Data General-One

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A Data General One laptop computer

The Data General-One (DG-1) was a portable personal computer introduced in 1984 by minicomputer company Data General.

Description[edit]

The nine-pound battery-powered 1984 Data General One ran MS-DOS, had dual 3½" diskettes, 79-key full-stroke keyboard, 128K to 512K of RAM, and a monochrome LCD screen capable of either the standard 80×25 characters or full CGA graphics (640×200). It was a laptop comparable in capabilities to desktops of the era.

History[edit]

The Data General One offered several features in comparison with contemporary portable computers. For instance the popular 1983 Radio Shack TRS-80 Model 100, not a PC compatible machine, was comparably sized. It was a small battery-operated, computer resting in one's lap—but had an 32x8 character (240x64 pixel) screen, a rudimentary ROM-based menu in lieu of a full OS, and no built-in floppy. IBM's 1984 Portable PC was comparable in capability with desktops, but was not battery operable and being much larger and heavier was by no means a laptop.

Drawbacks[edit]

The DG-1 was only a modest success. One problem was its use of 3½" diskettes. Popular software titles were not thus widely available (5.25" being still the standard), a serious issue since then-common diskette copy-protection schemes made it difficult for users to copy software into that format.

Although the CPU was a CMOS version of the 8086, compatible with the IBM PC's 8088 except it ran slightly slower, at 4.0 MHz instead of the standrd 4.77 MHz.

Unlike the Portable PC, the DG-1 laptop could not take regular PC/XT expansion cards.

RS232 serial ports were built-in, but the CMOS (low battery consumption) serial I-O chip available at design time, a CMOS version of the Intel 8251, was register incompatible with the 8250 serial IC standard for the IBM PC. As a result, software written for the PC serial ports would not run correctly. This required the use of software written using the relatively slower and less flexible BIOS interrupt call (014h), or software written exclusively for the DG-1.

Video memory came out of that available for the operating system; if 256 kB of RAM was installed only 204 kbytes might be available to the operating system and user's programs.

Although Creative Computing termed the price of US$2895 "competitive,"[1] it was a very expensive system and usually-needed additions such as more RAM and an external 5¼" drive drove the price higher yet. The styling of the product, including a bag designed by Pierre Cardin, implied a more up-market buyer than many of the typical PC buyers of the time. The Data General One also had a built-in dumb terminal emulator, suggesting an attempt to attract as customers those in organisations with large, expensive minicomputers or mainframes that would access corporate data via terminals such as the ADM-3A or Data General's own Dasher terminals (the cost of the laptop would not have seemed excessive in such situations).

But the Achilles heel was the LCD display itself, which was not backlit, and had low contrast which was slightly enhanced by blue characters on a yellow background.

References[edit]

  1. ^ Data General/One, Creative Computing Volume 11, Number 01 (January 1985), p. 55