Compaq Portable 286
| Industry | Computer hardware |
|---|---|
| Founded | November 1982 |
Area served | Worldwide |
| Products | Compaq Portable series |
The Compaq Portable stands as one of the earliest portable computers compatible with the IBM PC architecture and marked the debut product for Compaq Computer Corporation. Its BIOS was reverse-engineered, paired with a version of MS-DOS closely mirroring IBM's PC DOS, which ensured extensive software compatibility with IBM PC programs. This strategic design established Compaq as a frontrunner in the nascent market for portable IBM PC-compatible devices.
Although it arrived two years after initial CP/M-based portables such as the Osborne 1 and Kaypro II, and shortly following Columbia Data Products' MPC 1600—the first system compatible with the IBM PC—the Compaq Portable distinguished itself by delivering full IBM PC compatibility. Rival products like Dynalogic's Hyperion, Eagle Computer's Eagle 1600 series, and Corona Data Systems' personal computer encountered legal disputes over BIOS copyright violations, resulting in expensive redesign efforts. Compaq circumvented these issues by meticulously reverse-engineering the BIOS, allowing it to fully leverage the expanding demand for IBM-compatible machines.
Other contemporaneous portable computers included the Commodore SX-64, a briefcase-sized adaptation of the Commodore 64 equipped with an 8-bit MOS 6510 processor and a color display. Nevertheless, these alternatives could not rival Compaq’s comprehensive IBM-compatible portable lineup, which set the benchmark for portable business computing in the early 1980s.
Production and sales
Announced in November 1982 and released in March 1983, the Compaq Portable was initially priced at for a model with a single half-height " diskette drive or US$3,590 for configurations featuring two full-height drives. Weighing , it folded into a carrying case comparable in size to a portable sewing machine.
In response, IBM launched the IBM Portable PC to directly challenge Compaq’s product. During its first year on the market, Compaq sold 53,000 units, generating in revenue—a record for U.S. business at that time. Revenue increased to in the second year and further rose to in year three, consecutively setting new industry records.
Design
The hardware of the Compaq Portable closely mirrored that of the IBM PC but incorporated Compaq’s own BIOS. Its luggable case was designed to meet airline carry-on size requirements. Each unit shipped with 128 KB of RAM and one or two double-sided, double-density floppy drives capable of storing 360 KB each. The system operated exclusively on AC power without battery support.
Its display combined the high-quality text mode (80x25 characters) from the IBM MDA with CGA’s graphical capabilities. Users could toggle between an internal monochrome monitor (utilizing a 9×14 character font) and an external monitor (with an 8×8 font) through a keyboard shortcut. The graphics subsystem was also employed in Compaq’s Deskpro desktop series.
The keyboard featured "foam and foil" contact pads manufactured by Keytronics, similar to those used in other prominent systems like the Apple Lisa and Compaq Deskpro 286 AT. Over time, these foam pads were prone to deterioration. The CRT screen exhibited a low refresh rate accompanied by noticeable ghosting effects.
Software
Compaq’s achievement was largely due to IBM’s reliance on mostly off-the-shelf components and publicly available technical specifications, combined with Microsoft’s licensing of MS-DOS to various manufacturers. The primary obstacle was replicating IBM’s BIOS, which contained proprietary code. Compaq solved this by developing a clean room BIOS clone that duplicated all IBM PC BIOS functionality while using entirely original code.
Although many companies later marketed PC-compatible systems, few matched Compaq’s near-total software compatibility with the IBM PC until Phoenix Technologies and others began offering commercially available reverse-engineered BIOSs.
Initial Portables ran on Compaq DOS 1.10, nearly identical to PC DOS 1.10 but including a standalone BASIC interpreter; this was later superseded by DOS 2.00 which introduced support for hard disks among other enhancements.
Early models resembled IBM PCs but had BIOS limitations such as support for only up to 544 KB RAM and no expansion ROM capability, restricting compatibility with hardware like EGA/VGA cards or hard drives. Following DOS 2.x releases and the launch of the IBM XT, Compaq updated its BIOS accordingly. Though not originally equipped with hard disks from the factory, many users installed them later. In 1984, Compaq released the Portable Plus model featuring a hard disk (ranging from 10 to 21 MB) alongside a half-height floppy drive.
The Portable 286 debuted in 1985 but was swiftly succeeded by the more compact Portable II featuring a redesigned chassis. The Portable 286 came with a full-height hard drive and offered flexible drive configurations including floppy drives and tape backup options.
Reception
BYTE commended the Compaq Portable for its ease of transport, affordability, and strong compatibility with IBM PC software after evaluating several programs—only one game failed to run properly. InfoWorld described it as "a highly practical and well-priced device tailored for professional applications." Meanwhile, PC Magazine emphasized its durable construction, crisp screen quality, and comprehensive software support, recommending it to users who required IBM PC functionality without purchasing an IBM machine.
Compaq Portable Plus
Introduced in 1983, the Compaq Portable Plus enhanced the original model by substituting one floppy disk drive with a hard drive, and it featured distinctive gold-toned logos and badges. This strategy addressed a consumer need that had previously been fulfilled by third-party vendors, thereby generating direct revenue for Compaq.
Compaq Portable 286
The Compaq Portable 286 represented Compaq’s version of the PC AT, utilizing the initial Portable case while incorporating a 6/8 MHz 286 processor alongside a fast 20 MB hard drive.
Compaq Portable series
The original Compaq Portable spawned a lineup of successors, including the more compact, lighter, and cost-effective Compaq Portable II, which offered fewer upgrade options and a slower hard drive. Later iterations comprised the Compaq Portable III, Compaq Portable 386, Compaq Portable 486, and Compaq Portable 486c, each delivering gradual enhancements in performance and features.