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Digital Research’s new set of graphics software tools gives PCs a better view.

Reprinted from PC Magazine, December 25, 1984, pp. 35.

PACIFIC GROVE, Calif. – Digital Research hopes to add new sparkle to your PC – and its product line – with its new GEM. An acronym for Graphics Environment Manager, the new set of software tools can turn the screen of the lowliest PC into a vision of Apple’s Macintosh screen, complete with pull-down menus, icons, and mouse control.

A sample screen showing GEM’s use of icons, windows, and pull-down menus.
This image can be zoomedA sample screen showing GEM’s use of icons, windows, and pull-down menus.
With IBM promoting the yet-to-come TopView as the official standard for windowing on its personal computer line, and other like products – Microsoft Windows, Desq, Visi On, and Digital Research’s own upcoming Concurrent PC-DOS – still trying to best Big Blue, this news may seem to warrant nothing more than pointing your mouse at the trash can and pressing the button.

But you needn’t peer through a loupe to see that Digital Research’s GEM stands out from the others. A variety of on-screen type fonts and sizes reveal that GEM, like its Macintosh model, and like Microsoft Windows, is graphics-based, while most other PC windowing ducts use only the PC’s text-displaying abilities. However, rather than being able to manage two or more programs simultaneously in one computer, GEM is more like a toolkit of routines that programmers can use to create Mac-like application programs for the PC.

Compatibility Claim

In effect, GEM becomes an extension of the graphics-handling routines that IBM includes as part of the PC’s ROM BIOS (basic input/output system). In add-on applications on existing computers the GEM routines will be loaded into RAM (where they become resident, occupying about 60-80 kilobytes of memory) and get called up by other programs. In future machines, GEM can be hardwired into ROM chips.

Digital Research believes that GEM will claim a big stake in the PC software marketplace because it is uniquely compatible: Any program that runs under DOS should work with GEM without modification. There’s no need to run out and buy new, updated versions of your favorite software just to use GEM.

However, don’t expect to blow the dust off your favorite antique software package and expect GEM to give it state-of-your-dreams windowing abilities. Although GEM’s routines makes adding windows easy for programmers, they do not automatically confer windowing abilities on existing programs.

GEM’s underlying structure makes programs with Mac-like graphics easy to translate to a variety of different computer systems. GEM is constructed like DOS – or, more to the point, like Digital Research’s own CP/M operating system. Part of GEM, about 25 percent, is machine-specific code that must be rewritten and crafted for each model of computer GEM is implemented on, much like the BIOS of CP/M (or MS-DOS) is. The rest of GEM is universal, using the same code for the same results regardless of its environment. GEM applications call only to the universal part of the software, so they are very transportable – at least among machines for which GEM has been implemented.

Tinker Tools

More than just software-compatible, GEM is uniquely compatible with computer hardware because it requires little extra memory to operate. While true windowing systems start by chewing up a 256K chunk of memory and sometimes swallows 5 megabytes of hard disk just to get started, GEM can operate on systems as small as 128K – which includes the PCjr and lightweight compatibles.

The pull-down menu display that Digital Research has shown the world – a demonstration program that doesn’t do much more than show what the real GEM can do – is only a small facet of the whole GEM.

The menus operate as a shell or “front end” to DOS (in the familiar desktop metaphor form), so that, rather than typing in some cabalistic DOS incantation, you need only point to a command to carry it out. Programmers can use the GEM toolkit to write any number of similar shells for DOS, or they can use it to give menu structure to other programs.

Modest Mechanics

Unlike true windowing programs, GEM is not a multitasking system, and its ability to run programs concurrently is limited to the minimal background tasks that work with unadorned DOS.

Although you can “pull down” and run modest applications such as a memo pad or a calculator (for instance, in the demonstration menu system), you can’t use GEM to make Symphony, WordStar, PC-TALK, and dBASE III run simultaneously and slip each other love messages. That’s the job of GEM’s big (but still gestating) brother, Concurrent PC-DOS (as Digital Research would have it), or of TopView and the other windowing systems. According to Digital Research, the GEM routines are compatible with all windowing systems.


Don’t expect to find this GEM on your dealer’s shelves, however. It is not targeted for individual computer owners – at least for now. Instead, Digital Research is targeting hardware OEMs and software developers. In January, Digital Research will start selling GEM to software houses wanting to take advantage of this development system for a minimal fee of $400 to $500. That’s it – no recurring license fees, even though the GEM routines may be distributed with the finished software. Digital Research hopes that will tempt developers to get new, GEM-based software out on the market and help GEM to become a de facto software standard, much like CP/M.

In February, Digital Research will begin marketing GEM applications to consumers, including GEM-Draw, GEM-Word-Chart and GEM-Graph. But Digital Research’s pot of gold will be writing and licensing custom versions of the BIOS-like machine-specific part of GEM for hardware manufacturers. According to Digital Research, the customers are already lining up.

by Winn L. Rosch

Page added on 8th October 2004.

Copyright © 2002-2006 Marcin Wichary, unless stated otherwise.