IBM PCJr with original "chiclet" keyboard, PCjr Color Display, and 64KB memory expansion card
|Manufacturer||Teledyne, Lewisburg, Tennessee|
|Release date||March 1984|
|Introductory price||$1,269 with 128KB memory and without monitor|
|Discontinued||April 2, 1987|
|Operating system||IBM PC DOS 2.10|
|CPU||Intel 8088 @ 4.77 MHz|
|Graphics||Video Gate Array|
|Sound||Texas Instruments SN76489|
The IBM PCjr (read "PC junior") was IBM's first attempt to enter the home computer market. The PCjr, IBM model number 4860, retains the IBM PC's 8088 CPU and BIOS interface for compatibility, but various design and implementation decisions led the PCjr to be a commercial failure.
- 1 Description
- 2 History
- 3 Legacy
- 4 Technical specifications
- 5 See also
- 6 References
- 7 External links
Announced November 1, 1983, and first shipped in late January 1984, the PCjr—nicknamed "Peanut" before its debut—came in two models: the 4860-004, with 64 KB of memory, priced at US$669 (equivalent to $1,584 in present-day terms); and the 4860-067, with 128 KB of memory and a 360 KB 5.25-inch floppy disk drive, priced at US$1269 (equivalent to $3,005 in present-day terms). It was manufactured for IBM in Lewisburg, Tennessee by Teledyne. The PCjr promised a high degree of compatibility with the IBM PC, which was already a popular business computer, in addition to offering built-in color graphics and 3 voice sound that were better than the standard PC speaker sound and color graphics of the standard IBM PC and compatibles of the day.
The graphics are produced via a graphics chip known as the Video Gate Array (VGA), an upward-compatible extension of CGA which added three new graphics modes to CGA's seven. The PCjr's sound is provided by a Texas Instruments SN76489 which can produce three square waves of varying amplitude and frequency along with a noise channel powered by a shift register. The PCjr was also the first PC compatible machine that supported page flipping for graphics operation. Since the PCjr uses system RAM to store video content and the location of this storage area can be changed, the PCjr can perform flicker-free animation and other effects that were either difficult or impossible to produce on contemporary PC clones.
The PCjr's 4.77 MHz Intel 8088 CPU is faster than that of other computers that were aimed at the home market at the time, though the PCjr does not run at the full rated 4.77 MHz because every 4th clock cycle of the 8088 CPU is designated to refresh the PCjr's dynamic RAM as it has no dedicated memory controller; the computer's effective clockspeed is therefore 3.58 MHz. The detached wireless infrared keyboard promised a degree of convenience none of its competitors had, eliciting visions of word-processing wirelessly from one's couch with the computer connected to a TV set as a display.
Differences from the IBM PC
With a built-in RF modulator, the PCjr could send video and audio to a TV; it also had an audio output jack to connect to a stereo or amplifier. Cartridge BASIC enhanced the standard IBM BASIC with commands to support the new video and audio functionality. Two joystick ports were also evidence of IBM's goal for marketing the PCjr as a home-friendly machine. Other than the Tandy 1000 and Amstrad IBM PC compatible lines a few years later, the dual built-in joystick ports introduced by the PCjr never became standard on IBM PC compatibles, and have not been seen since. Also, in addition to the joystick ports having a different connector from PC game ports, they required joysticks that had a different electrical resistance range in their X/Y axis controllers, necessitating the use of PCjr-compatible joysticks.
The PCjr's video used 16K of RAM as shared graphics memory, which prevented using additional memory with the built-in 128K in a flat model. Two solutions existed: Use the additional memory as a ramdisk, or not use the built-in 128K.
Further reinforcing the "home-friendly" goal, the PCjr also introduced two ROM cartridge slots on the front of the unit, meant to load software quickly and easily. The cartridge(s) would be plugged in from the front, prompting the computer to automatically reboot and run the software. This was more user-friendly than other home computer systems, which had to be powered off when a cartridge was removed or inserted and came with dire warnings about damage to the computer's main board if this requirement was ignored. Loading and saving data from cartridge software was possible via the floppy drive. The cartridge BASIC for the PCjr, in particular, gave programmers the advantage of a real programming language always ready without taking up system memory, as it was firmware, with its own address space. Being stored in ROM, the BASIC would load very quickly, not needing access to the floppy disk or other storage.
Cartridges could also replace the system BIOS and other firmware. A number of patches from various vendors were included on a single "combo-cartridge", licensed and sold by PC Enterprises, to support add-on hardware, bypass certain limitations of design, and keep up with changing OS requirements.
Expansions (such as additional parallel ports, serial ports, memory, etc.) to the PCjr were provided via add-on "sidecars" that attached to the side of the PCjr. Multiple expansions were stacked together, increasing the width of the machine.
Differences from other personal computers
The PCjr was shipped with a wireless chiclet keyboard called the "Freeboard", powered by four AA batteries to provide infrared line-of-sight wireless communication. The keycaps were blank; labels appeared between keys to permit overlays. Certain room lights caused interference with the infrared keyboard sensor. The keyboard could also operate with an optional modular telephone-style cable if so desired, eliminating battery usage. The PCjr also had a lightpen port; it was later used in combination with the serial port to supply voltage to a Mouse Systems optical mouse of the same design as Sun workstations.
IBM in the early 1980s was the world's largest computer company. With 70% of the mainframe market, it had larger revenues than Apple, Compaq, DEC, HP, and TI combined. When it introduced its first personal computer in August 1981, IBM did so to defend itself against Apple and other companies' newly popular microcomputers. Within two years the IBM PC created a large new ecosystem of PC clones and software. Surprising even company executives, it became a market leader with 26% of all microcomputers sold in 1983, in second place to the much less-expensive Commodore 64 and three times the Apple II's share.
For a year before the PCjr's announcement the computer industry discussed rumors of a new product, code named "Peanut", that would repeat the PC's success. The rumors described Peanut as a home computer with 64K of memory that would be compatible with the large IBM PC software library, would benefit from IBM's service network, and, at $600 to $1,000, would be less expensive than the Apple IIe. Customers waited for the rumored IBM product, crippling competitors' sales, and other companies' product plans and stocks reacted to the officially nonexistent computer in what the press called "Peanut Panic" or "The Great Peanut Roast". While IBM repeatedly denied the rumors it estimated that 50 to 70% of PCs sold in retail stores went to the home, a market which CEO John Opel described as "inevitable as the sunrise tomorrow" for the company; the success "of the Peanut is as good as established", one magazine predicted.
|“||D-Day for the Home Computer||”|
—Time, 7 November 1983
IBM launched the PCjr at its New York City headquarters in November 1983 with an enormous amount of advance publicity, including live news-broadcast coverage of the product announcement. Compute! wrote "Never before in the history of personal computing (admittedly a brief history) has a product been so eagerly awaited by so many". PC expert Peter Norton wrote that the new computer "has all, or nearly all, the capacity and flexibility that most of us who are already using PC's need ... All in all, the PCjr looks like a remarkable machine for its capabilities and an astounding one for its price", and predicted that "the PCjr will make an even bigger splash" than the PC. Time called its debut "D-Day for the Home Computer"; experts predicted sales of one million or more in 1984, and expected the PCjr to change the home-computer market in a similar way to how the IBM PC had single-handedly changed the business-microcomputer market. They predicted that the PCjr would extend IBM's dominance, with customers able to use the company's computers in the home and in the office.
Observers believed that, as PC Magazine reported, IBM did not "face substantial competition on the home front" from computers that many considered "mere gadgets or expensive toys". Even competitors hoped that a home computer with, as Popular Science wrote,
the three initials on its nameplate, letters that, in the minds of many, represent quality, reliability, and an assurance that the company will be around for as long as the computer is
would stabilize and bring credibility to the chaotic market, which had seen "cutthroat" price wars between Commodore, Atari, and others.  TI left the market the same week as IBM's announcement, after losing $223 million in nine months against Commodore by selling its 99/4A computer as low as $99; such low prices likely damaged the reputation of the industry by making home computers appear to be inferior game machines. By contrast, IBM did not plan to sell through discount stores, and observers believed that many software companies would write applications for the new IBM computer without fearing that it would become orphaned quickly. George Morrow was one of the few to be pessimistic, predicting that Commodore's Jack Tramiel would "make mincemeat" of the "toylike" PCjr.
No longer facing a long-running antitrust suit by the United States government, IBM likely timed its announcement to hurt competitors' sales during Christmas although PCjr was not yet available. The company reportedly spent $40 million on advertising, which used Charlie Chaplin's iconic character "The Little Tramp", already used in a successful campaign for the PC, to link the two products together. Ziff-Davis, publisher of the successful PC Magazine, printed the first issue of PCjr Magazine even before the first units shipped; competitors included jr and Compute! for the PC and PCjr.
"One of the biggest flops in the history of computing"
When the PCjr became available in early 1984, sales were below expectations from the beginning, even with discounts. "Inventory is beginning to pile up", Time wrote in April, in part due to the launch early that year of the "exciting" Apple Macintosh. By December it stated that the PCjr "looked like one of the biggest flops in the history of computing...[it] sold as sluggishly as Edsels in the late 1950s".
At the PCjr's announcement, journalists reportedly "gasp[ed in] dismay" when they saw its chiclet keyboard, which had 62 keys versus the IBM PC's 83. The New York Times described it as "not suitable for serious long-term typing" and "nearly useless", PC Magazine reported hearing another comparing the keys' feel to "massaging fruit cake", and Compute! stated that the computer "leaves something to be desired. A keyboard for one". The magazine observed that "Atari and Coleco must have breathed collective sighs of relief, because both promptly raised January 1 pricing of their personal computer systems". BYTE called the keyboard "a new standard for intentional product handicapping", and other publications agreed that the keyboard was evidence IBM gave the PCjr less capability to avoid cannibalizing IBM PC sales. The design amazed competitors ("How could IBM have made that mistake with the PCjr?", one asked), and even IBM salespeople advised customers to buy a replacement keyboard.
|“||Junior is probably the most expensive product sold with the famous legend, "Batteries not included."||”|
—PC Magazine on the PCjr's wireless keyboard, 1985
The PCjr's cost was its biggest disadvantage, even more so than the keyboard; Ahoy! wrote that it, "a machine with relatively limited technology at a relatively high price, not only presented much less of a threat than the industry had feared", but benefited the Commodore 64 by encouraging Atari and Coleco to raise prices. IBM did not say whether the target market was the home, schools, or executives working at home, confusing software developers, but likely made a mistake by setting the PCjr's price in the $800–$1,600 range, where demand was weaker than for computers that cost less—especially the Commodore 64—or more. Norton warned that the PCjr "may well be targeted at a gray area in the market that just does not exist".
IBM was unfamiliar with the consumer market but hoped that customers would be willing to pay more for a product with, as an industry expert said, "those three letters". At $669 and up, however, the PCjr cost more than twice as much as the Commodore 64 and the Atari 8-bit family, while inferior to both and the Apple IIe for games; its price was close to that of the Coleco Adam, but the Adam also included a tape drive, a printer, and software. A basic package for playing games on a TV cost about $900, one for word processing with a thermal printer cost twice that much, and other packages cost $3,000 or more, even while IBM did not include batteries for the wireless keyboard.
The Apple IIe was the PCjr's most direct competition. Although the $669 PCjr model compared favorably to a $1,400 Apple IIe also with 64 KB and no floppy drive, Apple cut the IIe's price, offered a 30% discount to the important education market, and in April 1984 responded with the IIc, with 128 KB and a floppy drive. Although the PCjr's CPU was superior, the IIc had a much better keyboard, and the IIe and IIc's good sales compared to the PCjr implied that cost was not the latter's only problem.
Not fully PC compatible
Norton estimated that the PCjr had about 85% of the IBM PC's capability for a smaller fraction of its price. Nonetheless, many compared the PCjr unfavorably to the PC rather than to other home computers. IBM expected that most PCjr customers would be new to computers, but 75% were familiar with computers and wanted to run business software on it.
Many potential customers believed that the smaller computer could run most IBM PC software, and an important market for the PCjr was executives who took data home to work on. IBM technical documentation stated that the "PCjr is a different computer than the" PC, but "has a high level of programming compatibility"; it promised software developers that "if your application maintains an interface ... at the BIOS and DOS interrupt interfaces, then all hardware differences are handled transparently to your application". Norton expected that "any program that followed a design guideline of 64K and one disk drive is likely to run beautifully on the PCjr. That means that the PCjr will run most of the PC's programs nicely". He warned, however, that developers "must understand the PCjr's basic limitations and promise not to cheat", and predicted that applications that required more than 128K of memory, did not support using only one disk drive, or used IBM PC-specific copy protection, would have problems. In practice the PCjr proved incompatible with about 60% of PC applications including WordStar and two programs often used to test PC clones' compatibility, Lotus 1-2-3 and Microsoft Flight Simulator.
Limited hardware expansion
Along with the lack of software, computer dealers quickly identified the PCjr's limited hardware expansion capability as a major disadvantage. It only had an internal slot for a modem and an external slot on the right side for "sidecar" peripherals. IBM published technical details for the PCjr as it had done for the IBM PC to encourage third parties to develop accessories, but did not offer a second floppy drive, hard drive, or memory beyond 128 KB. Multiple sidecars proved very clumsy, and the computer required additional power supplies with a second floppy drive or several sidecars. The PCjr also lacked a DMA controller, so the 8088 CPU had to service standard system interrupts such as the serial port or the keyboard directly. The PCjr thus could not use modems faster than 2400 baud, and it would refuse to process keyboard input if its buffer was full or while the disk drive was in use.
|“||I want an Apple.||”|
—Child demonstrating PCjr at IBM event, when asked what computer she wanted for Christmas.
In July 1984—by which time PCjr sales had declined to only a few thousand a month—IBM replaced the chiclet keyboard for free with a new model with conventional typewriter keys. The act was unusually generous for the company, and the industry; one writer compared it to an auto maker sending four new free tires to its customers. (Other than the keycaps, the two keyboards were identical; IBM could have used the conventional design from the PCjr's debut.) IBM had to replace only about 60,000 keyboards, compared to the 250,000 to 480,000 computers that experts had estimated the company would sell during the first six months. IBM also reduced the PCjr's list price, offering a $999 package that was arguably superior to the comparably priced Apple IIe and IIc, while deemphasizing the PCjr's marketing as a home computer and emphasizing its ability to run IBM PC programs. What the company described as the most extensive advertising campaign in its history marketed the redesigned PCjr to customers. Advertisements listed the new price, "new typewriter-style keyboard", standard 128 KB of memory with new IBM-made expansion options to 512 KB, a new cartridge-based version of Lotus 1-2-3, and the ability to "run over a thousand of the most popular programs written for the IBM PC."
One large dealer stated in November 1984 that "it could be a PCjr Christmas", as the better keyboard and lower prices greatly increased demand; the computer reportedly outsold the Apple IIe and IIc by four to one in some stores. Sales declined again, however, when the discounts ended after Christmas, decreasing from an estimated 50 computers sold per store in December to 2.4 in February. By this time three PCjr-specific magazines had ended publication. With the overall home-computer market in decline—even while IBM could not meet the demand for its new PC AT business microcomputer—and likely unable to make a sufficient profit when the PCjr was sufficiently discounted to increase sales, the company discontinued it in March 1985 and, reportedly with more than 100,000 leftover PCjrs, sold them at a large discount to its employees.
|“||We're just sitting here trying to put our PCjrs in a pile and burn them. And the damned things don't burn. That's the only thing IBM did right with the machine—they made it flame-proof.||”|
Tandy Corporation released a clone of the PCjr, the Tandy 1000, in November 1984. Since the PCjr was soon discontinued, Tandy quickly removed mentions of the PCjr in its advertising while emphasizing the 1000's PC compatibility. The machine and its many successors were successful unlike the PCjr, partly because the Tandy 1000 was sold in ubiquitous Radio Shack stores and partly because it was less costly, easier to expand, and almost-entirely compatible with the IBM PC. The PCjr's enhanced graphics and sound standards became known as "Tandy-compatible", and many PC games advertised their Tandy support.
From mid-1985, what Compute! described as a "wave" of inexpensive clones from American and Asian companies caused prices to decline; by the end of 1986, the equivalent to a $1600 real IBM PC with 256K RAM and two disk drives cost as little as $600, lower than the price of the Apple IIc. Consumers began purchasing DOS computers for the home in large numbers; Radio Shack estimated that half of Tandy 1000 sales went to homes, not offices. The inexpensive clones succeeded with consumers where the PCjr had failed; unlike the IBM product, they were as fast as or faster than the IBM PC and highly compatible.
King's Quest, a popular adventure game series, was originally developed for the PCjr, as IBM had commissioned Sierra On-Line for a game that would take advantage of the PCjr's expanded graphics and sound capabilities (16-color 320x200 graphics and 3-voice+noise sound) for the product's launch.
IBM returned to the home market in 1990 with the IBM PS/1 line. Unlike the PCjr's departure from the IBM PC standard, the PS/1 line concentrated on IBM brand-name compatibility and affordability.
Several upgrades for the PCjr were designed by IBM/Teledyne but never reached the store shelves before the IBM PCjr was canceled. These included a wireless joystick and various memory/drive upgrades. PC Enterprises became the last of the major third party vendors to supply full service, parts, and add-ons, extending the functional life of the PCjr to about 10 years, often buying out inventory and rights for PCjr support.
- CPU: Intel 8088, 4.77 MHz
- Memory: 64K on the motherboard expandable to 128K via a card in a dedicated slot. Further expansion via IBM sidecar adapters. Later third-party add-ons and modifications raised the limit to 736K.
- Operating system: IBM PC DOS 2.10, (Boots to Cassette BASIC without cartridge or DOS)
- Input/Output: cassette port, light-pen port, two joystick ports, RGB monitor port, composite video port, television adapter output port, audio port, wired keyboard port, infrared keyboard sensor, serial port, two cartridge slots
- Expandability: 3 internal slots, dedicated to PCjr specific memory, modem (300 bits per second non-Hayes-compatible modem available from IBM, although 2400 bit/s Hayes-compatible modems were available from third parties), and floppy controller cards. External sidecar connector capable of daisy-chaining multiple sidecars.
- Video: Motorola 6845, "CGA Plus" This chip was officially called the VGA (Video Gate Array).
- Text modes: 40×25, 80×25, 16 colors
- Graphics modes: 320×200×4, 640×200×2, 160×100×16, 160×200×16, 320×200×16, 640×200×4
- Video memory is shared with the first 128 KB of system memory, and can be as small as 2 KB and as large as 96 KB.
- Sound: Texas Instruments SN76496; three voices, 16 independent volume levels per channel, white noise
- Storage: Optional 5.25 inch diskette drive or cassette. Other storage options were provided by third parties.
- Keyboard: 62 key detached. Corded or infra-red operation. IBM supplied two different keyboards, the first being the maligned 'Chiclet' keyboard, so named for its square rubber keys that resembled Chiclets. Many third-party keyboards were also available.
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IBM Personal Computer
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