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Before the PC: Remembering Kaypro and Osborne Computers

We didn’t always live in a Windows and Mac world. Before the IBM PC, before the Apple Macintosh, there were pioneering personal computers from companies like Kaypro and Osborne. In this article, old-timer Michael Miller steps into the Way Back Machine to take a look at the CP/M operating system, the Osborne 1, and the Kaypro II. It was a different world back then!
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Before there were IBM and Compaq, before there were MS-DOS and PC DOS, there were two companies selling primitive microcomputers to businesses and hobbyists, both running a now-obscure operating system called CP/M. Those companies – Osborne Computer Corporation and Kaypro Corporation – and their namesake computers had a tremendous impact on the now ubiquitous personal computer market, and are fondly remembered by pioneering computer users of the time.


It all started with the operating system. Most techies are familiar with the story of how Bill Gates and his accomplices developed (or stole, depending on which version of the story you believe) the Disk Operating System, or DOS, for IBM to use in its initial personal computers. But DOS, in both its MS-DOS and PC DOC variants, was not the first operating system for desktop computers.

That distinction belongs to the CP/M operating system. CP/M stands for Control Program for Microcomputers (originally Control Program/Monitor), and was developed by Gary Kildall of Digital Research, Inc., in 1973-1974.

The original version of CP/M was a single-tasking OS for 8-bit processors, and could utilize up to 64KB of memory. Later versions of CP/M added multi-user capability and the ability to work with 16-bit processors.

CP/M looked a lot like DOS, in that it utilized a character-based (non-graphic) interface. To perform any task, you had to use the keyboard to enter the appropriate command at the prompt. That required an intimate knowledge of dozens of essential commands, or a handy dandy command reference of some sort. (This was before the era of computer book publishing – several years before Que published its first books, in fact.)

There were a number of popular productivity programs written for computers running CP/M, including WordStar (word processor), Multiplan (spreadsheet), dBASE (database), and AutoCAD. In addition, a number of widely-used programming languages of the time – including BASIC, FORTRAN, and Turbo Pascal – were available in CP/M versions.

CP/M quickly became the industry standard OS for the microcomputers of the late 1970s/early 1980s. It was widely used in both home- and business-oriented computers, including the Altair 8800, Atari 800, AT&T 6300, BBC Micro, Commodore 64 and 128, DEC Rainbow, Epson PX-4, NEC PC-8001, Tandy TRS-80, Texas Instruments TI-99/4A, and ZX Spectrum +3, – and, of course, the Osborne 1 and Kaypro series of computers.

The Osborne 1: The First Successful Personal Computer

Back in the late 1970s, personal computing was essentially a hobbyist's endeavor. There were "toy" computers such as the Commodore 64 and TI-99/4A, as well as higher-end projects such as the TRS-80 and ZX Spectrum. There were even a few microcomputers pitched at the business market, although none really reached a critical mass in sales.

Into this environment marched Adam Osborne, former book and software publisher. His company published some of the first computer books before it was acquired (in 1979) by the larger McGraw-Hill publishing company. (The computer book publishing unit is now known as Osborne/McGraw Hill.)

Osborne was also somewhat of a computer hobbyist, known to frequent meetings of the famous Homebrew Computer Club. In April, 1981, his new company, Osborne Computer Corporation, released its first microcomputer. The Osborne 1, as it was called, was designed by Lee Felsenstein, based loosely on Xerox's NoteTaker PC prototype. It ran the CP/M operating system and cost just $1,795 – a bargain compared to similar microcomputers of that era.

The Osborne 1 resembled nothing more than an hard-sided suitcase. It weighed 23.5 pounds and came with a built-in keyboard (that also functioned as the unit's fold-down lid) and tiny 5-inch monochrome CRT monitor that displayed 52 characters by 24 lines. It was called a portable and, in the sense that it was a relatively compact all-in-one unit, could function as such -- although that weight made it more of a luggable. Let's be kind and just refer to it as a suitcase computer.

Figure 1 The Osborne 1, circa 1981. Photo by Bilby (Own work) [CC-BY-3.0 (http://creativecommons.org/licenses/by/3.0)], via Wikimedia Commons

Technology-wise, the Osborne 1 didn't really break much ground. It ran a 4 MHz Z80 CPU, with 64Kb main memory, and included a single IEEE-488 port configurable as a parallel printer port. Like other computers of the time, the Osborne 1 used two single-sided/single density 5 1/4" floppy disks. It did not include a hard disk; those would not become common for another year or more. As such, users had to do a lot of disk swapping to load programs into memory (from one diskette) and then access data (from another disk).

Software-wise, the Osborne 1 included a large bundle of popular productivity software, almost equal in value to the price of the computer alone. The software included WordStar, SuperCalc, and (later in production) dBASE II.

The Osborne 1 was an immediate critical hit. InfoWorld gave it a front-page article, while BYTE wrote "There are two particular interesting points about this computer: (1) it will cost $1795, and (2) it's portable!" Tech writer Jerry Pournelle wrote that "You can't beat it for the price, under $2000 bucks with over a thousand dollars' worth of software."

It also sold a lot of units for the day. In its first eight months of release, the company sold more than 11,000 units of the Osborne 1. At its peak, the company was selling close to 10,000 units per month.

Many early computer users earned their stripes at the fold-down keyboard of an Osborne 1. It wasn't a particularly enjoyable experience – that 5-inch screen was painful to look at for extended periods of time, and all that floppy swapping got old real fast – but it did put significant computing power in the hands of businesses and individuals at what was then a relatively affordable price. The Osborne 1 truly pioneered the era of desktop computers for productivity.

With every success, however, comes competition – the chief of which was a model that looked a lot like the Osborne 1, at a similar price and with similar bundled software, but with a bigger display and more storage capacity.

Kaypro: Competition Comes in Small(ish) Packages

Andrew Kay was an engineer and the founder of Non-Linear Systems, a digital instruments manufacturer. While there he invented the digital voltmeter – and later came up with the idea of a personal microcomputer to compete with the Osborne 1. The Kaypro Corporation was created to design and market these computers, and met with tremendous initial success.

Kaypro's first market-ready computer, in 1982, was called the Kaypro II. (The Kaypro 1 never made it to market.) Like the Osborne 1, it was a "portable (in name only) that ran CP/M on a 2.5 MHz Z80 CPU, with 64 Kb of RAM. It featured a fold-down keyboard and built-in monochrome CRT display, and weighed 29 pounds. It also came bundled with a lot of expensive productivity software (Perfect Software's office suite of PerfectWriter, PerfectCalc, PerfectFiler, and PerfectSpeller) at a comparable $1,795 price.

The Kaypro II upped the ante, however, with a larger 9-inch screen with 80 column display. In addition, it included single-sided/double-density 5 1/4-inch disk drives, which doubled the storage capacity of the Osborne 1. It also featured an aluminum case, which appeared more rugged than the Osborne's plastic case.

Figure 2 The Kaypro II, circa 1983. By User:Hstoff (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

A year or so later, the company revamped the Kaypro II with half-height drives and simple block-style graphics. This version came bundled with WordStar, SuperCalc, and dBASE II, as well as then-popular Space Invaders game. The company also cut the price to $1,595.

Those added features  resulted in unprecedented sales for the Kaypro II. The company was selling more than 10,000 units per month, and the unit's popularity inspired a network of Kaypro-based user groups across the U.S. It also helped to kill sales of the competing Osborne 1.

The Kaypro II was the first personal computer I used for productivity purposes. (I'd used the Commodore VIC 20 and 64, but those weren't really productivity machines.) We were looking for a business-oriented machine for my father's retail business, and our choices were the Apple II (not businessy enough), the IBM PC (not yet proven), and the Kaypro II/Osborne 1 machines. The Kaypro seemed to be the best bargain of the bunch, so that's the way we went.

I ended up spending untold hours in front of that 9-inch green screen, creating newsletters with WordStar and managing inventory with dBASE II. Yeah, I did a lot of floppy swapping (the dBASE program was on one disk and the inventory file on another), but the machine worked surprisingly well and did exactly what I needed it to do. I also think the Kaypro's firm and clicky keyboard outshone the Chiclet keyboards we have today.

Anyway, the success of the Kaypro II let to the introduction of several follow-up models. In 1983, the company introduced the Kaypro IV, with increased-capacity double-sided/double-density floppy drives. The same year saw the release of the Kaypro 10, one of the first computers to feature hard disk storage – in this instance a whopping 10MB hard drive. Additional models followed, including the Kaypro Robie, a non-portable jet-black desktop model that some dubbed "Darth Vader's lunchbox."

By 1985 CP/M machines had been roundly beaten by DOS-based PCs from IBM, Compaq, and others. Kaypro tried to jump on the IBM-compatible bandwagon with the Kaypro PC and Kaypro 286i models, but they were too little too late.

Enter IBM: The World Changes

It didn't take long for the world's largest manufacturer of mainframe and mini computers to recognize the potential of the burgeoning personal computer market. IBM started nosing around the market in the late 70s, and in 1980 approached Digital Research to license the CP/M operating system for what would eventually become known as the IBM Personal Computer. Digital Research didn't play ball, so IBM worked out a deal with Microsoft to supply the PC's operating system, in the form of PC DOS. Had IBM used CP/M instead, we may have been telling a different history today.

As it turned out, the IBM PC (released in 1981) was a hit, and the microcomputing world became a race between IBM and various companies selling IBM-compatible models – all running PC DOS or its generic variant, MS-DOS. Computers running CP/M became also rans.

Osborne was one of the first casualties of IBM's entry into the personal computer market – although, truth be told, competitor Kaypro had paved the ground for the company's demise. Osborne didn't release a successor to the Osborne 1 until 1985, two years after the company had filed for bankruptcy in 1983.

Kaypro lasted a little longer, thanks to its large consumer base. It hung on through the 1980s, selling non-descript IBM clones, but eventually faded into irrelevance. Kaypro initially filed for bankruptcy in 1990, restructured for a bit, and finally went out of business in 1992.

Today's computer users probably don't recognize the debt today's PCs owe to the Osborne 1 and Kaypro II. Those two ancient units defined the desktop PC as we know it today, and helped inspire IBM to enter the market. Without Adam Osborne or Andrew Kay, who knows how the market for personal computers would have developed.

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