Exatron Stringy Floppy
The Exatron Stringy Floppy is a continuous loop tape drive developed by Exatron. The company introduced an S-100 stringy floppy drive at the 1978 West Coast Computer Faire, a version for the Radio Shack TRS-80 in 1979. Exatron sold about 4,000 TRS-80 drives by August 1981 for $249.50 each, stating that it was "our best seller by far". The tape cartridge is about the size of a business card, but about 3⁄16 inch thick; the magnetic tape inside the cartridge is 1⁄16 inch wide. There is no single catalog of files; the tape loop only moves in one direction, so a file that starts behind the current location cannot be read until the drive searches the entire loop for it. The device is capable of writing random access data files. If a record being sought has been overshot the drive advances the tape until it loops around to the beginning and continues seeking from there. According to Embedded Systems magazine, the Exatron Stringy Floppy uses Manchester encoding, achieving 14K read-write speeds and the code controlling the device was developed by Li-Chen Wang, who wrote a Tiny BASIC, the basis for the TRS-80 Model I Level I BASIC.
In the July 1983 issue of Compute!'s Gazette the Exatron Stringy Floppy for the Commodore VIC-20 and the 64 was reviewed. Calling the peripheral "a viable alternative" to tape or disk, the magazine noted that "under ideal conditions, a Stringy Floppy can outperform a VIC-1540/1541 disk drive". Texas Instruments licensed the Stringy Floppy as the Waferdrive for its TI CC-40 computers. Exatron pitched the ESF as "The viable alternative"; the ESF was faster and more reliable than a data cassette, half the price of a floppy disk. Cartridges, or "wafers", were available with tape lengths ranging from 5 to 75 feet. Known data capacities/tape length are: 4 kB/5 feet, 16 kB/20 feet, 48 kB/50 feet, 64 kB/75 feet. One complete cycle through a 20-foot tape takes 55 to 65 seconds, depending on the number of files on it. ZX Microdrive Rotronics Wafadrive Exatron Stringy Floppy as described by Bill Fletcher Getting Files off Stringy Floppy Wafers for use in Emulators Advertisements Exatron Official Website
The ColecoVision is Coleco Industries' second-generation home video-game console, released in August 1982. The ColecoVision offered a closer experience to more powerful arcade game systems compared to competitors such as the Atari 2600, along with the means to expand the system's basic hardware; the initial catalog of twelve games included Nintendo's Donkey Kong as the pack-in cartridge, Sega's graphically impressive Zaxxon, some lesser known arcade titles that found a larger audience on the console, such as Lady Bug, Cosmic Avenger, Venture. 145 titles in total were published as ROM cartridges for the system between 1982 and 1984. The ColecoVision was discontinued in 1985. By Christmas of 1982, Coleco had sold more than 500,000 units, in part on the strength of its bundled game; the ColecoVision's main competitor was the less commercially successful Atari 5200, based on the older Atari 400/800 computer. The ColecoVision was distributed by CBS Electronics outside of North America, was branded the CBS ColecoVision.
In Europe the console was released in July 1983, nearly one year after the North American release. Sales passed 1 million in early 1983, before the video game crash of 1983. By the beginning of 1984, quarterly sales of the ColecoVision had decreased. Over the next 18 months, the Coleco company ramped down its video game division withdrawing from the video game market by the end of the summer of 1985; the ColecoVision was discontinued by October 1985. Total sales of the ColecoVision are uncertain but were in excess of 2 million units, due to the console continuing to sell modestly up until its discontinuation the following year; the video game crash of 1983 has been cited as the main cause of the ColecoVision's being discontinued less than three years after its launch. In 1983 Spectravideo announced the SV-603 ColecoVision Video Game Adapter for its SV-318 computer; the company stated that the $70 product allowed users to "enjoy the entire library of exciting ColecoVision video-game cartridges".
The main console unit consists of a 14×8×2-inch rectangular plastic case that houses the motherboard, with a cartridge slot on the right side and connectors for the external power supply and RF jack at the rear. The controllers connect into plugs in a recessed area on the top of the unit; the design of the controllers is similar to that of Mattel's Intellivision—the controller is rectangular and consists of a numeric keypad and a set of side buttons. In place of the circular control disc below the keypad, the Coleco controller has a short, 1.5-inch joystick. The keypad is designed to accept a thin plastic overlay; each ColecoVision console shipped with two controllers. All first-party cartridges and most third-party software titles feature a 12-second pause before presenting the game select screen; this delay results from an intentional loop in the console's BIOS to enable on-screen display of the ColecoVision brand. Companies like Parker Brothers and Micro Fun bypassed this loop, which necessitated embedding portions of the BIOS outside the delay loop, further reducing storage available to actual game programming.
CPU: NEC version of Zilog Z80A @ 3.58 MHz Video processor: Texas Instruments TMS9928A 256×192 pixel resolution 32 sprites on-screen at once, max 4 per horizontal line 15 colors + transparent Sound: Texas Instruments SN76489A PSG 3 tone generators 1 noise generator Video RAM: 16 KB RAM: 1 KB ROM: 8 KB Texas Instruments TMS4764 Mask ROM Storage: ROM Cartridge of 8, 16, 24 or 32 KB capacity. From its introduction, Coleco touted the ColecoVision's hardware expandability by highlighting the Expansion Module Interface on the front of the unit; these hardware expansion modules and accessories were sold separately. Expansion Module #1 makes the ColecoVision compatible with the industry-leading Atari 2600, with some exceptions. Functionally, this gave the ColecoVision the largest software library of any console of its day; the expansion module prompted legal action from Atari. Coleco and Atari settled out of court with Coleco becoming licensed under Atari's patents; the royalty based license applied to Coleco's Gemini game system, a clone of the 2600, but with combined joystick/paddle controllers.
Expansion Module # 2 is a driving controller. The gas pedal is a simple on/off switch, so many gamers used the second ColecoVision controller as a gear shift for more precise speed control. Although Coleco called the driving controller an expansion module, it plugs into the controller port, not the Expansion Module Interface; the driving controller is compatible with the games Destructor, Bump'n' Jump and The Dukes of Hazzard. Expansion Module #3 converts the ColecoVision into a full-fledged computer known as the Adam, complete with keyboard, digital data pack cassette drives and printer; the Roller Controller is a trackball that came packaged with a conversion of the arcade game Slither, a Centipede clone. The roller controller uses a special power connector, not compatible with Expansion Module #3. Coleco mailed an adapter to owners of both units; the other cartridge programmed to use the roller controller is Victory. A joystick mode switch on the roller controller allows it to be used with al
A microcomputer is a small inexpensive computer with a microprocessor as its central processing unit. It includes a microprocessor and minimal input/output circuitry mounted on a single printed circuit board. Microcomputers became popular in the 1970s and 1980s with the advent of powerful microprocessors; the predecessors to these computers and minicomputers, were comparatively much larger and more expensive. Many microcomputers are personal computers; the abbreviation micro was common during the 1970s and 1980s, but has now fallen out of common usage. The term microcomputer came into popular use after the introduction of the minicomputer, although Isaac Asimov used the term in his short story "The Dying Night" as early as 1956. Most notably, the microcomputer replaced the many separate components that made up the minicomputer's CPU with one integrated microprocessor chip; the French developers of the Micral N filed their patents with the term "Micro-ordinateur", a literal equivalent of "Microcomputer", to designate a solid state machine designed with a microprocessor.
In the USA, the earliest models such as the Altair 8800 were sold as kits to be assembled by the user, came with as little as 256 bytes of RAM, no input/output devices other than indicator lights and switches, useful as a proof of concept to demonstrate what such a simple device could do. However, as microprocessors and semiconductor memory became less expensive, microcomputers in turn grew cheaper and easier to use: Increasingly inexpensive logic chips such as the 7400 series allowed cheap dedicated circuitry for improved user interfaces such as keyboard input, instead of a row of switches to toggle bits one at a time. Use of audio cassettes for inexpensive data storage replaced manual re-entry of a program every time the device was powered on. Large cheap arrays of silicon logic gates in the form of read-only memory and EPROMs allowed utility programs and self-booting kernels to be stored within microcomputers; these stored programs could automatically load further more complex software from external storage devices without user intervention, to form an inexpensive turnkey system that does not require a computer expert to understand or to use the device.
Random access memory became cheap enough to afford dedicating 1-2 kilobytes of memory to a video display controller frame buffer, for a 40x25 or 80x25 text display or blocky color graphics on a common household television. This replaced the slow and expensive teletypewriter, common as an interface to minicomputers and mainframes. All these improvements in cost and usability resulted in an explosion in their popularity during the late 1970s and early 1980s. A large number of computer makers packaged microcomputers for use in small business applications. By 1979, many companies such as Cromemco, Processor Technology, IMSAI, North Star Computers, Southwest Technical Products Corporation, Ohio Scientific, Altos Computer Systems, Morrow Designs and others produced systems designed either for a resourceful end user or consulting firm to deliver business systems such as accounting, database management, word processing to small businesses; this allowed businesses unable to afford leasing of a minicomputer or time-sharing service the opportunity to automate business functions, without hiring a full-time staff to operate the computers.
A representative system of this era would have used an S100 bus, an 8-bit processor such as an Intel 8080 or Zilog Z80, either CP/M or MP/M operating system. The increasing availability and power of desktop computers for personal use attracted the attention of more software developers. In time, as the industry matured, the market for personal computers standardized around IBM PC compatibles running DOS, Windows. Modern desktop computers, video game consoles, tablet PCs, many types of handheld devices, including mobile phones, pocket calculators, industrial embedded systems, may all be considered examples of microcomputers according to the definition given above. Everyday use of the expression "microcomputer" has declined from the mid-1980s and has declined in commonplace usage since 2000; the term is most associated with the first wave of all-in-one 8-bit home computers and small business microcomputers. Although, or because, an diverse range of modern microprocessor-based devices fit the definition of "microcomputer", they are no longer referred to as such in everyday speech.
In common usage, "microcomputer" has been supplanted by the term "personal computer" or "PC", which specifies a computer, designed to be used by one individual at a time, a term first coined in 1959. IBM first promoted the term "personal computer" to differentiate themselves from other microcomputers called "home computers", IBM's own mainframes and minicomputers. However, following its release, the IBM PC itself was imitated, as well as the term; the component parts were available to producers and the BIOS was reverse engineered through cleanroom design techniques. IBM PC compatible "clones" became commonplace, the terms "personal computer", "PC", stuck with the general public specifically for a DOS or Windows-compatible computer. Monitors and other devices for inpu
The Coleco Adam is a home computer, expansion for the ColecoVision, released in 1983 by American toy and video game manufacturer Coleco. It was an attempt to follow on the success of the company's ColecoVision video game console; the Adam was not successful because of early production problems, was discontinued in early 1985. Coleco announced the Adam at the Summer Consumer Electronics Show in June 1983, executives predicted sales of 500,000 by Christmas 1983. From the time of the computer's introduction to the time of its shipment, the price increased, from USD $525 to $725; the Adam announcement received favorable press coverage. Competitors such as Commodore and Atari immediately announced similar computer-printer bundles; the company announced an extensive marketing campaign, with television commercials for "boys age 8 to 16 and their fathers... the two groups that fuel computer purchases", print advertisements in nontechnical publications like Time and People. The Boston Phoenix, observing that Adam's $600 price was comparable to the lowest price for a letter-quality printer alone, stated "a nice trick if they can do it!"
It was a trick. In June Coleco promised to ship the computer by August. In August it promised to ship a half million Adams by Christmas, but missed shipping dates of 1 September, 15 September, 1 October, 15 October. Ahoy! reported that Coleco had not shipped by early October because of various problems. Each month of delay could mean losing the opportunity to sell 100,000 units, the magazine reported, adding that missing the Christmas season would result in "inestimable losses". CEO Arnold Greenberg promised in late September to ship by "mid-October", but claimed that Adam was "not a Christmas item"; the printer was the main cause of the delays. Greenberg refused to say; the company did not ship review units to magazines planning to publish reviews before Christmas, stating that all were going to dealers, but admitted that it would not meet the company's goal of shipping 400,000 computers by the end of the year. Despite great consumer interest, Coleco shipped only 95,000 units by December, many of which were defective.
One store manager stated that five of six sold Adams had been returned, expected that the sixth would be returned after being opened on Christmas. Coleco partnered with Honeywell Information Systems to open up repair chain stores around the nation. By December 1983 the press reported that company executives at a news conference "fielded questions about Coleco's problems with its highly-publicized new Adam home computer, plagued by production delays and complaints of defects", with the company able to fulfill only one third of its Canadian orders for Christmas. Less than 10% of Adam units had defects, the company claimed, "well below industry standards". An analyst stated in early 1984 that the company had targeted a special area: home users who have students or teenage children who are writing term papers and who tend to be naive computer users. Coleco has tried to make the Adam easy to use and attractive to that group, consciously excluding other groups by the way that configured the machine.
By March 1984 John J. Anderson declared Adam as having caused for Coleco "a trail of broken promises, unfulfilled expectations, skittish stockholders." On January 2, 1985, after continuing complaints about Adam failures and low sales, Coleco announced that it was discontinuing the Adam and would be selling off its inventory. Coleco revealed that it lost $35 million in late 1983, along with a loss of $13.4 million in the first 9 months of 1984. Coleco did not reveal which company they were selling the inventory to, but stated that they had worked with this partner before. No final sales numbers were revealed of the Adam computer and Expansion, but one analyst estimated that Coleco had sold 350,000 Adams in 1983 and 1984. In its favor, the Adam had a large software library from the start, it was derived from and compatible with the ColecoVision's software and accessories, and, in addition, the popular CP/M operating system was available as an option. Its price gave a complete system: an 80 kB RAM computer, tape drive, letter-quality printer, software including the Buck Rogers: Planet of Zoom video game.
The IBM PCjr sold for $669 but included no peripherals, although the popular Commodore 64 sold for around $200, its price was not much lower after the purchase of a printer, tape or disk drive, software. Like many home computers of its day, the Adam was intended to use a television set for its display; the SmartWriter electronic typewriter loaded. In this mode, the system operated just like a typewriter, printing letters as soon as the user typed them. Pressing the Escape/WP key put SmartWriter into word processor mode, which functioned to a modern word processor. Unlike other home computers at the time, the Adam did not have its BASIC interpreter stored in ROM. Instead, it featured a built-in electronic typewriter and word processor, SmartWriter, as well as the Elementary Operating System OS kernel and the 8kB OS-7 ColecoVision operating system; the SmartBASIC interpreter was delivered on
An integrated circuit or monolithic integrated circuit is a set of electronic circuits on one small flat piece of semiconductor material, silicon. The integration of large numbers of tiny transistors into a small chip results in circuits that are orders of magnitude smaller and faster than those constructed of discrete electronic components; the IC's mass production capability and building-block approach to circuit design has ensured the rapid adoption of standardized ICs in place of designs using discrete transistors. ICs are now used in all electronic equipment and have revolutionized the world of electronics. Computers, mobile phones, other digital home appliances are now inextricable parts of the structure of modern societies, made possible by the small size and low cost of ICs. Integrated circuits were made practical by mid-20th-century technology advancements in semiconductor device fabrication. Since their origins in the 1960s, the size and capacity of chips have progressed enormously, driven by technical advances that fit more and more transistors on chips of the same size – a modern chip may have many billions of transistors in an area the size of a human fingernail.
These advances following Moore's law, make computer chips of today possess millions of times the capacity and thousands of times the speed of the computer chips of the early 1970s. ICs have two main advantages over discrete circuits: performance. Cost is low because the chips, with all their components, are printed as a unit by photolithography rather than being constructed one transistor at a time. Furthermore, packaged ICs use much less material than discrete circuits. Performance is high because the IC's components switch and consume comparatively little power because of their small size and close proximity; the main disadvantage of ICs is the high cost to fabricate the required photomasks. This high initial cost means. An integrated circuit is defined as: A circuit in which all or some of the circuit elements are inseparably associated and electrically interconnected so that it is considered to be indivisible for the purposes of construction and commerce. Circuits meeting this definition can be constructed using many different technologies, including thin-film transistors, thick-film technologies, or hybrid integrated circuits.
However, in general usage integrated circuit has come to refer to the single-piece circuit construction known as a monolithic integrated circuit. Arguably, the first examples of integrated circuits would include the Loewe 3NF. Although far from a monolithic construction, it meets the definition given above. Early developments of the integrated circuit go back to 1949, when German engineer Werner Jacobi filed a patent for an integrated-circuit-like semiconductor amplifying device showing five transistors on a common substrate in a 3-stage amplifier arrangement. Jacobi disclosed cheap hearing aids as typical industrial applications of his patent. An immediate commercial use of his patent has not been reported; the idea of the integrated circuit was conceived by Geoffrey Dummer, a radar scientist working for the Royal Radar Establishment of the British Ministry of Defence. Dummer presented the idea to the public at the Symposium on Progress in Quality Electronic Components in Washington, D. C. on 7 May 1952.
He gave many symposia publicly to propagate his ideas and unsuccessfully attempted to build such a circuit in 1956. A precursor idea to the IC was to create small ceramic squares, each containing a single miniaturized component. Components could be integrated and wired into a bidimensional or tridimensional compact grid; this idea, which seemed promising in 1957, was proposed to the US Army by Jack Kilby and led to the short-lived Micromodule Program. However, as the project was gaining momentum, Kilby came up with a new, revolutionary design: the IC. Newly employed by Texas Instruments, Kilby recorded his initial ideas concerning the integrated circuit in July 1958 demonstrating the first working integrated example on 12 September 1958. In his patent application of 6 February 1959, Kilby described his new device as "a body of semiconductor material … wherein all the components of the electronic circuit are integrated." The first customer for the new invention was the US Air Force. Kilby won the 2000 Nobel Prize in Physics for his part in the invention of the integrated circuit.
His work was named an IEEE Milestone in 2009. Half a year after Kilby, Robert Noyce at Fairchild Semiconductor developed a new variety of integrated circuit, more practical than Kilby's implementation. Noyce's design was made of silicon. Noyce credited Kurt Lehovec of Sprague Electric for the principle of p–n junction isolation, a key concept behind the IC; this isolation allows each transistor to operate independently despite being part of the same piece of silicon. Fairchild Semiconductor was home of the first silicon-gate IC technology with self-aligned gates, the basis of all modern CMOS integrated circuits; the technology was developed by Italian physicist Federico Faggin in 1968. In 1970, he joined Intel in order to develop the first single-chip central processing unit microprocessor, the Intel 4004, for which he received the National Medal of Technology and Innovation in 2010; the 4004 was designed by Busicom's Masatoshi Shima and Intel's Ted Hoff in 1969, but it was Faggin's improved design in 1970 that made it a reality.
Advances in IC technology smaller features and la