16-bit Processors – 1981-86: Intel vs. Motorola

Most manufacturers sold 8-bit and 16-bit machines in the 1980s. I thought it would be useful to distinguish the important 16-bit models of the early 1980s to help explain their historical significance.

Since the mid 1970’s American microcomputer manufacturers had been selling personal computers with 8-bit microprocessors (such as the MOS 6502, Motorola 6800, Intel 8080, and Zilog Z80). These microprocessors were responsible for launching the personal computing revolution. These systems continued to sell very well into the 1980’s, but the 8-bit world would soon be dwarfed by IBM’s 16-bit Intel 8086 PC (model 5150, fall 1981), followed by the Apple Macintosh (Jan 1984), a dual punch industry disruption rivaled perhaps only by the launch of the appliance computer in 1977 itself.

The IBM PC was introduced in the fall of 1981 and within two years companies like Compaq, Panasonic, NEC, Televideo, Toshiba, GRiD, and Tandy joined in to sell “clones” of their own with 16-bit Intel 80×86 microprocessors. IBM clones were machines based on the IBM PC standard whose hardware, software and files could be copied and read interchangeably (“a clone”). These were number crunching machines built to generate and print business proposals with color graphs and charts, manage databases, and automate document processing. 16-bit Local Area Networks emerged (Banyan/Novell). The PC revolutionized office productivity. The Intel / PC computer replaced the typewriter on thousands of secretary’s desks across the USA and Worldwide. Small business computer manufacturers who did not embrace the IBM PC standard were forced out of business. The IBM PC stalled the advance of Japanese computer manufacturers into the American market, due to their delayed adoption of MS DOS and incompatible systems.

Most IBM PC / clone users favored the text-based the Microsoft / IBM DOS operating system, a quick efficient interface with many features. MS DOS included a powerful batch scripting language which was used to produce menus and perform complex file operations. A file produced in one MS DOS computer could be copied to disk and read on another MS DOS computer without conversion. MS DOS also introduced subdirectories (i.e “folders”) to personal computing. MS DOS was easier to learn compared to CP/M, which had been the dominant OS for small business computing before the IBM PC. The programming language C++ became popular on the IBM PC platform for the development of a plethora of applications. The open nature of the IBM PC encouraged the development of a software industry dedicated to this platform. Software like WordStar, WordPerfect, Lotus 1-2-3 and dBASE III could be installed on any MS DOS PC with enough hard disk and RAM to load and run them.

LEFT: 1983/4 IBM 3270 PC with Intel 8086 CPU and 8087 Co-Processor. This computer was an enhanced IBM XT made for the 1980’s office network. As a terminal, the 3270 was used to connect like a “dumb terminal” to an IBM mainframe to access services such as PROFs email or the mainframe’s TSO/JCL environment. In “local” mode the 3270 could run word processing software such as IBM’s DisplayWrite 3 or Lotus 1-2-3 stored on its 20mb hard drive. RIGHT: The 1985 Amiga A-500 was a Motorola 68000 CPU home computer designed for games, MIDI / sound processing and home office applications. Hundreds of arcade games were ported to the Amiga format without loss of quality, unlike the watered-down 8-bit versions.

Apple, Commodore and Atari were already well known manufacturers of 8-bit computers. Looking to stay relevant in the new 16-bit world, these companies set out to produce their own 16-bit machines, which they all believed should feature a mouse / graphical user interface (GUI). Apple in particular believed the GUI would eventually become the industry standard despite their limited niche market at the time. Contemporary systems using a GUI at the turn of the 80’s were too expensive for home use.

It was a reasonable strategy for Apple, Atari, and Commodore who already had lower-priced 8-bit computers to develop high-end M68000 systems as a way to expand into new markets, while avoiding direct competition with IBM and the Intel clones or cannibalizing their 8-bit product line. Apple and others selected the Motorola 68000 microprocessor in order to develop a GUI system for less than $5000, which was within the budget of small business, especially in the new desktop publishing market. Further, the 680×0 was excellent for audio (MIDI) and peripheral support. Apple, Commodore, and Atari also set out to develop systems dedicated to computerized audio/video production. They wished to supplant analog audio studio equipment and take on the expensive minicomputer-driven digital audio system sold by companies like Digital Equipment Corp and others.

Leading the way were Apple’s Lisa and Macintosh. Borrowing from the XEROX Alto, Apple helped launch the PC-based desktop publishing industry and established the mainstream GUI/mouse standard still in use today. Meanwhile Atari installed the Motorola processor in its ST model, whose operating system featured the first bitmapped GUI in a home computer. In 1985 Commodore teamed up with Atari to produce the offshoot company Amiga. Amiga produced M68000 computers with an well-received GUI interface, graphics, and audio processing.

It would be a while before Motorola-based computers would compete with Intel-based computers in the world of office productivity software, but we can save the MS Windows – Macintosh – OS/2 story for another day.

In the 1981-86 timeframe Intel-based machines out-sold Motorola systems 10-fold, despite the advanced graphics and audio of the latter. This was mostly because the market for 16-bit office productivity was a lot larger than the hi-end PC gaming / desktop publishing markets. Consider also that 8-bit home computers were good enough for many, and a lot cheaper. Case in point – One might think the Macintosh was an immediate success, but in 1984 it was too expensive and too under-powered to sell well. Macintosh software lacked important features. It was to many more a “proof of concept” than a practical computer. Ironically if Apple has not chosen to spend some of its 8-bit Apple II profits on the Macintosh project, it may never have been supported long enough to become profitable in its own right. Any other company would not have had the patience to hold out for as long as was needed to keep up with it. The superior GUI/mouse interface was interesting and fun but it was not yet the must-have killer ap for the typical PC user. Most customers were content enough with the likes of Tandy’s blocky text block-based DeskMate GUI which was cheaper and ran Intel 8086 XT office applications such as WordStar and Lotus 1-2-3. It is well known that the first thing many PC users did with their new computers if they booted into a file manager GUI was disable it entirely, opting for the C:\> prompt to run their programs.

But that did not mean everyone read the market correctly. AT&T manufactured a Motorola-based system called the “UNIX PC” with a text-based GUI, monochrome graphics, and very high price tag. Despite its superior CPU performance and UNIX operating system, it was a flop in the market. Similar to Apple’s Lisa, the AT&T UNIX PC may have been too far ahead of its time. Unlike Apple, AT&T did not follow up with a more marketable computer (Apple replaced its Lisa with the Macintosh). In fact, UNIX on a PC did not gain traction in the PC market until Intel 386 systems became the PC standard in the late 1980’s. Interestingly no market successful 68000 system with a GUI *and* UNIX appeared until later in the decade. UNIX did not become mainstream until the appearance of more powerful computers by SGI, NeXT, and DEC arrived. But that’s a different room in the museum…

ABOVE: The Commodore 1985 Amiga A-500 with Express sidecar hard drive. The program loaded on the screen is called AAARGH!. This computer featured excellent MIDI sound processing capability. In the mid 1980’s the Amiga was considered the best multimedia PC for the money, out-pacing the competing Apple’s 16-bit IIGS and Atari’s 16-bit computer, the ST. The Apple Lisa and Apple Macintosh were too expensive and did not offer color graphics until later in the decade.

FACTOID: Did you know that Texas Instruments’ 1979 TI-99 4/a had a 16-bit CPU (TI9900)? Most people don’t count this as a true 16-bit machine because of the way the microprocessor bus was designed but we’d be remiss to not mention this fact here.

FACTOID #2: The Sage II was one of if not the first Motorola 68000 PC workstation. It went to market about six months after the IBM PC and was intended to compete against it. The system required a serial terminal for I/O and it ran a SAGE version of UCSD Pascal or CP/M 68000. A lack of graphic support and a high price-tag killed this machine’s chances for mass appeal. If the 68000 had been available 6 months earlier, perhaps the IBM PC may very well have been built around this architecture instead of the 8088/8086….an interesting thought experiment to consider what kind of machine that would have been!