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154-666: 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, eventually reaching 2.5 million. It was described as "one of

308-409: A byte or word , is referred to, it is usually specified by a number from 0 upwards corresponding to its position within the byte or word. However, 0 can refer to either the most or least significant bit depending on the context. Similar to torque and energy in physics; information-theoretic information and data storage size have the same dimensionality of units of measurement , but there

462-493: A disk drive (the Commodore 1541 was the only fully-compatible model) or Datasette before they could make use of it as anything but a game machine or TV Typewriter . In the early part of the 1980s, the dominant microprocessors used in home computers were the 8-bit MOS Technology 6502 (Apple, Commodore, Atari, BBC Micro ) and Zilog Z80 ( TRS-80 , ZX81 , ZX Spectrum , Commodore 128 , Amstrad CPC ). One exception

616-412: A modem ). The VIC has a ROM cartridge port for games and other software as well as for adding memory to the machine. Port expander boxes from Commodore and other vendors allow more than one cartridge to be attached at a time. Cartridge size ranges from 4–16 KB in size, although the latter was uncommon due to its cost. The VIC-20 can be hooked into external electronic circuitry via the joystick port,

770-509: A unit of information , the bit is also known as a shannon , named after Claude E. Shannon . The symbol for the binary digit is either "bit", per the IEC 80000-13 :2008 standard, or the lowercase character "b", per the IEEE 1541-2002 standard. Use of the latter may create confusion with the capital "B" which is the international standard symbol for the byte. The encoding of data by discrete bits

924-427: A 6502 processor and ran DOS from internal ROM. While this gave Commodore systems some advanced capabilities – a utility program could sideload a disk copy routine onto the drive and return control to the user while the drive copied the disk on its own – it also made Commodore drives more expensive and difficult to clone. Many home computers had a cartridge interface which accepted ROM-based software. This

1078-482: A Bell Labs memo on 9 January 1947 in which he contracted "binary information digit" to simply "bit". A bit can be stored by a digital device or other physical system that exists in either of two possible distinct states . These may be the two stable states of a flip-flop , two positions of an electrical switch , two distinct voltage or current levels allowed by a circuit , two distinct levels of light intensity , two directions of magnetization or polarization ,

1232-676: A Commodore engineer who came to Longwood, Florida , to assist in the effort, five of Adams's Adventure International game series were ported to the VIC. They got around the limited memory of VIC-20 by having the 16 KB games reside in a ROM cartridge instead of being loaded into main memory via cassette as they were on the TRS-80 and other machines. The first production run of the five cartridges generated over $ 1,500,000 in sales for Commodore. The VIC-20 went through several variations in its three-and-a-half years of production. First-year models (1980) had

1386-620: A PET-standard Datassette tape drive. The VIC-20 did not originally have a disk drive; the VIC-1540 disk drive was released in 1981. There is one Atari joystick port , compatible with the digital joysticks and paddles used with Atari VCS and Atari 8-bit computers ; a serial CBM-488 bus (a serial version of the PET's IEEE-488 bus) for daisy chaining disk drives and printers; a TTL -level "user port" with both RS-232 and Centronics signals (most frequently used as RS-232, for connecting

1540-554: A PET-style keyboard with a blocky typeface while most VIC-20s made during 1981 had a slightly different keyboard also shared with early C64s. The rainbow logo VIC-20 was introduced in early 1983 and has the newer C64 keyboard with gray function keys and the Revision B motherboard. It has a similar power supply to the C64 PSU , although the amperage is slightly lower. A C64 "black brick" PSU is compatible with Revision B VIC-20s; however,

1694-407: A TV set using the external modulator included with the computer. The VIC chip has three pulse wave generators and a white noise generator with overall volume control and mono output. Each pulse wave generator has a range of three octaves located on the scale about an octave apart, giving a total range of about five octaves. The VIC-20 shipped with 5 KB RAM , but 1.5 KB of this is used for

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1848-429: A bit was represented by the polarity of magnetization of a certain area of a ferromagnetic film, or by a change in polarity from one direction to the other. The same principle was later used in the magnetic bubble memory developed in the 1980s, and is still found in various magnetic strip items such as metro tickets and some credit cards . In modern semiconductor memory , such as dynamic random-access memory ,

2002-486: A built-in keyboard to support its C7420 Home Computer Module. Among third-generation consoles , Nintendo 's Family Computer offered Family BASIC (sold only in Japan), which included a keyboard that could be connected to an external tape recorder to load and store programs. Books of type-in program listings like BASIC Computer Games were available, dedicated for the BASICs of most models of computer, with titles along

2156-604: 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

2310-753: A computer named TOI (The Other Intellect). The TOI computer failed to materialize, mostly because it required an 80-column character display which in turn required the MOS Technology 6564 chip. However, the chip could not be used in the TOI since it required very expensive static RAM to operate fast enough. As the new decade began, the price of computer hardware was dropping and Tramiel saw an emerging market for low-price computers, that could be sold at retail stores to relative novices rather than professionals or people with an electronics or programming background. Radio Shack had been achieving considerable success with

2464-576: A dedicated phone line operated bulletin boards of their own. This capability anticipated the internet by nearly 20 years. Some game consoles offered "programming packs" consisting of a version of BASIC in a ROM cartridge . Atari's BASIC Programming for the Atari 2600 was one of these. For the ColecoVision console, Coleco even announced an expansion module which would convert it into a full-fledged computer system. The Magnavox Odyssey² console had

2618-637: 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. In addition, the small size and limited scope of home computer "operating systems" (really little more than what today would be called a kernel) left little room for bugs to hide. Although modern operating systems include extensive programming libraries to ease development and promote standardization, home computer operating systems provided little support to application programs. Professionally-written software often switched out

2772-470: A first for a stand-alone computer, costing far less than dedicated motion-video processing equipment costing many thousands of dollars. Stereo sound became standard for the first time; the Atari ST gained popularity as an affordable alternative for MIDI equipment for the production of music. Clock rates on the 68000-based systems were approximately 8  MHz with RAM capacities of 256  kB (for

2926-587: A floppy disk drive. It was available for the TRS-80 and some others. A closely-related technology was the ZX Microdrive , developed by Sinclair Research in the UK, for their ZX Spectrum and QL home computers. Eventually, mass production of 5.25" drives resulted in lower prices, and after about 1984, they pushed cassette drives out of the US home computer market. 5.25" floppy disk drives would remain standard until

3080-484: A friendly number and the computer's marketing slogan was 'The Friendly Computer'. I felt it balanced things out a bit since 'Vic' sounded like the name of a truck driver." The graphics capabilities of the VIC chip (6560/6561) are limited but flexible. At startup, the screen shows 176×184 pixels, with a fixed-color border to the edges of the screen. Since a PAL or NTSC screen has a 4:3 width-to-height ratio, each VIC pixel

3234-492: A fully addressable screen, although slightly smaller than normal, by filling the screen with a sequence of different double-height characters, then turning on the pixels selectively inside the RAM-based character definitions. The Super Expander cartridge adds BASIC commands supporting such a graphics mode using a resolution of 160×160 pixels. It is also possible to fill a larger area of the screen with addressable graphics using

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3388-415: A fun and rewarding experience, and an excellent introduction to the world of digital technology. The line between 'business' and 'home' computer market segments vanished completely once IBM PC compatibles became commonly used in the home, since now both categories of computers typically use the same processor architectures, peripherals, operating systems, and applications. Often, the only difference may be

3542-432: A game now and then, learn more about computers, and help educate their children". By 1986, industry experts predicted an "MS-DOS Christmas", and the magazine stated that clones threatened Commodore, Atari, and Apple's domination of the home-computer market. 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

3696-732: A great deal of software support from the traditional Japanese publishers of game software. Microsoft developed the MSX-DOS operating system, a version of their popular MS-DOS adapted to the architecture of these machines, that was also able to run CP/M software directly After the first wave of game consoles and computers landed in American homes, the United States Federal Communications Commission (FCC) began receiving complaints of electromagnetic interference to television reception. By 1979

3850-473: A high performer, the Equity was a reliable and compatible design for half the price of a similarly-configured IBM PC. Epson often promoted sales by bundling one of their printers with it at cost. The Equity I sold well enough to warrant the furtherance of the Equity line with the follow-on Equity II and Equity III. In 1986, UK home computer maker Amstrad began producing their PC1512 PC-compatible for sale in

4004-415: 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 a sharper display, 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. The reason for this

4158-668: A host of other manufacturers. For many of these businesses, the development of the microcomputer made computing and business software affordable where they had not been before. Introduced in August 1981, the IBM Personal Computer would eventually supplant CP/M as the standard platform used in business. This was largely due to the IBM name and the system's 16 bit open architecture , which expanded maximum memory tenfold, and also encouraged production of third-party clones . In

4312-474: A keyboard integrated into the same case as the motherboard , or, more frequently, a mainboard . While the expandable home computers appeared from the very start (the Apple II offered as many as seven expansion slots) as the whole segment was generally aimed downmarket , few offers were priced or positioned high enough to allow for such expandability. Some systems have only one expansion port, often realized in

4466-507: A knowledgeable user who already had applications in mind. If no packaged software was available for a particular application, the home computer user could program one—provided they had invested the requisite hours to learn computer programming , as well as the idiosyncrasies of their system. Since most systems arrived with the BASIC programming language included on the system ROM , it was easy for users to get started creating their own simple applications. Many users found programming to be

4620-570: A luxury gift item, and would have inaugurated the era of home computing, but none were sold. Computers became affordable for the general public in the 1970s due to the mass production of the microprocessor , starting in 1971. Early microcomputers such as the Altair 8800 had front-mounted switches and diagnostic lights (nicknamed " blinkenlights ") to control and indicate internal system status, and were often sold in kit form to hobbyists. These kits would contain an empty printed circuit board which

4774-468: A market for the chip. While newer PETs had the upgraded BASIC 4.0, with disk commands and improved garbage collection , the VIC-20 reverted to the 8 KB BASIC 2.0 used on earlier PETs as part of another of the design team's goals: 20 KB system ROMs. There are no dedicated sound or graphics features. The VIC-20 has a composite output, which provides a sharper, cleaner picture if a dedicated monitor

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4928-462: A more dynamic allocation scheme if the contents are sparse or repetitive enough. This is used by the port of Omega Race . The VIC chip has readable scan-line counters but cannot generate interrupts based on the scan position. The two VIA timer chips can serve this purpose through an elaborate programming technique, allowing graphics to be mixed with text above or below it, two different backgrounds and border colors, or more than 200 characters for

5082-518: A new VIC accessory... We were as surprised as you." The VIC-20 was intended to be more economical than the PET computer. It was equipped with 5  KB of static RAM and used the same MOS 6502 CPU as the PET. The VIC-20's video chip, the MOS Technology VIC , was a general-purpose color video chip designed by Al Charpentier in 1977 and intended for use in inexpensive display terminals and game consoles , but Commodore could not find

5236-686: A palette of 512. MSX was a standard for a home computing architecture that was intended and hoped to become a universal platform for home computing. It was conceived, engineered and marketed by Microsoft Japan with ASCII Corporation . Computers conforming to the MSX standard were produced by most all major Japanese electronics manufacturers, as well as two Korean ones and several others in Europe and South America. Some 5 million units are known to have been sold in Japan alone. They sold in smaller numbers throughout

5390-433: 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 and software 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 would often connect through an RF modulator to

5544-491: A program that allowed businesses to sell computers tax-free to its employees, often accompanied by home training programs. Naturally, these businesses chose to equip their employees with the same systems they themselves were using. 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. Many home computers were superficially similar. Most had

5698-552: A prototype with help from Al Charpentier and Charles Winterble. With the TOI unfinished, when Jack Tramiel was shown the MicroPET prototype, he immediately said he wanted it to be finished and ordered it to be mass-produced following a limited demonstration at the CES. The prototype produced by Yannes had few of the features required for a real computer, so Robert Russell at Commodore headquarters had to coordinate and finish large parts of

5852-506: A reboot to use the system for something else. 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 for disk and file-related commands and was not required to perform other computing functions. One exception was Commodore DOS , which was not loaded into the computer's main memory at all – Commodore disk drives contained

6006-563: A standard of its own, known as Tandy Graphics Adapter or TGA. Later, Tandy produced Tandy 1000 variants in form factors and price-points even more suited to the home computer market, comprised particularly by the Tandy 1000 EX and HX models (later supplanted by the 1000 RL ), which came in cases resembling the original Apple IIs (CPU, keyboard, expansion slots, and power supply in a slimline cabinet) but also included floppy disk drives. The proprietary Deskmate productivity suite came bundled with

6160-404: A time in serial transmission , and by a multiple number of bits in parallel transmission . A bitwise operation optionally processes bits one at a time. Data transfer rates are usually measured in decimal SI multiples of the unit bit per second (bit/s), such as kbit/s. In the earliest non-electronic information processing devices, such as Jacquard's loom or Babbage's Analytical Engine , a bit

6314-485: A turbo NEC V40 CPU (up-rated 8088) which was rather slow for its time, but the video monitor did feature 400-pixel vertical resolution. This unique computer failed for the same reasons as did IBM's PCjr: poor performance and expandability, and a price too high for the home market. Another company that offered low-cost PCs for home use was Leading Edge , with their Model M and Model D computers. These were configured like full-featured business PCs, yet still could compete in

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6468-486: Is in general no meaning to adding, subtracting or otherwise combining the units mathematically, although one may act as a bound on the other. Units of information used in information theory include the shannon (Sh), the natural unit of information (nat) and the hartley (Hart). One shannon is the maximum amount of information needed to specify the state of one bit of storage. These are related by 1 Sh ≈ 0.693 nat ≈ 0.301 Hart. Some authors also define

6622-554: Is more compressed—the same bucket can hold more. For example, it is estimated that the combined technological capacity of the world to store information provides 1,300 exabytes of hardware digits. However, when this storage space is filled and the corresponding content is optimally compressed, this only represents 295 exabytes of information. When optimally compressed, the resulting carrying capacity approaches Shannon information or information entropy . Certain bitwise computer processor instructions (such as bit set ) operate at

6776-434: Is much wider than it is high. The screen normally shows 22 columns and 23 rows of 8-by-8-pixel characters; it is possible to increase these dimensions up to 27 columns, but the characters would soon run out the sides of the monitor at about 25 columns. Just as on the PET, two different 256-character sets are included, the uppercase/graphics character set and the upper/lowercase set, and reverse video versions of both. Normally,

6930-500: Is reorganized if you plug in 8 KB and 16 KB cartridges, leading to a situation where some programs only work if the right amount of memory is present (the most significant divide being between a machine with no or 3 KB extra memory on one hand, and a machine with more extra memory on the other). Most expansion cartridges featured hardware DIP switches , allowing the RAM to be enabled in user-selectable memory blocks. Since

7084-537: Is used. The TRS-80 Color Computer and Atari 400 have only RF video output. An external RF modulator was necessary to use the computer with a TV set. The "20" in the computer's name was widely assumed to refer to the text width of the screen (although in fact, the VIC-20 has 22-column text, not 20) or that it referred to the combined size of the system ROMs (8 KB BASIC+8 KB KERNAL +4 KB character ROM). Bob Yannes claimed that "20" meant nothing in particular and said "We simply picked '20' because it seemed like

7238-662: The Commodore 64 , a more advanced machine with 64 KB of RAM and considerably improved sound and graphics. Initial sales of the C64 were slow but took off in mid-1983. The VIC-20 was widely available for under $ 90 by that time. Commodore discontinued the VIC-20 in January 1985. Perhaps the last new commercially available VIC-20 peripheral was the VIC-Talker, a speech synthesizer . Ahoy! wrote in January 1986, "Believe it or not,

7392-609: The Atari 1040ST (not the 520ST), Amiga , and Tandy 1000 , did house floppy drive(s) internally. At any rate, to expand any computer with additional floppy drives, external units would have to be plugged in. 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

7546-468: The Commodore PET , and the original Apple II in 1977, almost every manufacturer of consumer electronics rushed to introduce a home computer. Large numbers of new machines of all types began to appear during the late 1970s and early 1980s. Mattel , Coleco , Texas Instruments , and Timex , none of which had any prior connection to the computer industry, all had short-lived home computer lines in

7700-465: The Motorola 68008 with its external 8-bit bus). Graphics resolutions approximately doubled to give roughly NTSC -class resolution, and color palettes increased from dozens to hundreds or thousands of colors available. The Amiga was built with a custom chipset with dedicated graphics and sound coprocessors for high-performance video and audio. The Amiga found use as a workstation for desktop video ,

7854-556: The Nintendo Entertainment System , but no longer sold home computers. Toward the end of the 1980s, clones also became popular with non-corporate customers. Inexpensive, highly-compatible clones succeeded where the PCjr had failed. Replacing the hobbyists who had made up the majority of the home computer market were, as Compute! described them, "people who want to take work home from the office now and then, play

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8008-484: The PCjr as a PC/DOS-compatible machine aimed squarely at the home user. It proved a spectacular failure because IBM deliberately limited its capabilities and expansion possibilities in order to avoid cannibalizing sales of the profitable PC. IBM management believed that if they made the PCjr too powerful, too many buyers would prefer it over the bigger, more expensive PC. Poor reviews in the computer press and poor sales doomed

8162-554: 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 low-end models of the 16-bit Amiga and Atari ST families being the dominant players, but by the mid-1990s, even the European market had dwindled. The Dutch government even ran

8316-594: The TRS-80 Color Computer " and "is a much more valuable computer literacy tool than" other products like the TRS-80 Pocket Computer . Compute! concluded "VIC will create its own market, and it will be a big one". While also noting the small screen size and RAM, BYTE stated that the VIC 20 was "unexcelled as low-cost, consumer-oriented computer. Even with some of its limitations...it makes an impressive showing against...the Apple II ,

8470-578: The TRS-80 Model I , a relatively low-cost machine that was widely sold to novices and in 1980 released the Color Computer , which was aimed at the home and educational markets, used ROM cartridges for software, and connected to a TV set. In the meantime, new engineer Robert Yannes at MOS Technology (then a part of Commodore) designed a computer in his home dubbed the MicroPET and finished

8624-410: The yottabit (Ybit). When the information capacity of a storage system or a communication channel is presented in bits or bits per second , this often refers to binary digits, which is a computer hardware capacity to store binary data ( 0 or 1 , up or down, current or not, etc.). Information capacity of a storage system is only an upper bound to the quantity of information stored therein. If

8778-513: The "user port," or the memory expansion cartridge port, which exposes various analog to digital, memory bus, and other internal I/O circuits to the experimenter. PEEK and POKE commands from BASIC can be used to perform data acquisition from temperature sensors, control robotic stepper motors , etc. In 1981, Tomczyk contracted with an outside engineering group to develop a direct-connect modem-on-a-cartridge (the VICModem ), which at US$ 99 became

8932-449: The 1940s, computer builders experimented with a variety of storage methods, such as pressure pulses traveling down a mercury delay line , charges stored on the inside surface of a cathode-ray tube , or opaque spots printed on glass discs by photolithographic techniques. In the 1950s and 1960s, these methods were largely supplanted by magnetic storage devices such as magnetic-core memory , magnetic tapes , drums , and disks , where

9086-455: The 1980s". Television personality Henry Morgan (best known as a panelist on the TV game show I've Got a Secret ) became the commentator in a series of Commodore product ads. The VIC-20 was called VC-20 in Germany and was marketed as though it were an abbreviation of VolksComputer ("people's computer," similar to Volkswagen and Volksempfänger ). Describing it as "an astounding machine for

9240-541: The Atari and Commodore 8-bit machines, coprocessors were added to speed processing of graphics and audio data. For these computers, 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

9394-534: The BASIC interpreter was also used as the user interface , and given tasks such as loading, saving, managing, and running files. One exception was the Jupiter Ace , which had a Forth interpreter instead of BASIC. A built-in programming language was seen as a requirement for any computer of the era, and was the main feature setting home computers apart from video game consoles . Still, home computers competed in

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9548-471: 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. The Atari 400 and 800 were designed with heavy RF shielding to meet the new requirements. Between 1980 and 1982 regulations governing RF emittance from home computers were phased in. Some companies appealed to

9702-643: 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. Kilobit The bit is the most basic unit of information in computing and digital communication . The name is a portmanteau of binary digit . The bit represents a logical state with one of two possible values . These values are most commonly represented as either " 1 " or " 0 " , but other representations such as true / false , yes / no , on / off , or + / − are also widely used. The relation between these values and

9856-529: The IEEE-488 interface on the PET, using smaller cables and connectors that allowed for a more compact case design, and also complying with newly imposed FCC regulations on RFI emissions by home electronics (the PET was certified as Class B office equipment which had less stringent RFI requirements). Some features, like the memory add-in board, were designed by Bill Seiler. Altogether, the VIC 20 development team consisted of five people led by Michael Tomczyk ,

10010-565: The KERNAL. Home computer Home computers were usually sold already manufactured in stylish metal or plastic enclosures. However, some home computers also came as commercial electronic kits , like the Sinclair ZX80 , which were both home and home-built computers since the purchaser could assemble the unit from a kit. Advertisements in the popular press for early home computers were rife with possibilities for their practical use in

10164-526: The Macintosh itself was too expensive for most households. The Amiga in particular had true multitasking capability, and unlike all other low-cost computers of the era, could run multiple applications in their own windows. The second generation of MSX computers (MSX2) achieved the performance of high-performance computers using a high-speed video processor ( Yamaha V9938 ) capable of handling resolutions of 512 ×  424 pixels, and 256 simultaneous colors from

10318-467: The PCjr. Tandy Corporation capitalized on IBM's blunder with its PCjr-compatible Tandy 1000 in November. Like the PCjr, it was pitched as a home, education, and small-business computer, featuring joystick ports, better sound and graphics (same as the PCjr but with enhancements), combined with near-PC/DOS compatibility (unlike Tandy's earlier Tandy 2000 ). The improved Tandy 1000 video hardware became

10472-519: The ROM-based OS anyway to free the address space it occupied and maximize RAM capacity. This gave the program full control of the hardware and allowed the programmer to optimize performance for a specific task. Games would often turn off unused I/O ports, as well as the interrupts that served them. As multitasking was never common on home computers, this practice went largely unnoticed by users. Most software even lacked an exit command, requiring

10626-544: The Radio Shack TRS-80 , and the Atari 800 ". The magazine praised the price ("Looking at a picture...might cause you to think $ 600 would be a fair price...But it does not cost $ 600 —the VIC 20 retails for $ 299.95 "), keyboard ("the equal of any personal-computer keyboard in both appearance and performance. This is a remarkable achievement, almost unbelievable considering the price of the entire unit"), graphics, documentation, and ease of software development with

10780-549: The Tandy 1000s. Deskmate was suited to use by computer novices with its point-and-click (though not graphical) user interface. From the launch of the Tandy 1000 series, their manufacture were price-competitive because of Tandy's use of high-density ASIC chip technology, which allowed their engineers to integrate many hardware features into the motherboard (obviating the need for circuit cards in expansion slots as with other brands of PC). Tandy never transferred its manufacturing operation to Asia; all Tandy desktop computers were built in

10934-664: The UK. Later they would market the machine in the US as the PC6400. In June 1987, an improved model was produced as the PC1640. These machines had fast 8086 CPUs, enhanced CGA graphics, and were feature-laden for their modest prices. They had joystick adapters built into their keyboards and shipped with a licensed version of the Digital Research 's GEM , a GUI for the MS-DOS operating system. They became marginal successes in

11088-654: The USA (this was not true of the laptop and pocket computers, nor peripherals). In 1985, the Epson corporation, a popular and respected producer of inexpensive dot-matrix printers and business computers (the QX-10 and QX-16 ), introduced its low-cost Epson Equity PC. Its designers took minor shortcuts, such as few expansion slots and a lack of a socket for an 8087 math chip, but Epson did bundle some utility programs that offered decent turnkey functionality for novice users. While not

11242-428: The VIC's PSU is not recommended on a C64 if any external devices, such as cartridges or user port accessories, are installed, as it will overdraw the available power. Older Revision A VIC-20s cannot use a C64 PSU or vice versa as their power requirement is too high. The VIC-20 was a bestseller, becoming the first computer to sell over a million. In total, 2.5 million computers were sold. In summer 1982, Commodore unveiled

11396-400: The VIC-20 operates in a high-resolution mode whereby each character is 8×8 pixels in size and uses one color. A lower-resolution multicolor mode can also be used with 4×8 characters and three colors each, but it is not used as often due to its extreme blockiness. The VIC chip does not support a true bitmap mode, but programmers can define their own custom character sets. It is possible to get

11550-482: The VIC-20 was designed to use SRAM rather than DRAM , the system board has no provisions for DRAM refresh. RAM expansion cartridges ultimately allowed adding up to 24 KB to the BASIC user memory; together with the 3.5 KB built-in user memory, this gave a maximum of 27.5 KB for BASIC programs and variables. Memory not visible to BASIC could still be used by machine code programs. The VIC-20 has card edge connectors for program/expansion cartridges and

11704-500: The VIC-20. An estimated 300 commercial titles were available on cartridge and another 500+ were available on tape. A handful of disk applications were released. The VIC's low cost led to it being used by the Fort Pierce, Florida , Utilities Authority to measure the input and output of two of their generators and display the results on monitors throughout the plant. The utility was able to purchase multiple VIC and C64 systems for

11858-431: The ability to run industry-standard MS-DOS software on affordable, user-friendly PCs was anticipated as a source of new sales. Furthermore, many in the industry felt that MS-DOS would eventually (inevitably, it seemed) come to dominate the computer business entirely, and some manufacturers felt the need to offer individual customers PC-style products suitable for the home market. In early 1984, market colossus IBM produced

12012-409: The ambiguity of relying on the underlying hardware design, the unit octet was defined to explicitly denote a sequence of eight bits. Computers usually manipulate bits in groups of a fixed size, conventionally named " words ". Like the byte, the number of bits in a word also varies with the hardware design, and is typically between 8 and 80 bits, or even more in some specialized computers. In

12166-481: 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—one that had the advantage of incorporating its own documentation. These books also served a role in familiarizing new computer owners with the concepts of programming; some titles added suggested modifications to

12320-424: The average. This principle is the basis of data compression technology. Using an analogy, the hardware binary digits refer to the amount of storage space available (like the number of buckets available to store things), and the information content the filling, which comes in different levels of granularity (fine or coarse, that is, compressed or uncompressed information). When the granularity is finer—when information

12474-477: The base Amiga 1000 ) up to 1024 kB ( 1  MB , 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 with windowing technology. These were inspired by the Macintosh , but at a list price of US$ 2,495 (equivalent to $ 7,100 in 2023),

12628-500: The buyer would fill with the integrated circuits , other individual electronic components, wires and connectors, and then hand- solder all the connections. 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

12782-435: The company's encouragement of "cottage industry software developers" to Texas Instruments discouraging third-party software . Because of its small memory and low-resolution display compared to some other computers of the time, the VIC-20 was primarily used for educational software and games. However, productivity applications such as home finance programs, spreadsheets, and communication terminal programs were also made for

12936-507: The cost of one IBM PC compatible . While the PET was sold through authorized dealers the VIC-20 primarily sold at retail, especially discount and toy stores, where it could compete directly with game consoles. It was the first computer to be sold in K-Mart . Commodore took out advertisements featuring actor William Shatner (of Star Trek fame) as its spokesman, asking: "Why buy just a video game?" and describing it as "The Wonder Computer of

13090-477: The default PC floppy was double-sided, with about twice the storage capacity of floppy disks used by 8-bit home computers. PC drives tended to cost less because they were most often built-in, requiring no external case, controller, or power supply. The faster clock rates and wider buses available to later Intel CPUs compensated somewhat for the custom graphics and sound chips of the Commodores and Ataris. In time,

13244-480: The design under the codename Vixen . The parts contributed by Russell included a port of the operating system (kernel and BASIC interpreter ) taken from John Feagan's design for the Commodore PET , a character set with the characteristic PETSCII , an Atari CX40 joystick -compatible interface, and a ROM cartridge port. The serial IEEE-488 -derivative CBM-488 interface was designed by Glen Stark. It served several purposes, including costing substantially less than

13398-506: The design. The VIC-20 was marketed in Japan as VIC-1001 before VIC-20 was introduced to the US. When they returned to California from that meeting, Tomczyk wrote a 30-page memo detailing recommendations for the new computer and presented it to Tramiel. Recommendations included programmable function keys (inspired by competing Japanese computers), full-size typewriter-style keys, and built-in RS-232 . Tomczyk insisted on " user-friendliness " as

13552-478: The early 1980s. Some home computers were more successful. The BBC Micro , Sinclair ZX Spectrum , Atari 8-bit computers , and Commodore 64 sold many units over several years and attracted third-party software development. Almost universally, home computers had a BASIC interpreter combined with a line editor in permanent read-only memory , which one could use to type in BASIC programs and execute them immediately, or save them to tape or disk. In direct mode ,

13706-415: The early 21st century, retail personal or server computers have a word size of 32 or 64 bits. The International System of Units defines a series of decimal prefixes for multiples of standardized units which are commonly also used with the bit and the byte. The prefixes kilo (10 ) through yotta (10 ) increment by multiples of one thousand, and the corresponding units are the kilobit (kbit) through

13860-493: 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, almost all software sold for 8-bit home computers remained on 5.25" disks. 3.5" drives were used for data storage, with the exception of the Japanese MSX standard, on which 5.25" floppies were never popular. Standardization of disk formats was not common; sometimes, even different models from

14014-416: The family TV set, which served as both video display and sound system. The rise of the home computer also led to a fundamental shift during the early 1980s in where and how computers were purchased. Traditionally, microcomputers were obtained by mail order or were purchased in person at general electronics retailers like RadioShack . Silicon Valley , in the vanguard of the personal computer revolution,

14168-465: The few business users. 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

14322-449: 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." As the Apple II gained momentum with the advent of VisiCalc in 1979, Jack Tramiel wanted a product that would compete in the same segment, to be presented at the January 1980 CES . For this reason Chuck Peddle and Bill Seiler started to design

14476-575: The first modem priced under US$ 100. The VICModem was also the first modem to sell over 1 million units. VICModem was packaged with US$ 197.50 worth of free telecomputing services from The Source , CompuServe , and Dow Jones . Tomczyk also created a SIG called the Commodore Information Network to enable users to exchange information and take some of the pressure off of Customer Support inquiries, which were straining Commodore's lean organization. In 1982, this network accounted for

14630-405: The first modem to sell 1 million units. According to one of the development team, Neil Harris, "[W]e couldn't get any cooperation from the rest of the company who thought we were jokers because we were working late, about an hour after everyone else had left the building. We'd swipe whatever equipment we needed to get our jobs done. There was no other way to get the work done! [...] they'd discover it

14784-477: The form of cumbersome "sidecar" systems, such as on the TI-99/4 , or required finicky and unwieldy ribbon cables to connect the expansion modules. Sometimes they were equipped with a cheap 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

14938-606: The game console showed a blank screen or continued playing the same repetitive game. Another capability home computers had that game consoles of the time lacked was the ability to access remote services over telephone lines by adding a serial port interface, a modem , and communication software . Though it could be costly, it permitted the computer user to access services like Compuserve , and private or corporate bulletin board systems and viewdata services to post or read messages, or to download or upload software. Some enthusiasts with computers equipped with large storage capacity and

15092-414: The growing popularity of home PCs spurred many software publishers to offer gaming and children's software titles. Many decision-makers in the computer industry believed there could be a viable market for office workers who used PC/DOS computers at their jobs and would appreciate an ability to bring diskettes of data home on weeknights and weekends to continue work after-hours on their "home" computers. So,

15246-451: The home market on price because Leading Edge had access to low-cost hardware from their Asian manufacturing partners Mitsubishi with the Model M and Daewoo with the Model D. The LEWP was bundled with the Model D. It was favorably reviewed by the computer press and sold very well. By the mid '80s, the market for inexpensive PCs for use in the home market was expanding at such a rate that

15400-483: The home market. In 1987, longtime small computer maker Zenith introduced a low-cost PC they called the EaZy PC . This was positioned as an "appliance" computer much like the original Apple Macintosh: turnkey startup, built-in monochrome video monitor, and lacking expansion slots, requiring proprietary add-ons available only from Zenith, but instead with the traditional MS-DOS Command-line interface . The EaZy PC used

15554-489: The home". In 1990, the company reportedly refused to support joysticks on its low-cost Macintosh LC and IIsi computers to prevent customers from considering them as "game machines". Although the Apple II and Atari computers are functionally similar, Atari's home-oriented marketing resulted in a game-heavy library with much less business software. By the late 1980s, many mass merchants sold video game consoles like

15708-466: The home, from cataloging recipes to personal finance to home automation , 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, assuming

15862-462: The image of, as Compute! wrote, "a low-powered, low-end machine primarily suited for playing games". Apple consistently avoided stating that it was a home-computer company, and described the IIc as "a serious computer for the serious home user", despite competing against IBM's PCjr home computer. John Sculley denied that his company sold home computers; rather, he said, Apple sold "computers for use in

16016-609: 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 were either built-in or available on expansion cards . Although the Apple II had internal expansion slots, most other home computer models' expansion arrangements were through externally-accessible 'expansion ports' that also served as

16170-650: The largest traffic on CompuServe. Commodore's VIC-1010 Expansion allows the user to connect multiple devices to the VIC-20's cartridge port. It has its own power supply and six slots that can be used to connect memory extensions, game cartridges or other peripherals. The VIC-20's BASIC is compatible with the PET's, and the Datasette format is the same. Before the computer's release, a Commodore executive promised it would have "enough additional documentation to enable an experienced programmer/hobbyist to get inside and let his imagination work". Compute! favorably contrasted

16324-406: The late 1970s, the 6502-based Apple II had carved out a niche for itself in business, thanks to the industry's first killer app , VisiCalc , released in 1979. However, the Apple II would quickly be displaced for office use by IBM PC compatibles running Lotus 1-2-3 . Apple Computer 's 1980 Apple III was underwhelming, and although the 1984 release of the Macintosh introduced the modern GUI to

16478-409: The level of manipulating bits rather than manipulating data interpreted as an aggregate of bits. In the 1980s, when bitmapped computer displays became popular, some computers provided specialized bit block transfer instructions to set or copy the bits that corresponded to a given rectangular area on the screen. In most computers and programming languages, when a bit within a group of bits, such as

16632-402: The lines of 64 Amazing BASIC Games for the Commodore 64 . 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

16786-520: The machine. The VIC had a sizable library of public domain and freeware software. This software was distributed via online services such as CompuServe, BBSs , as well as offline by mail order and by user groups. Several computer magazines sold on newsstands, such as Compute! , Family Computing , RUN , Ahoy! , and the CBM-produced Commodore Power/Play , offered programming tips and type-in programs for

16940-512: The market, it was not common until IBM-compatible computers adopted it. Throughout the 1980s, businesses large and small adopted the PC platform, leading, by the end of the decade, to sub-US$ 1000 IBM PC XT -class white box machines, usually built in Asia and sold by US companies like PCs Limited . In 1980, Wayne Green , the publisher of Kilobaud Microcomputing , recommended that companies avoid

17094-539: The memory count to five chips: 2× 2048-byte chips + 3× 2114 (the 1024 × 4 bits) chips. In April 1980, at a meeting of general managers outside London, Jack Tramiel declared he wanted a low-cost color computer. When most of the GMs argued against it, preferring Peddle's more sophisticated design, he said: "The Japanese are coming, so we must become the Japanese!" (in reference to the threats of low-cost systems from Japan). This

17248-585: The more ambitious computers. As the amount of memory on the VIC-20's system board was very small even for 1981 standards, the design team could get away with using more expensive SRAM due to its lower power consumption, heat output, and less supporting circuitry. The original Revision A system board found in all silver-label VIC-20s used 2114 SRAMs and due to their tiny size (only 512 bytes per chip), ten of them were required to reach 5 KB of system RAM. The Revision B system board, found in rainbow logo VIC-20s (see below) switched to larger 2048-byte SRAMs which reduced

17402-664: The new machine and its MS-DOS operating system. Even basic PCs cost thousands of dollars and were far out of reach for typical home computer users. However, in the following years, technological advances and improved manufacturing capabilities (mainly greater use of robotics and relocation of production plants to lower-wage locations in Asia) permitted several computer companies to offer lower-cost, PC-style machines that would become competitive with many 8-bit home-market pioneers like Radio Shack, Commodore, Atari, Texas Instruments, and Sinclair. PCs could never become as affordable as these because

17556-408: The orientation of reversible double stranded DNA , etc. Bits can be implemented in several forms. In most modern computing devices, a bit is usually represented by an electrical voltage or current pulse, or by the electrical state of a flip-flop circuit. For devices using positive logic , a digit value of 1 (or a logical value of true) is represented by a more positive voltage relative to

17710-443: The physical states of the underlying storage or device is a matter of convention, and different assignments may be used even within the same device or program . It may be physically implemented with a two-state device. A contiguous group of binary digits is commonly called a bit string , a bit vector, or a single-dimensional (or multi-dimensional) bit array . A group of eight bits is called one  byte , but historically

17864-546: The price difference between old 8-bit technology and new PCs. Despite their higher absolute prices, PCs were perceived by many to be better values for their utility as superior productivity tools and their access to industry-standard software. Another advantage was the 8088/8086's wide, 20-bit address bus. The PC could access more than 64 kilobytes of memory relatively inexpensively (8-bit CPUs, which generally had multiplexed 16-bit address buses, required complicated, tricky memory management techniques like bank-switching ). Similarly,

18018-415: The price", Compute! in 1981 expected the VIC-20 would be popular in classrooms and homes with small children, with "excellent graphic and sound capabilities". While predicting the 22-column screen was "too small to support any but the most rudimentary business applications" the magazine observed that "at a price of $ 299 , that is hardly the point", stating that "the VIC will provide very stiff competition to

18172-422: The prime directive for the new computer, to engineer Terakura, and proposed a retail price of US$ 299.95 . He recruited a marketing team and a small group of computer enthusiasts and worked closely with colleagues in the UK and Japan to create colorful packaging, user manuals, and the first wave of games and home applications. Scott Adams was contracted to provide a series of text adventure games. With help from

18326-585: The product manager who recruited the group and dubbed them the VIC Commandos. Commodore founder Jack Tramiel initially gave Tomczyk the title VIC Czar and later appointed him product manager. Tomczyk insisted on several features including full-size typewriter keys, programmable function keys, and a built-in RS-232 interface. Michael later contracted and co-designed a $ 100 modem, the VICModem, which became

18480-474: The program listings for the user to carry out. Applying a patch to modify software to be compatible with one's system, or writing a utility program to fit one's needs, was a skill every advanced computer owner was expected to have. During the peak years of the home computer market, scores of models were produced, usually as individual design projects with little or no thought given to compatibility between different manufacturers, or even within product lines of

18634-419: The pseudo-high-resolution mode. The VIC chip can process a light pen signal via the joystick port, but few appeared on the market. The VIC chip outputs Luma +Sync and Chroma video signals, which are combined to create the VIC-20's composite video output. Commodore did not include an RF modulator inside the computer's case because of FCC regulations. It can either be attached to a dedicated monitor or

18788-501: The recording back through the modem to "load". Most cassette implementations were notoriously slow and unreliable, but 8" drives were too bulky for home use, and early 5.25" form-factor drives were priced for business use, out of reach of most home buyers. An innovative alternative was the Exatron Stringy Floppy , a continuous-loop tape drive which was much faster than a data cassette drive and could perform much like

18942-517: The representation of 0 . Different logic families require different voltages, and variations are allowed to account for component aging and noise immunity. For example, in transistor–transistor logic (TTL) and compatible circuits, digit values 0 and 1 at the output of a device are represented by no higher than 0.4 V and no lower than 2.6 V, respectively; while TTL inputs are specified to recognize 0.8 V or below as 0 and 2.2 V or above as 1 . Bits are transmitted one at

19096-490: The sales outlet through which they are purchased. Another change from the home computer era is that the once-common endeavor of writing one's own software programs has almost vanished from home computer use. As early as 1965, some experimental projects, such as Jim Sutherland's ECHO IV , explored the possible utility of a computer in the home. In 1969, the Honeywell Kitchen Computer was marketed as

19250-400: The same as the PET monitor but added a mini- assembler instead of requiring the user to enter hexadecimal opcodes . The VIC-20's RAM is expandable through the cartridge port via a RAM cartridge. RAM cartridges were available from Commodore in several sizes: 3 KB (with or without an included "Super Expander" BASIC extension ROM), 8 KB , and 16 KB . The internal memory map

19404-518: The same manufacturer used different disk formats. Almost universally, the floppy disk drives available for 8-bit home computers were housed in external cases, with their own controller boards and power supplies contained within. Only the later, advanced 8-bit home computers housed their drives within the main unit; these included the TRS-80 Model III , TRS-80 Model 4 , Apple IIc , MSX2 , and Commodore 128D . The later 16-bit machines, such as

19558-445: The same manufacturer. Except for the Japanese MSX standard, the concept of a computer platform was still forming, with most companies considering rudimentary BASIC language and disk format compatibility sufficient to claim a model as "compatible". Things were different in the business world, where cost-conscious small business owners had been using CP/M running on Z80 -based computers from Osborne , Kaypro , Morrow Designs , and

19712-473: The same market as the consoles. A home computer was often seen as simply a higher-end purchase than a console, adding abilities and productivity potential 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 emphasizing the computer's greater ability by showing it running user-created programs, education software, word processing, spreadsheet, and other applications, while

19866-418: The same price-reducing measures were available to all computer makers. Furthermore, software and peripherals for PC-style computers tended to cost more than those for 8-bit computers because of the anchoring effect caused by the pricey IBM PC. As well, PCs were inherently more expensive since they could not use the home TV set as a video display. Nonetheless, the overall reduction in manufacturing costs narrowed

20020-444: 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

20174-424: The size of the byte is not strictly defined. Frequently, half, full, double and quadruple words consist of a number of bytes which is a low power of two. A string of four bits is usually a nibble . In information theory , one bit is the information entropy of a random binary variable that is 0 or 1 with equal probability, or the information that is gained when the value of such a variable becomes known. As

20328-406: The term "home computer" in their advertising, as it "I feel is self-limiting for sales...I prefer the term "microcomputers" since it doesn't limit the uses of the equipment in the imagination of the prospective customers". With the exception of Tandy, most computer companies – even those with a majority of sales to home users – agreed, avoiding the term "home computer" because of its association with

20482-577: The thickness of alternating black and white lines. The bit is not defined in the International System of Units (SI). However, the International Electrotechnical Commission issued standard IEC 60027 , which specifies that the symbol for binary digit should be 'bit', and this should be used in all multiples, such as 'kbit', for kilobit. However, the lower-case letter 'b' is widely used as well and

20636-599: The time 1801 series CPU , offering a full PDP-11 compatibility and a fully functional Q-Bus slot, though at the cost of very anemic RAM and graphics. The Motorola 6809 was used by the Radio Shack TRS-80 Color Computer , the Fujitsu FM-7 , and Dragon 32/64 . Processor clock rates were typically 1–2 MHz for 6502 and 6809-based CPUs and 2–4 MHz for Z80-based systems (yielding roughly equal performance), but this aspect

20790-501: The transition from 5.25" to 3.5" format at the time (though 5.25" drives remained common on PCs until the late 1990s, due to existence of the large software and data archives on five-inch floppies). 5.25" drives were made available for the ST, Amiga, and Macintosh, otherwise 3.5" based systems with no other use for a 5.25" format. Hard drives were never popular on home computers, remaining an expensive, niche product mainly for BBS sysops and

20944-836: The two leaders in the US, Commodore and Atari, themselves felt compelled to enter the market with their own lines. They were only marginally successful compared to other companies that made only PCs. Still, later prices of white box PC clone computers by various manufacturers became competitive with the higher-end home computers (see below). Throughout the 1980s, costs and prices continued to be driven down by: advanced circuit design and manufacturing, multi-function expansion cards, shareware applications such as PC-Talk , PC-Write , and PC-File , greater hardware reliability, and more user-friendly software that demanded less customer support services. The increasing availability of faster processor and memory chips, inexpensive EGA and VGA video cards, sound cards , and joystick adapters also bolstered

21098-556: The two possible values of one bit of storage are not equally likely, that bit of storage contains less than one bit of information. If the value is completely predictable, then the reading of that value provides no information at all (zero entropic bits, because no resolution of uncertainty occurs and therefore no information is available). If a computer file that uses n  bits of storage contains only m  <  n  bits of information, then that information can in principle be encoded in about m  bits, at least on

21252-444: The two values of a bit may be represented by two levels of electric charge stored in a capacitor . In certain types of programmable logic arrays and read-only memory , a bit may be represented by the presence or absence of a conducting path at a certain point of a circuit. In optical discs , a bit is encoded as the presence or absence of a microscopic pit on a reflective surface. In one-dimensional bar codes , bits are encoded as

21406-509: The viability of PC/DOS computers as alternatives to specially-made computers and game consoles for the home. 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 (in the UK, the Sinclair QL was built around

21560-473: The video display and dynamic aspects of the ROM -resident Commodore BASIC and KERNAL (a low-level operating system). Only 3,583 bytes of BASIC program memory for code and variables are actually available on an unexpanded machine. Unlike the PET, the VIC-20 does not include a machine language monitor , but Commodore offered them on disk, tape, or cartridge, with several different executables to load into various memory locations. The monitor programs were

21714-548: The world. Due to the "price wars" being waged in the USA home computer market during the 1983-85 period, MSX computers were never marketed to any great extent in the USA. Eventually more advanced mainstream home computers and game consoles obsoleted the MSX machines. The MSX computers were built around the Zilog Z80 8-bit processor, assisted with dedicated video graphics and audio coprocessors supplied by Intel , Texas Instruments , and General Instrument . MSX computers received

21868-573: Was also used for expansion or upgrades such as fast loaders . Application software on cartridge did exist, which loaded instantly and eliminated the need for disk swapping on single-drive setups, but the vast majority of cartridges were games. From the introduction of the IBM Personal Computer (ubiquitously known as the PC) in 1981, the market for computers meant for the corporate, business, and government sectors came to be dominated by

22022-451: Was also used in Morse code (1844) and early digital communications machines such as teletypes and stock ticker machines (1870). Ralph Hartley suggested the use of a logarithmic measure of information in 1928. Claude E. Shannon first used the word "bit" in his seminal 1948 paper " A Mathematical Theory of Communication ". He attributed its origin to John W. Tukey , who had written

22176-540: Was in keeping with Tramiel's philosophy which was to make "computers for the masses, not the classes". The concept was supported at the meeting by Tomczyk, newly hired marketing strategist and assistant to the president; Tony Tokai, General Manager of Commodore Japan, and Kit Spencer, the UK's top marketing executive. Peddle disagreed with the decision and left the company with other engineers, so an engineering team in Commodore Japan led by Yash Terakura helped finish

22330-412: Was missing and they would just order more stuff from the warehouse, so everybody had what they needed to do their work." At the time, Commodore had a glut of 1 Kbit ×4 SRAM chips, so Tramiel decided these should be used in the new computer. The result was arguably closer to the PET or TOI computers than to Yannes' prototype, albeit with a 22-column VIC chip instead of the custom chips designed for

22484-424: 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. For low-price computers, the cost of RAM memory chips contributed greatly to the final product price to the consumer, and fast CPUs demanded expensive, fast memory. As a result, designers kept clock rates only adequate. In some cases, like

22638-460: Was often stored as the position of a mechanical lever or gear, or the presence or absence of a hole at a specific point of a paper card or tape . The first electrical devices for discrete logic (such as elevator and traffic light control circuits , telephone switches , and Konrad Zuse's computer) represented bits as the states of electrical relays which could be either "open" or "closed". When relays were replaced by vacuum tubes , starting in

22792-507: Was recommended by the IEEE 1541 Standard (2002) . In contrast, the upper case letter 'B' is the standard and customary symbol for byte. Multiple bits may be expressed and represented in several ways. For convenience of representing commonly reoccurring groups of bits in information technology, several units of information have traditionally been used. The most common is the unit byte , coined by Werner Buchholz in June 1956, which historically

22946-417: Was that while those TV-monitors had difficulty displaying the clear and readable 80-column text that became the industry standard at the time, the only consumers who really needed that were the power users utilizing the machine for business purposes, while the average casual consumer would use the system for games only and was content with the lower resolution, for which a TV worked fine. An important exception

23100-474: Was the Radio Shack TRS-80 , the first mass-marketed computer for home use, which included its own 64-column display monitor and full-travel keyboard as standard features. This " peripherals sold separately" approach is another defining characteristic of the home computer era. A first-time computer buyer who brought a base C-64 system home and hooked it up to their TV would find they needed to buy

23254-501: Was the TI-99/4 , announced in 1979 with a 16-bit TMS9900 CPU. The TI was originally to use the 8-bit 9985 processor designed especially for it, but this project was cancelled. However, the glue logic needed to retrofit the 16-bit CPU to an 8-bit 9985 system negated the advantages of the more powerful CPU. Another exception was the Soviet Elektronika BK series of 1984, which used the fully-16-bit and powerful for

23408-424: Was the first place to see the appearance of new retail stores dedicated to selling only computer hardware, computer software, or both, and also the first place where such stores began to specialize in particular platforms. By 1982, an estimated 621,000 home computers were in American households, at an average sales price of US$ 530 (equivalent to $ 1,673 in 2023). After the success of the Radio Shack TRS-80 ,

23562-541: Was used in the punched cards invented by Basile Bouchon and Jean-Baptiste Falcon (1732), developed by Joseph Marie Jacquard (1804), and later adopted by Semyon Korsakov , Charles Babbage , Herman Hollerith , and early computer manufacturers like IBM . A variant of that idea was the perforated paper tape . In all those systems, the medium (card or tape) conceptually carried an array of hole positions; each position could be either punched through or not, thus carrying one bit of information. The encoding of text by bits

23716-405: Was used to represent the group of bits used to encode a single character of text (until UTF-8 multibyte encoding took over) in a computer and for this reason it was used as the basic addressable element in many computer architectures . The trend in hardware design converged on the most common implementation of using eight bits per byte, as it is widely used today. However, because of

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