Home computer

From Wikipedia, the free encyclopedia - View original article

Jump to: navigation, search
Children playing Paperboy on an Amstrad CPC 464 in the 1980s


Advertisements for early home computers were rife with possibilities for their practical use in the home, from cataloging recipes to personal finance to home automation,[3][4][5] but these were seldom realized in practice. For example, using a typical 1980s home computer as a home automation appliance would require the computer to be kept powered on at all times and dedicated to this task. Personal finance and database use required tedious data entry. By contrast, advertisements in the specialty computer press often simply listed specifications.[6][7] If no packaged software was available for a particular application, the home computer user was required to learn computer programming; a significant time commitment many new computer owners weren't willing to make. Still, for others the home computer offered the first opportunity to learn to program.[8]

Today the line between 'business' and 'home' computer market segments has blurred or vanished completely, since both categories of computers now typically use the same processor architectures, peripherals, operating systems, and applications. Often the only difference may be the sales outlet through which they are purchased. Another change from the home computer era is that the once-common endeavour of writing one's own software programs has almost vanished from home computer use.[9][10]


As early as 1965, some experimental projects such as Jim Sutherland's ECHO IV explored the possible utility of a computer in the home.[11][12] In 1969, the Honeywell Kitchen Computer was marketed as a luxury gift item, and would have inaugurated the era of home computing, but none were sold.[13]


While two early home computers (Sinclair ZX80, and Acorn Atom) could be bought either in kit form or assembled, most home computers were only sold pre-assembled. They were enclosed in plastic or metal cases similar in appearance to typewriter or hi-fi equipment enclosures, which were more familiar and attractive to consumers than the industrial metal card-cage enclosures used by the Altair and similar computers. The keyboard - a feature lacking on the Altair - was usually built into the same case as the motherboard. Ports for plug-in peripheral devices such as a video display, cassette tape recorders, joysticks, and (later) disk drives either were built-in or available on expansion cards. Although the Apple II series had internal expansion slots, most other home computer models' expansion arrangements were through externally-accessible 'expansion ports' that also served as a place to plug in cartridge-based games. Usually the manufacturer would sell peripheral devices designed to be compatible with their computers as extra cost accessories. Peripherals were not often interchangeable between different brands of home computer, or even between successive models of the same brand.

To save the cost of a dedicated monitor, the home computer often would connect through an RF modulator to the family TV set, which served as both video display and sound system.[15]

After the success of systems like the RadioShack TRS-80, the Commodore PET and the Apple II in 1977, large numbers of new machines of all types began to appear during the late 1970s and early 1980s. Some home computers sold many units over several years, such as the BBC Micro, Sinclair ZX Spectrum, Atari 800XL and Commodore 64, and attracted third-party software development. By 1982, an estimated 621,000 home computers were in use in the United States, at an average sales price of $530.[16]


Still, home computers competed in the same market as the consoles. A home computer was often seen as simply as a higher end purchase than a console, adding abilities to what would still be mainly a gaming device. A common marketing tactic was to show a computer system and console playing games side by side, then emphasising the computer's greater ability by showing it running user-created programs, education software, word processing, spreadsheet and other applications while the game console showed a blank screen or continued playing the same repetitive game.


Books of type-in program listings were available for most models of computer with titles along the lines of 64 Amazing BASIC Games for the Commodore 64.[19] While most of the programs in these books were short and simple games or demos, some titles such as Compute!'s SpeedScript series, contained productivity software that rivaled commercial packages. To avoid the tedious process of typing in a program listing from a book, these books would sometimes include a mail-in offer from the author to obtain the programs on disk or cassette for a few dollars. Before the Internet, and before most computer owners had a modem, books were a popular and low-cost means of software distribution. They also served a role in familiarizing new computer owners with the concepts of programming; some titles added suggested modifications to the program listings for the user to carry out. Modifying software to fit one's needs or be compatible with one's system was a skill every advanced computer owner was expected to have.[20]

During the peak years of the home computer market, scores of models were produced, usually with little or no thought given to compatibility between different manufacturers or even within product lines of the same manufacturer.[21] The concept of a computer platform did not exist, except for the Japanese MSX standard.[22] Price wars drove manufacturers such as Coleco, Mattel and Texas Instruments from the market, as they could no longer sustain development of what had become, for them, money-losing projects.

Things were different in the business world, where cost-conscious small business owners had been using CP/M running on Z-80 based computers from Osborne, Kaypro, Morrow Designs and a host of other manufacturers. For many of these businesses, the development of the microcomputer is what made computer systems affordable where they had not been before. Soon after its August 1981 introduction, the IBM Personal Computer would eventually become the standard platform used in business, due to the IBM name and the system's open architecture, which encouraged production of third-party clones. The 6502-based Apple II series had carved out a niche for itself in business, thanks to the industry's first killer app, VisiCalc. However the Apple II would quickly be displaced for office use by IBM PC compatibles running Lotus 1-2-3.[23] Apple Computer's 1984 release of the Apple Macintosh introduced the modern GUI to the market, which IBM-compatible computers would eventually adopt.[24] Throughout the 1980s, PCs spread through businesses like wildfire, leading, by the end of the decade, to sub-$1000 IBM PC XT-class white box machines, usually built in Asia and sold by US companies like PCs Limited.

The declining cost of IBM-compatibles on the one hand, and the greatly increased graphics, sound, and storage abilities of fourth generation video game consoles such as the Sega Genesis and Super Nintendo Entertainment System on the other, combined to cause the market segment for home computers to vanish by the early 1990s in the US. In Europe, the home computer remained a distinct presence for a few years more, with the Amiga and Atari ST lines being the dominant players, but today a computer bought for home use anywhere will be very similar to those used in offices — made by the same manufacturers, with compatible peripherals, operating systems, and application software.


A Commodore 64c system, showing the basic layout of a typical home computer system of the era. Pictured are the CPU/keyboard unit, floppy disk drive, and dedicated color monitor. Many systems also had a dot matrix printer for producing paper output.
Eastern Bloc computers were often significantly different in appearance from western computers. Pictured is a KC 85/3 with its keyboard placed on top, by VEB Mikroelektronik Mühlhausen released in 1986 and based on an East German Zilog Z80 clone.
The Soviet Elektronika BK0010-01 home computer was based on the К1801ВМ1 (Soviet LSI-11-compatible CPU) and shared architectural similarities with PDP-11.

Many home computers were superficially similar. Most had a keyboard integrated into the same case as the motherboard; sometimes a cheap-to-make membrane or chiclet keyboard in the early days, although full-travel keyboards quickly became universal due to overwhelming consumer preference. Most systems could use an RF modulator to display 20–40 column text output on a home television. Indeed, the use of a television set as a display almost defines the pre-PC home computer. Although dedicated composite or "green screen" computer displays were available for this market segment and offered sharper text display and sometimes increased graphics resolution, a monitor was often a later purchase made only after users had bought a floppy disk drive, printer, modem, and the other pieces of a full system. This "peripherals sold separately" approach is another defining characteristic of the home computer era. Many first time computer buyers brought a base C-64 system home and hooked it up to their TV only to find they needed to buy a compatible disk drive (the Commodore 1541 was the only fully compatible model) or Datassette before they could make use of it as anything but a game machine.

In the early part of the 1980s, the dominant microprocessors used in home computers were the 8-bit MOS Technology 6502 (Apple, Commodore, Atari) and Zilog Z80 (TRS-80). One exception was the TI-99 series, announced in 1979 with a 16-bit TMS9900 CPU.[25]

Processor clock rates were typically 1–2 MHz for 6502 based CPU's and 2–4 MHz for Z80 based systems (yielding roughly equal performance), but this aspect was not emphasized by users or manufacturers, as the systems' limited RAM capacity, graphics abilities and storage options had a more perceivable effect on performance than CPU speed. Clock rate was considered a technical detail of interest only to users needing accurate timing for their own programs. To economize on component cost, often the same crystal used to produce color television compatible signals was also divided down and used for the processor clock. This meant processors rarely operated at their full rated speed, and had the side-effect that European and North American versions of the same home computer operated at slightly different speeds and different video resolution due to different television standards.

Initially, many home computers used the then-ubiquitous compact audio cassette as a storage mechanism. A rough analogy to how this worked would be to place a recorder on the phone line as a file was uploaded by modem to "save" it, and playing the recording back through the modem to "load". Most cassette implementations were notoriously slow and unreliable, but early 8 inch floppy disk drives as found on more costly business-oriented microcomputers were large and prohibitively expensive. Smaller and cheaper[26] 5.25" form factor drives gained popularity, then mass production decreased prices still further. 5.25" floppy disk drives would remain standard until the end of the 8-bit era. Though external 3.5" drives were made available for home computer systems toward the latter part of the 1980s, most software sold for 8-bit home computers remained on 5.25" disks; 3.5" drives were used for data storage. Standardization of disk formats was not common; sometimes even different models from the same manufacturer used different disk formats. Toward the end of the home computer era, drives for a number of home computer models appeared offering disk-format compatibility with the IBM PC. The disk drives sold with the Commodore 128, Amiga and Atari ST were all able to read and write PC disks, which themselves were undergoing the transition from 5.25" to 3.5" format at the time.

Various copy protection schemes were developed for floppy disks; most were broken in short order. Many users would only tolerate copy protection for games, as wear and tear on disks was a significant issue in an entirely floppy-based system. The ability to make a "working backup" disk of vital application software was seen as important. Copy programs that advertised their ability to copy or even remove common protection schemes were a common category of utility software in this pre-DMCA era.

In another defining characteristic of the home computer, instead of a command line, the BASIC interpreter served double duty as a user interface. Coupled to a character-based screen or line editor, BASIC's file management commands could be entered in direct mode. In contrast to modern computers, home computers most often had their operating system (OS) stored in ROM chips. This made startup times very fast — no more than a few seconds — but made OS upgrades difficult or impossible without buying a new unit. Usually only the most severe bugs were fixed by issuing new ROMs to replace the old ones at the user's cost. Although modern operating systems include extensive programming libraries to ease development and promote standardization, home computer operating systems provided little support to application programs. However, software often switched out the ROM based OS completely to free the address space it occupied and maximize RAM capacity, accessing hardware directly to perform a specific task. As multitasking was never common on home computers, this practice wasn't much of a liability.

In an enduring reflection of their early cassette-oriented nature, most home computers loaded their disk operating system (DOS) separately from the main OS. The DOS was only used to send commands to the floppy disk drive and was not required to perform other computing functions. One exception was Commodore, whose DOS was not loaded into the computer's main memory at all — its disk drives contained a 6502 processor and Commodore DOS in ROM.

Many home computers had a cartridge interface which accepted ROM-based software. This was also used for expansion or upgrades such as fast loaders. Application software on cartridge did exist, and eliminated the need for disk swapping on single drive systems, but the vast majority of cartridges were games.[27]

From about 1985, the high end of the home computer market began to be dominated by "next generation" home computers using the 16-bit Motorola 68000 chip, which enabled the greatly increased abilities of the Amiga and Atari ST series. Graphics resolutions approximately doubled, and color palettes increased from dozens to hundreds or thousands of colors available. Stereo sound became standard for the first time. Clock rates on these systems were approximately 8 MHz with RAM capacities of 256 kB (for the base Amiga 1000 system) up to 1024 kB (1 megabyte, a milestone, first seen on the Atari 1040ST). These systems used 3.5" floppy disks from the beginning but 5.25" drives were made available to facilitate data exchange with IBM PC compatibles. The Amiga and ST both had GUIs inspired by the Apple Macintosh, but at a list price of $2495 (over $5000 in 2007 dollars), the Macintosh itself was too expensive for most households.

Radio frequency interference[edit]

After the first wave of computers landed in American homes, the United States Federal Communications Commission (FCC) began receiving complaints of electromagnetic interference to television reception. By 1979 the FCC demanded that home computer makers submit samples for radio frequency interference testing. It was found that "first generation" home computers emitted too much radio frequency noise for household use. Between 1980 and 1982 regulations governing RF emittance from home computers were phased in.[28] Some companies appealed to the FCC to waive the requirements for home computers, while others (with compliant designs) objected to the waiver. Eventually techniques to suppress interference became standardized.[29]

The Home Computer "Revolution"[edit]

In the late 1970s and early 1980s, from about 1977 to 1983, it was widely predicted [30] that computers would soon revolutionize many aspects of home and family life as they had business practices in the previous decades.[31] Mothers would keep their recipe catalog in "kitchen computer" databases and turn to a medical database for help with child care, fathers would use the family's computer to manage family finances and track automobile maintenance. Children would use disk-based encyclopedias for school work and would be avid video gamers. Home automation would bring about the intelligent home of the '80s. Using Videotex, NAPLPS or some sort of as-yet unrealized computer technology, television would gain interactivity. It would be possible to do the week's grocery shopping through the television.[32] The "personalized newspaper" (to be displayed on the television screen) was another commonly-predicted application.[33] Morning coffee would be brewed automatically under computer control.[34][35] The same household computer would control the home's lighting and temperature. Robots would take the garbage out, and be programmed to perform new tasks via the home computer. Electronics were expensive, so it was generally assumed that each home would have only one computer for the entire family to use.[36] Home control would be performed in a multitasking timesharing arrangement, with interfaces to the various devices it was expected to control.

When the computer revolution was unofficially announced in the early 1980s, all indications were that it would change the world. Experts predicted that within five years, every household would have a computer. Dad would run his business on it. Mom would store her recipes on it. The kids would do their homework on it. Today only 15% of American homes have a computer — and the other 85% don't seem the least bit interested. There is a general feeling that the home computer was a fad and that there is really no practical purpose for a computer in the home.[37]

Commodore Magazine, September 1987 edition

All this was predicted to be commonplace sometime before the end of the decade, but by 1987 the predicted revolution was said to be "in shambles", with only 15% of American homes owning a computer.[38] Virtually every aspect that was foreseen would be delayed to later years or would be entirely surpassed by later technological developments. The home computers of the early 1980s could not multitask.[39] Even if they could, other technical limitations predominated; memory capacities were too small to hold entire encyclopedias or databases of financial records;[40] floppy disk-based storage was inadequate in both capacity and speed for multimedia work;[41] and the home computers' graphics chips could only display blocky, unrealistic images and blurry, jagged text that would be difficult to read a newspaper from.[42] Although CD-ROM technology was introduced in 1985 with much promise for their future use, the drives were prohibitively expensive and only interfaced with IBM PCs and compatibles.[43][44][45]

Before long, a backlash set in—computer users were "geeks", "nerds" or worse, "hackers" The North American video game crash of 1983 soured many on home computer technology as users saw large investments in 'the technology of the future' turn into dead-ends when manufacturers pulled out of the market or went out of business. The computers that were bought for use in the family room were either forgotten in closets or relegated to basements and children's bedrooms to be used exclusively for games and the occasional book report. Home computers of the 1980s have been called "a technology in search of a use".[46] A 1985 study found that, during a typical week, 40% of adult computer owners did not use their computers at all. Usage rates among children were higher, with households reporting that only 16-20% of children aged 6–17 did not use the computer during a typical week.[47] In 1977, referring to computers used in home automation at the dawn of the home computer era, Digital Equipment Corporation CEO Ken Olsen is quoted as saying "There is no reason for any individual to have a computer in his home."[48]

It would take another 10 years for technology to mature, for the graphical user interface to make the computer approachable for non-technical users, and for the internet to provide a compelling reason for most people to want a computer in their homes. Separate 1998 studies found that 75% of Americans with Internet access accessed primarily from home and that not having Internet access at home inhibited Internet use.[47] Predicted aspects of the revolution were left by the wayside or modified in the face of an emerging reality. The cost of electronics dropped precipitously and today many families have a computer for each family member, or a laptop for mom's active lifestyle, a desktop for dad with the kids sharing a computer. Encyclopedias, recipe catalogs and medical databases are kept online and accessed over the world wide web — not stored locally on floppy disks or CD-ROM. TV has yet to gain substantial interactivity; instead, the web has evolved alongside television, giving rise to the second screen concept. The HTPC and services like Netflix, Google TV or Apple TV along with internet video sites such as YouTube and Hulu may one day replace traditional broadcast and cable television. Our coffee may be brewed automatically every morning, but the computer is a simple one embedded in the coffee maker, not under external control. As of 2008, robots are just beginning to make an impact in the home, with Roomba and Aibo leading the charge.

This delay wasn't out of keeping with other technologies newly introduced to an unprepared public. Early motorists were widely derided with the cry of "Get a horse!"[49] until the automobile was accepted. Television languished in research labs for decades before regular public broadcasts began. In an example of changing applications for technology, before the invention of radio, the telephone was used to distribute opera and news reports, whose subscribers were denounced as "illiterate, blind, bedridden and incurably lazy people".[50] Likewise, the acceptance of computers into daily life today is a product of continuing refinement of both technology and perception.

Use in the 21st Century[edit]

As older computer hardware ages and the supply of replacement parts dwindles, it has become popular among enthusiasts[51] to emulate these machines, recreating their environments[52] on modern hardware. One of the more well-known emulators is the Multiple Emulator Super System which can emulate most of the better-known home computers. A more or less complete list of home computer emulators can be found in the List of computer system emulators article. Games for many 8 and 16 bit home computers are becoming available for the Wii Virtual Console.

Retrocomputing is the use of real hardware to perform modern tasks such as surfing the web and email. Throughout the 1990s and 1st decade of the 21st century, many home computer systems were available inexpensively at garage sales and on eBay. Many enthusiasts have started to collect home computers, with older and rarer systems being much sought after. Sometimes the collections turn into a virtual museum presented on web sites.[53] The Commodore 64 has been repackaged as the C-One and C64 Direct-to-TV, both designed by Jeri Ellsworth with modern enhancements.[54]

Notable home computers[edit]

The 1977 Apple II with 2 Disk II disk drives and an Apple monitor

The time line below describes many of the most popular or significant home computers of the late 1970s and of the 1980s.

The most popular home computers in the USA up to 1985 were: the TRS-80 (1977), various models of the Apple II family (first introduced in 1977), the Atari 400/800 (1979) along with its follow up models the 800XL and 130XE, and the Commodore VIC-20 (1980) and the Commodore 64 (1982). The VIC was the first computer of any type to sell over one million units, and the 64 is still the highest-selling single model of personal computer ever, with over 17 million produced before production stopped in 1994 – a 12-year run with only minor changes.[55]

In Europe the situation was slightly different, as many of the British made systems like Sinclair's ZX81 and Spectrum, and later the Amstrad/Schneider CPC were much cheaper in Europe than US systems (such as the Atari and Apple models). The reverse was also true, as popular British systems like the Spectrum never became popular in the US. A few British Sinclair models were sold for low prices in the US by Timex Corporation, such as the Timex Sinclair 1000 and the ill-fated Timex Sinclair 2068, but never established a strong following. The result was that these British systems were much more popular in Europe than in the USA, the only notable exception being the Commodore 64 (C64), which competed favorably price-wise with the British systems, and was the most popular system in Europe as in the USA.[56][57]

Until the introduction of the IBM PC in 1981, computers such as the Apple II and TRS 80 also found considerable use in office work.[58][59] In 1983 IBM introduced the PCjr in an attempt to continue their business computer success in the home computer market, but incompatibilities between it and the standard PC kept users away.[60][61] The Commodore PET had a sizable presence in the North American education market until that was largely ceded to the Apple II as Commodore focused on the C-64's success in the mass retail market.[62]


Three microcomputers were the prototypes for what would later become the home computer market segment; but when introduced they sold as much to hobbyists and small businesses as to the home.

The following computers also introduced significant advancements to the home computer segment:


No computer has sold more units than the Commodore 64.[65]
The East German Robotron KC 85/1 was virtually not available for sale due to huge demand by industrial, educational, and military institutions.

See also[edit]


  1. ^ "IBM PC turns 25". "Several popular home computers existed before the 1981 IBM PC launch. But the regimented business world considered Apple, Commodore, and Radio Shack's Tandy products "toys."" 
  2. ^ "The Impact of Home Computer Use on Children’s Activities and Development". 
  3. ^ Video of old TV Ad for Atari Home computers[dead link] from YouTube
  4. ^ "Home computer ads". Wotsit.thingy.com. 2001-02-05. Retrieved 2013-04-09. 
  5. ^ More home computer TV ads
  6. ^ "May 1982 VIC-20 ad". 
  7. ^ "Franklin ACE2000 ad". 
  8. ^ CNN.com readers recall the life-changing Commodore 64 from CNN
  9. ^ Jeremy Reimer (December 2005). "Personal Computer Market Share: 1975-2004". Ars Technica. Retrieved 2008-02-13. [dead link]
  10. ^ David Brin. "Why Johnny can't code". Retrieved 2013-04-09. 
  11. ^ Spicer, Dag (2000-08-12). "Dag Spier,''If You Can't Stand the Coding, Stay Out of the Kitchen'', "Dr. Dobb's Journal'', August 12, 2000". Drdobbs.com. Retrieved 2013-04-09. 
  12. ^ "James Tomayko "Anecdotes: Electronic Computer for Home Operation, The First Home Computer"" (PDF). Retrieved 2013-04-09. 
  13. ^ http://jdh.oxfordjournals.org/content/23/2/163.full.pdf Paul Atkinson, The Curious Case of the Kitchen Computer: Products and Non-Products in Design History, from Journal of Design History, Vol. 23 No.2 doi:10.1093.jdh/epq010
  14. ^ The Altair 8800 used binary LEDs and switches, and came as a kit
  15. ^ Texas Instruments TI-99/4 computer: At the start, the TI99/4 could not offer an RF-modulator certified by United States Federal Communications Commission (FCC), and had to use an expensive modified TV instead
  16. ^ Gregory S. Blundell, Personal computers in the Eighties, BYTE January 1983, pp. 166-182
  17. ^ "Dictionary — Definition of Microsoft Basic". [dead link]
  18. ^ Beuscher, Dave (2010-10-03). "About the Expansion Module #3 for the Colecovision". Allgame.com. Retrieved 2013-04-09. 
  19. ^ "C64 Type-In Books". Archived from the original on 2012-07-22. [dead link]
  20. ^ "10 PRINT CHR$(205.5+RND(1)); : GOTO 10". 
  21. ^ "SYSTEMS RELEASED IN ~ 1982 ~". 
  22. ^ "about the history of the MSX standard". Msx.gnu-linux.net. Retrieved 2013-04-09. 
  23. ^ "VisiCalc and the Rise of the Apple II". lowendmac.com. Retrieved 2010-11-03. 
  25. ^ The TI99/4 was unique in using a 16 bit processor from Retrogaming Times, Issue 42, February 20th, 2001
  26. ^ Hall, Douglas V. (1983). Microprocessors and Digital Systems (2nd ed.). McGraw-Hill. pp. 153–154. ISBN 0-07-025552-0. 
  27. ^ List of TI99/4 cartridges, mostly games from OldComputers.net
  28. ^ "Introduction to EMC". 
  29. ^ TRS-80 the "Trash-80" from PC-History.org
  30. ^ The Computer Revolution from eNotes.com
  31. ^ The computer revolution from The Eighties Club
  32. ^ "Online Shopping in the 1980s US IEEE ‘Annals of the History of Computing.’ October-December 2011 edition, Vol 33 No4 p57-61. ISSN: 1058-6180". 
  33. ^ "How Newspapers Tried to Invent the Web". 
  34. ^ A Small World: Smart Houses and the Dream of the Perfect Day. 
  35. ^ "Livable New York Resource Manual: SMART HOMES (Home Automation)". 
  36. ^ "A 1980s Home Computer Family Celebration". 
  37. ^ Gutman, Dan (09 1987). "What happened to the computer revolution?". Commodore Magazine. Retrieved 2013-01-11. 
  38. ^ "What happened to the computer revolution?". Commodore Magazine. Sep 1987. 
  39. ^ "What is UNIX". 
  40. ^ "How Much Information?". 
  42. ^ "Reading from paper versus screens: a critical review of the empirical literature". 
  43. ^ InfoWorld Jan 20,1986. 
  44. ^ "IBM Personal Computing: The CD-ROMs Are Coming, Compute! magazine Feb. 1987". 
  45. ^ "New Technologies: The Converging Digital Universe, Compute! magazine, April 1986". "Although the initial purchase price of $1495 may keep initial sales out of the home market in volume, the price for CD-ROM technology is expected to drop quickly over the next couple of years." 
  46. ^ "1980s Home Coding the art of amateur programming". 
  47. ^ a b "National Science Foundation, Division of Science Resources Studies The Application and Implications of Information Technologies in the Home: Where are the Data and What Do They Say? Arlington, VA (NSF 01-313) [March 2001]". 
  48. ^ snopes.com Ken Olsen from Snopes.com
  49. ^ Horseless Classrooms[dead link] from the Hawaii Education & Research Network
  50. ^ Clement Ader from Beb's Old Phones
  51. ^ Reviving Old Computer Games[dead link] from xtrazone.com
  52. ^ Traffic Details for gametap.com from Alexa
  53. ^ "HCM: Links". 
  54. ^ Retro-Computing with FPGAs article from Slashdot
  55. ^ "number of C64s sold". Gamasutra.com. Retrieved 2013-04-09. 
  56. ^ 25th Anniversary of the Sinclair ZX Spectrum[dead link] from Slashdot
  57. ^ Format Wars: The Tech that should have Won from ArmchairArcade.com
  58. ^ Tandy TRS-80 catalog listing many business uses[dead link] (PDF)
  59. ^ ""VisiCalc was first released for the Apple II, which quickly became an invaluable tool for businesspeople - at least until IBM moved into the "personal computing" market in 1981."". Lowendmac.com. Retrieved 2013-04-09. 
  60. ^ "IBM PCjr". 
  61. ^ "IBM PCjr". 
  62. ^ administrator@commodore.ca. "Commodore Educational brochure". Commodore.ca. Retrieved 2013-04-09. 
  63. ^ Long, Tony (June 5, 2007). "June 5, 1977: From a Little Apple a Mighty Industry Grows". Wired. Archived from the original on May 28, 2009. Retrieved July 13, 2012. 
  64. ^ What's New (February 1978), "Commodore Ships First PET Computers", BYTE (Byte Publications) 3 (2): 190  Commodore press release. "The PET computer made its debut recently as the first 100 units were shipped to waiting customers in mid-October 1977."
  65. ^ Grandiose Price for a Modest PC from Wired

External links[edit]