IBM PCjr
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Image:IBM logo.svg The IBM PCjr was IBM's first attempt to enter the markets for relatively-inexpensive educational and home computers.
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Features
Announced November 1, 1983, and first shipped in March 1984, the PCjr came in two models: the 4860-004, with 64K of memory, priced at US$669; and the 4860-067, with 128K of memory and a 360K 5.25-inch floppy disk drive, priced at US$1269. The PCjr promised a high degree of compatibility with the IBM PC, already a popular business computer, and offered built-in color graphics and sound comparable to or superior to other home computers of the day. Additionally, its 4.77 MHz Intel 8088 CPU was faster than other computers aimed at the home market, and its detached wireless infrared keyboard promised a degree of convenience none of its competitors had. Two cartridge slots promised easy loading of games and other software.
The PCjr's code name was "peanut", and it was referred to as such by several trade magazines.
The popular 1980s adventure game series King's Quest 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 for the product's launch.
Failure in the marketplace
The PCjr launched with an enormous amount of advance publicity, including live news-broadcast coverage of the product announcement. Ziff-Davis, publisher of the successful PC Magazine, printed the first issue of PCjr Magazine even before the first PCjr units shipped. Observers expected the PCjr to change the home-computer market in a similar way to how the IBM PC had singlehandedly changed the business market in the two years since its debut.
However, the PCjr was never well received. A prime target of criticism was its keyboard; IBM chose to use a chiclet keyboard, similar to that of a pocket calculator, with wide spaces between keys to leave room for instructional overlays bundled with software packages. However, it was widely criticized as feeling cheap and being difficult to type on. IBM eventually replaced it for free with a conventional keyboard. Regardless of the keys' design, with only 62 keys, it lacked the numeric keypad and separate function keys of the IBM PC, and the layout was more awkward than that of most of its competitors. In addition, the wireless functionality did not work as well as expected; in practice, range only extended to about two or three feet from the machine, and batteries drained very quickly.
At $669, the PCjr's price was not competitive. It cost more than twice as much as the Commodore 64 and the Atari 8-bit family; its price was close to that of the Coleco Adam, but the Adam also included two tape drives, a printer, and software. With the exception of the Apple II, it was possible to purchase a complete system (computer, disk drive, printer, and monitor) from almost any of IBM's competitors for less than the PCjr's entry price.
Many people compared the PCjr unfavorably to the IBM PC rather than to the machines against which it was directly competing. While compatibility with the IBM PC's large software library was a key selling point, in practice the PCjr proved incompatible with many popular PC applications, in part due to memory limitations and in part due to architectural differences.
Arguably, the PCjr's technical capabilities may have justified its higher price tag: it was a 16-bit machine competing in an 8-bit world, offered better memory expansion, had a built-in 80 column display, and was faster than any of its competition. However, reviewers of home computers at the time cared much less about raw power and more about price, available software, and the quality of the keyboard. Moreover, while the PCjr may have been superior to its competitors in running office suite software, it was clearly inferior to the Commodore 64 and the Atari 8-bit family as a gaming platform; unlike them, it had very limited color capabilities (due to its CGA-derived graphics chip) and no support for hardware sprites. Also, the sound chip was nowhere near as advanced as the MOS Technology SID found in the C64 (although it rivaled Atari's POKEY). Since gaming capabilities were important to many home computer buyers of the time (who often purchased the machines as replacements for older game consoles), this was another strike against the PCjr.
The PCjr was more difficult to expand than many of its intended competitors. It was not designed to add a second floppy drive, a hard drive, or easily expand memory beyond 256K, which made it difficult to deliver on the promise of running business software for the IBM PC. Add-ons to provide a second floppy drive or a 20-megabyte hard drive were only available from third parties, and these were not available right away. Many IBM and third-party add-ons attached to an expansion slot on the computer's right side, similar to the design of the discontinued TI 99/4A; thus, as with the TI, multiple add-ons proved very clumsy.
Unable to compete with the C64 and Apple Computer's IIe and IIc, let alone the forthcoming Atari ST and Commodore Amiga, IBM withdrew the PCjr from the marketplace in mid-1985.
The PCjr legacy
Tandy produced a clone of the PCjr, the Tandy 1000. Since it was released two weeks after the PCjr was discontinued, Tandy had to hastily change its marketing strategy. However, the machine and its many successors ultimately proved much more enduring than the PCjr itself, 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. Ironically, the enhanced graphics and sound standards the PCjr pioneered ultimately became known as "Tandy-compatible" or "TGA."
IBM returned to the home market in 1990 with its much more successful IBM PS/1 line. The words "IBM compatible" carried much more marketing weight in 1990 than they did in 1984.
Technical specifications
- CPU: Intel 8088, 4.77 MHz
- Memory: 64K on the motherboard expandable to 128K via a card in a dedicated slot. 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, lightpen 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 memory, modem, and floppy controller cards. External sidecar connector capable of daisy-chaining multiple sidecars.
- Video: Motorola 6845, "CGA Plus"
- Text modes: 40x25, 80x25, 16 colors
- Graphics modes: 320x200x4, 640x480x2, 160x100x16, 160x200x16, 320x200x16, 640x200x4
- Video memory is shared with the first 128K of system memory, and can be as small as 2K and as large as 96K.
- 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. Many third-party keyboards were also available.de:IBM PCjr