Intel 80186 CPU: So misunderstood

Back when a 386 or 486 PC was hot stuff, I remember a common insult for a slow PC being, “What is that thing, a 186?” But no one we knew had a 186 PC, and no one really knew why either. In this blog, post, we will explore the Intel 80186, the CPU the PC industry forgot, why a misconception exists that it was a failure, and how both things can be true at the same time.

Although the 80186 powered two infamous PC-compatible flops in the early 1980s, a company founded by two Californians in a garage did use a 186-compatible CPU in a pioneering handheld computer about a decade later. Additionally, the 186 saw use in other embedded applications.

Why almost nobody used the Intel 80186?

There is a misconception that nobody used 186 CPU, at least in a PC. It wasn’t commonly used in PCs, but that’s not the same as saying nobody used it. There were indeed some noteworthy PCs that did use it. Not only that, they didn’t all fail in the market, either.

Tandy and the Intel 186

The most prominent early example may be the Tandy 2000. No, that is not a typo. 2000. Tandy advertised the 2000 fairly heavily, and even went to the expense of having Bill Gates as its pitchman.

Tandy positioned the 80186-based Tandy 2000 as the best computer for running Microsoft Windows. The problem was Microsoft Windows was about 5 years away from being useful. Like the 186 CPU, Microsoft Windows 1.0 is also something few people remember, if they knew it existed at all. I’ve had more than one person try to tell me Microsoft Windows wasn’t a thing in 1985. It was a flop, but technically speaking, a flop is a thing, isn’t it?

The Tandy 2000 was a flop, and not just because Windows wasn’t ready in 1983, and not ready for prime time in 1985 when it finally arrived. It ran MS-DOS, but it was nowhere near 100% IBM PC compatible. Software that stuck to using the standard BIOS routines for everything worked fine, but software that went around the BIOS and accessed the hardware directly tended to be problematic.

As a result, the Tandy 2000 failed. The Tandy 1000 wasn’t completely IBM compatible either, but it was much closer. It became a runaway success, and I argue Tandy was slow to embrace Windows 3.0 and 3.1 because the Tandy 2000 flopped so badly.

The Mindset

Another noteworthy 186-based PC was called the Mindset, released in May 1984. The Mindset, designed by a group of former Atari engineers headed up by Roger Badertscher, took an approach similar to the Tandy 2000, coupling a 6-MHz 186 CPU with advanced graphics and going after a new market. In the case of the Mindset, it went after the video editing market.

Although there were similarities in their approach, the Mindset and the Tandy 2000 used their own bespoke video standards that weren’t compatible with each other. In retrospect, cooperating on a new video standard may have helped both companies but also may have been impractical.

The Mindset is interesting because of its eye-catching industrial design, and Jack Tramiel considered buying or licensing the Mindset rather than developing the Atari ST.

The Mindset certainly was innovative, providing video editing capability that only an Amiga could match, but video editing was such a niche market at the time that it wasn’t enough to save the machine or the company. Mindset PCs are prized collectibles today.

80186-based machines in Europe

In Sweden, the 80186 saw use in a school computer called the Compis, which stood for COMPuter In School. It was also a play on the Swedish word Kompis, which means “friend.” It was also sold in Norway, Denmark, and Finland as the Scandis. Available from 1984 to 1988, its lack of 100% PC compatibility also subjected it to criticism, so it was discontinued in 1988, though existing units saw use into the 1990s.

In the United Kingdom, the 186 also saw usage in the Acorn/BBC Master 512, a successor to the famous BBC Micro released in 1986. Acorn sold it as an add-on to the Master 128 computer to add memory and an 80186 coprocessor. Acorn also sold the two bundled together. The Master 512 ran Digital Research’s DOS Plus on the 80186 CPU. Predictably, the result was somewhat, but not fully, IBM PC compatible. A cottage industry of add-on products to improve the Master 512’s PC compatibility appeared. Like so many other 186-based machines, however, the Master 512 struggled to compete against more conventional PC clones that offered near-100% compatibility and cost less.

HP 100LX and 200LX Palmtops

Even though 386 and 486 CPUs were the rage by the early 1990s, the 186 experienced a resurgence as a PC CPU in 1993 and 1994 when HP built a pair of handheld products around an 80C186-based SOC called the Intel SB60168, or Hornet. These tiny PCs, the HP 100LX and 200LX, fell into a product category called palmtops. Palmtops were PCs comparable in size to a modern smartphone, ran MS-DOS, and the 100LX and 200LX could even run Windows 3.0 in a pinch. More importantly, they came with popular DOS programs like Lotus 1-2-3 and Quicken built into ROM. For someone who found stylus-based machines like the Apple Newton or the Palm Pilot awkward, an HP Palmtop provided a mobile computing experience much closer to that of a conventional PC.

HP didn’t invent the Palmtop. That credit belongs to Atari, who released the Portfolio computer in 1989. But HP leveled up the concept.

The 186 made sense for this use case because it gave an excellent combination of performance, battery life, size, and cost. 100% compatibility was less of a concern because the systems were so small. The target market was someone who just wanted to read e-mail, balance a checkbook, reference a spreadsheet, or proofread documents on the go and sync the data with a full-size PC later. HP bundled those apps in ROM, so it was OK if it differed slightly from the versions on regular PCs.

And by 1993, DOS software tended to be more tolerant of minor incompatibilities between hardware. That meant a surprising number of 1990s DOS programs ran fine on HP’s 186-based palmtops when someone needed to run something other than one of the bundled apps on them.

But no one used them, right?

HP Palmtop systems didn’t sell in desktop PC-like numbers, because portable computing was very much a niche at the time. So success was relative. The 1991 model 95LX used an NEC V20 CPU, but the later 100LX and 200LX models used the Intel 80186-based SB60168. These machines cost around $800 when new. Maybe they weren’t hip or chic, but they were practical. And HP kept the 200LX on the market up to the edge of the millenium, discontinuing them in 1999. Sales figures are hard to pin down but the machines readily available on Ebay, which indicates they aren’t rare and therefore sold well.

Palmtops never had the buzz of the Newton or the Palm Pilot. And if someone was using it, it looked like they were just using a calculator. These things made them easier to escape attention. Nevertheless, HP Palmtops quietly developed and retained a devoted following, much like the TRS-80 Model 100 did.

While the Newton missed sales expectations by 85 percent, HP cried all the way to the bank, selling palmtop PCs into the early 2000s. Windows 95 and 98 weren’t practical in this form factor, but Windows CE was, so post-1999 HP Palmtops used RISC CPUs and Windows CE. Even after their time on the market came to a close, the 186-based palmtops retained a following for people who preferred MS-DOS.

Was the Intel 80186 CPU a failure?

Part of the reason systems based on the Intel 186 had poor IBM compatibility was because Intel integrated the clock generator, timer, and interrupt controller onto the CPU itself. Intel did similar integrations several times over the years, and it helped to increase performance while driving down cost. But this was a pretty innovative move for 1982.

The problem was that Intel integrated those components in a way that was incompatible with the IBM PC. In retrospect, that seems like such an obvious mistake that no one would make it.

The IBM PC’s unexpected success

It helps to know the IBM PC hit the market in August 1981, only a few months before the 80186 CPU. Not only that, the IBM PC’s immediate success took everyone, including IBM, by surprise. Byte magazine’s January 1983 issue noted that between August 1981 and February 1982, the IBM PC sold 60,000 units. IBM expected to sell ONE thousand units in that timespan.

Don’t get me wrong, no one expected the IBM PC to fail. But it caught on faster than anyone reasonably expected.

The IBM PC and the Intel 80186 were being developed in parallel, and at the time, it wasn’t at all clear how necessary 100% compatibility with the IBM PC would be. It’s likely that Intel told IBM about the 186, but there’s no question IBM didn’t want to wait for it. One of the reasons IBM went with the 8088 in the first place was because it was ready to go in 1980 when IBM started developing the PC. Clone makers who wanted to make a faster PC than IBM had better success going with an 8086, a faster-clocked 8088, or an NEC V20. Eagle and Compaq were two examples of companies who made 8086-based XT clones. Leading Edge was a good example of an XT clone that used an 8088 clocked at a higher rate than IBM’s 4.77 MHz.

The Intel 186 in non-PC applications

The 186 saw extensive use as an embedded processor in PC and non-PC applications. Yes, sometimes peripherals for PCs like SCSI controllers used 186 CPUs onboard. For these other uses, the 186 was extremely successful. It sold so well for non-PC use early on that Intel struggled to keep up with demand for the 186. Intel continued producing it until 2007, a 25-year lifespan.

The 186 didn’t get the publicity the 8088, 286, and 386 did. And Intel seemed to realize the 186 wasn’t going to be for everyone, because the 286 CPU hit the market in February 1982. The 286 did see extensive use in PCs. Like the 186, there were some PC-like 286-based computers that appeared in 1982 and 1983. But sales really took off starting in August 1984, when IBM released the PC/AT. The 286 sold well until 1991, when sales tailed off due to the success of Windows 3.0 and 3.1.

So while there’s a reasonably good chance you’ve never used a 186 CPU in a PC before, you probably have used other devices with 186 CPUs in them over the course of your life, just without realizing it.

Computer chips usually don’t have theme songs. But if the Intel 80186 had a theme song, it would probably be “Misunderstood” by Wilco, the first track on their 1996 album Being There.