding BBC Micro models. The systems had RAM as standard, alleviating the shortage of available RAM which had amongst other things discouraged use of the best graphics modes in the original design. The Master 128 and its variants had two cartridge slots mounted behind the new numerical keypad, these employing sockets that provided a superset of the Acorn Electron Acorn Electron#Acorn Plus 1, Plus 1 cartridge interface capabilities, supporting the use of physically compatible Electron cartridges, but also supporting enhanced electrical characteristics for some of the cartridge connector pins. Rather than the MOS Technology 6502 Central processing unit, micropro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acorn Electron
The Acorn Electron (nicknamed the Elk inside Acorn and beyond) was a lower-cost alternative to the BBC Micro educational/ home computer, also developed by Acorn Computers Ltd, to provide many of the features of that more expensive machine at a price more competitive with that of the ZX Spectrum. It had 32 kilobytes of RAM, and its ROM included BBC BASIC II together with the operating system. Announced in 1982 for a possible release the same year, it was eventually introduced on 25 August 1983 priced at £199. The Electron was able to save and load programs onto audio cassette via a supplied cable that connected it to any standard tape recorder that had the correct sockets. It was capable of bitmapped graphics, and could use either a television set, a colour (RGB) monitor or a monochrome monitor as its display. Several expansions were made available to provide many of the capabilities omitted from the BBC Micro. Acorn introduced a general-purpose expansion unit, the Plus 1, off ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRS-80
The TRS-80 Micro Computer System (TRS-80, later renamed the Model I to distinguish it from successors) is a desktop microcomputer launched in 1977 and sold by Tandy Corporation through their Radio Shack stores. The name is an abbreviation of ''Tandy Radio Shack, Z80 icroprocessor'. It is one of the earliest mass-produced and mass-marketed retail home computers. The TRS-80 has a full-stroke QWERTY keyboard, the Zilog Z80 processor, 4 KB dynamic random-access memory (DRAM) standard memory, small size and desk area, floating-point Level I BASIC language interpreter in read-only memory (ROM), 64-character per line video monitor, and a starting price of US$600 (equivalent to US$ in ). A cassette tape drive for program storage was included in the original package. While the software environment was stable, the cassette load/save process combined with keyboard bounce issues and a troublesome Expansion Interface contributed to the Model I's reputation as not well-suited to serious ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microcomputer
A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PCB). Microcomputers became popular in the 1970s and 1980s with the advent of increasingly powerful microprocessors. The predecessors to these computers, mainframes and minicomputers, were comparatively much larger and more expensive (though indeed present-day mainframes such as the IBM System z machines use one or more custom microprocessors as their CPUs). Many microcomputers (when equipped with a keyboard and screen for input and output) are also personal computers (in the generic sense). An early use of the term ''personal computer'' in 1962 predates microprocessor-based designs. ''(See "Personal Computer: Computers at Companies" reference below)''. A ''microcomputer'' used as an embedded control system may have no human-readable input ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
