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Datasette
The third, most common version of the 1530 C2N Datassette The Commodore 1530 (C2N) Datasette, later also Datassette (a portmanteau of ''data'' and ''cassette''), is Commodore's dedicated magnetic tape data storage device. Using compact cassettes as the storage medium, it provides inexpensive storage to Commodore's 8-bit home/personal computers, notably the PET, VIC-20, and C64. A physically similar model, Commodore 1531, was made for the Commodore 16 and Plus/4 series computers. Features Typical compact cassette interfaces of the late 1970s use a small controller in the computer to convert digital data to and from analog tones. The interface is then connected to the cassette deck using normal audio cables like RCA jacks or 3.5mm phone jacks. This sort of system was used on the Apple II and TRS-80 Color Computer, as well as many S-100 bus systems, and allow them to be used with any cassette player with suitable connections. left, The Datasette loading process In the Data ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore 64
The Commodore 64, also known as the C64, is an 8-bit home computer introduced in January 1982 by Commodore International (first shown at the Consumer Electronics Show, January 7–10, 1982, in Las Vegas). It has been listed in the Guinness World Records as the highest-selling single computer model of all time, with independent estimates placing the number sold between 12.5 and 17 million units. Volume production started in early 1982, marketing in August for . Preceded by the VIC-20 and Commodore PET, the C64 took its name from its of RAM. With support for multicolor sprites and a custom chip for waveform generation, the C64 could create superior visuals and audio compared to systems without such custom hardware. The C64 dominated the low-end computer market (except in the UK and Japan, lasting only about six months in Japan) for most of the later years of the 1980s. For a substantial period (1983–1986), the C64 had between 30% and 40% share of the US market and two mil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore VIC-20
The VIC-20 (known as the VC-20 in Germany and the VIC-1001 in Japan) is an 8-bit home computer that was sold by Commodore Business Machines. The VIC-20 was announced in 1980, roughly three years after Commodore's first personal computer, the PET. The VIC-20 was the first computer of any description to sell one million units. It was described as "one of the first anti-spectatorial, non-esoteric computers by design...no longer relegated to hobbyist/enthusiasts or those with money, the computer Commodore developed was the computer of the future." The VIC-20 was called ''VC-20'' in Germany because the pronunciation of ''VIC'' with a German accent sounds like the German expletives "fick" or "wichsen". The term ''VC'' was marketed as though it were an abbreviation of ''VolksComputer'' ("people's computer," similar to Volkswagen and Volksempfänger). History Origin and marketing The VIC-20 was intended to be more economical than the PET computer. It was equipped with 5 KB of st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore Plus/4
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 fin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compact Cassette
The Compact Cassette or Musicassette (MC), also commonly called the tape cassette, cassette tape, audio cassette, or simply tape or cassette, is an analog magnetic tape recording format for audio recording and playback. Invented by Lou Ottens and his team at the Dutch company Philips in 1963, Compact Cassettes come in two forms, either already containing content as a prerecorded cassette (''Musicassette''), or as a fully recordable "blank" cassette. Both forms have two sides and are reversible by the user. Although other tape cassette formats have also existed - for example the Microcassette - the generic term ''cassette tape'' is normally always used to refer to the Compact Cassette because of its ubiquity. Its uses have ranged from portable audio to home recording to data storage for early microcomputers; the Compact Cassette technology was originally designed for dictation machines, but improvements in fidelity led to it supplanting the stereo 8-track cartridge and reel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compact Cassette
The Compact Cassette or Musicassette (MC), also commonly called the tape cassette, cassette tape, audio cassette, or simply tape or cassette, is an analog magnetic tape recording format for audio recording and playback. Invented by Lou Ottens and his team at the Dutch company Philips in 1963, Compact Cassettes come in two forms, either already containing content as a prerecorded cassette (''Musicassette''), or as a fully recordable "blank" cassette. Both forms have two sides and are reversible by the user. Although other tape cassette formats have also existed - for example the Microcassette - the generic term ''cassette tape'' is normally always used to refer to the Compact Cassette because of its ubiquity. Its uses have ranged from portable audio to home recording to data storage for early microcomputers; the Compact Cassette technology was originally designed for dictation machines, but improvements in fidelity led to it supplanting the stereo 8-track cartridge and reel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore PET
The Commodore PET is a line of personal computers produced starting in 1977 by Commodore International. A single all-in-one case combines a MOS Technology 6502 microprocessor, Commodore BASIC in read-only memory, keyboard, monochrome monitor, and, in early models, a cassette deck. Development of the system began in 1976, and a prototype was demonstrated at the January 1977 Consumer Electronics Show. The name "PET" was suggested by Andre Souson after he saw the Pet Rock in Los Gatos, and stated they were going to make the "pet computer". It was backronymed to Personal Electronic Transactor. A series of problems delayed production versions until December 1977, by which time the TRS-80 and Apple II had already begun deliveries. ''Byte'' referred to the three machines collectively as the "1977 trinity". Following the initial PET 2001, the design was updated through a series of models with more memory, better keyboard, larger screen, and other modifications. The systems were a top ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore 16
The Commodore 16 is a home computer made by Commodore International with a 6502-compatible 7501 or 8501 CPU, released in 1984 and intended to be an entry-level computer to replace the VIC-20. A cost-reduced version, the Commodore 116, was mostly sold in Europe. The C16 and C116 belong to the same family as the higher-end Plus/4 and are internally very similar to it (albeit with less RAM – 16 KB rather than 64 KB – and lacking the Plus/4's user port and Three plus one software). Software is generally compatible among all three provided it can fit within the C16's smaller RAM and does not utilize the user port on the Plus/4. While the C16 was a failure on the US market, it enjoyed some success in certain European countries and Mexico. Intention The C16 was intended to compete with other sub-$100 computers from Timex Corporation, Mattel, and Texas Instruments (TI). Timex's and Mattel's computers were less expensive than the VIC-20, and although the VIC-20 of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore International
Commodore International (other names include Commodore International Limited) was an American home computer and electronics manufacturer founded by Jack Tramiel. Commodore International (CI), along with its subsidiary Commodore Business Machines (CBM), was a significant participant in the development of the home personal computer industry in the 1970s, 1980s and early 1990s. The company developed and marketed the world's best-selling computer, the Commodore 64 (1982), and released its Amiga computer line in July 1985. With quarterly sales ending 1983 of $ (equivalent to $ in ), Commodore was one of the world's largest personal computer manufacturers. History Founding and early years Commodore co-founders Jack Tramiel and Manfred Kapp met in the early 1950s while both employed by the Ace Typewriter Repair Company in New York City. In 1954, they formed a partnership to sell used and reconditioned typewriters and used their profits to purchase the Singer Typewriter Company. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Tape Data Storage
Magnetic-tape data storage is a system for storing digital information on magnetic tape using digital recording. Tape was an important medium for primary data storage in early computers, typically using large open reels of IBM 7 track, 7-track, later 9-track tape, 9-track tape. Modern magnetic tape is most commonly packaged in cartridges and cassettes, such as the widely supported Linear Tape-Open (LTO) and IBM 3592 series. The device that performs the writing or reading of data is called a tape drive. Autoloader (data storage device), Autoloaders and tape library, tape libraries are often used to automate cartridge handling and exchange. Compatibility was important to enable transferring data. Tape data storage is now used more for system backup, data archive and data exchange. The low cost of tape has kept it viable for long-term storage and archive. Open reels Initially, magnetic tape for data storage was wound on reels. This standard for large computer systems persis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Square Wave
A square wave is a non-sinusoidal periodic waveform in which the amplitude alternates at a steady frequency between fixed minimum and maximum values, with the same duration at minimum and maximum. In an ideal square wave, the transitions between minimum and maximum are instantaneous. The square wave is a special case of a pulse wave which allows arbitrary durations at minimum and maximum amplitudes. The ratio of the high period to the total period of a pulse wave is called the duty cycle. A true square wave has a 50% duty cycle (equal high and low periods). Square waves are often encountered in electronics and signal processing, particularly digital electronics and digital signal processing. Its stochastic counterpart is a two-state trajectory. Origin and uses Square waves are universally encountered in digital switching circuits and are naturally generated by binary (two-level) logic devices. Square waves are typically generated by metal–oxide–semiconductor fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parity Bit
A parity bit, or check bit, is a bit added to a string of binary code. Parity bits are a simple form of error detecting code. Parity bits are generally applied to the smallest units of a communication protocol, typically 8-bit octets (bytes), although they can also be applied separately to an entire message string of bits. The parity bit ensures that the total number of 1-bits in the string is even or odd. Accordingly, there are two variants of parity bits: even parity bit and odd parity bit. In the case of even parity, for a given set of bits, the bits whose value is 1 are counted. If that count is odd, the parity bit value is set to 1, making the total count of occurrences of 1s in the whole set (including the parity bit) an even number. If the count of 1s in a given set of bits is already even, the parity bit's value is 0. In the case of odd parity, the coding is reversed. For a given set of bits, if the count of bits with a value of 1 is even, the parity bit value is se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Error Correction
In information theory and coding theory with applications in computer science and telecommunication, error detection and correction (EDAC) or error control are techniques that enable reliable delivery of digital data over unreliable communication channels. Many communication channels are subject to channel noise, and thus errors may be introduced during transmission from the source to a receiver. Error detection techniques allow detecting such errors, while error correction enables reconstruction of the original data in many cases. Definitions ''Error detection'' is the detection of errors caused by noise or other impairments during transmission from the transmitter to the receiver. ''Error correction'' is the detection of errors and reconstruction of the original, error-free data. History In classical antiquity, copyists of the Hebrew Bible were paid for their work according to the number of stichs (lines of verse). As the prose books of the Bible were hardly ever wr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
