Personal Mobile Tool Collection

Ending the Confusion: The Definitive Guide to Sharp's Japanese and International Zaurus Models

Comparison Chart, Facts and Fiction

Last update: 19 December 2003

Ulrich Plate

Rant and rave in guise of an introduction

I'm a Zaurus fan, no doubt about it. Like all followers of a cult, Zaurus fans get easily irritated when somebody badmouths those cherished gadgets, tarnishes their image or otherwise jeopardises their success. Now, what is the worst thing that could happen to the Zaurus? To be quite honest, Sharp's marketing drones, international business developers and other corporate suits may well be it.

They could have had everything going for them. Developers smart as the proverbial whips, technological concepts way ahead of their time, innovative to the point of wondering whether the idea descended upon them from a parallel universe or somewhere similarly remote. Plus an environment enormously receptive to new gadgets. We're talking bubble economy here, after all, plenty of surplus dough in everybody's pockets, enough spare time to fiddle around with handheld electronics. And this trend held true even after the bubble burst. People had definitely outgrown the old technologies: typewriters and paper notepads were a thing of the past, everybody was waiting for a sign from the gods that the future was happening inside those palmtop computing devices.

On the other hand, there's very little to be said in favour of product management and marketing. What do you expect? They lost buckets full of cash in the first international marketing wave, and retired the ZR series in question after barely two years. The same was to happen all over again this year: Despite all the admiration they received for the technology and the daring move towards Linux, they withdrew from the European markets after the SL-5500G didn't perform as well as they'd thought (which was hardly surprising since it was sold at about twice as much as the same model in the US). Meanwhile, they've revamped their website a few times and managed to delete practically all evidence of earlier models from it. If you want information about the MI-10, you will need to go to the Wayback machine, I'm afraid. And sort of the last touch-up to an already gloomy picture, they're even amnesiac now: How on earth did they end up with the name "Galileo" for a recent server product? That's how they baptised the planned Japanese version of their Newton clone in 1994, even the press remembers it, how could Sharp neglect this?

So here it is. A monument to the techies in Nara, the people behind all this beautiful equipment. A memento to all the gadget lovers out there. And a reminder to the people in charge of business that whenever you're messing with the Zaurus, you're messing with us.

Zaurus history revisited

When Sharp introduced their "Personal Mobile Tool" in the US two years ago, not many people were aware of the fact that this company had created and subsequently dominated the Japanese PDA market for more than a decade already. The first prototype of what would later become the "Zaurus", the PV-F1, was introduced in 1992, building on five years of experience that Sharp had gathered with their organizer series, starting with the 1987 model PA-7000, the first PDA in the Japanese market ever. When the first real Zaurus, the famous PI-3000 hit the ground running in early 1993, it was to become the kickoff of a sheer endless series of successors pouring forth from Sharp's Nara-based PDA factory, at the frantic pace of a six-month-release schedule that hasn't slowed down until today.

The Ancestry: PA Series

Rumour had it that the initial reason for starting this adventure was overcapacity at Sharp's LCD screen factory. Something needed to be done with those surplus displays,
The mother of all PDAs
PDA ancestor Sharp PA-7000
or so the reckoning goes, and they came up with the idea of marketing a slightly more versatile handheld device than previous endeavours.

None of this is true. Sharp came forward with a concept called Pi²T (Personal Information Intelligent Tool) in 1992, and continuously grew along that outline. The Zaurus miracle started with a magic wand: the stylus, flattened in its first and several later incarnations, so much so that people called it a carpenter's pen. The PA-7000, to be exact, was the breakthrough: everything before were just organisers with limited appeal. All of a sudden you could use your electronic calender/address book/multi-purpose device by tapping away at a touch screen. All Sharp PDAs that followed the PA-7000 were immediate economical successes. They received the same kind of attention and respect for their technological advance as the Newton would get later on. Although limited to the Japanese market, these merits were acknowledged by and large: the Zaurus was the first pen-based input personal digital assistant really stirring the masses.

After three years they had already passed the mark of one million units sold in Japan. The breakthrough had come about sometime around 1995 with the introduction of the new handwritten character recognition engine, a technology so grand that it boosted the Zaurii sales totally out of proportion.

Early Japanese Zauri: PI Series

My personal exposure to the Zaurus started in 1998 when I moved to Japan. Our group of management trainees studying Japanese together decided to get an electronic dictionary, and I was part of the delegation that got to choose the device from a mind-boggling range of models at the local gadgetry discounter. We opted for a PI-6500 for two reasons: It had an excellent built-in four-way-dictionary that looked much more mature than even the dedicated Wordtank dictionaries, and more importantly: It had handwritten character recognition that actually worked.

We drove a hard bargain, bought 39 units at around 30,000 JPY each and never looked back. Although the proprietary graphical user interface and all applications were in Japanese (and we were just about to make our first steps learning the language), using the GUI was quite intuitive, and some of us started trying the PIM functions and the MORE soft games, along with the dictionary that everybody came to love instantly. You see, there's one difficulty inherent to learning Japanese that's impossible to solve with a Canon Wordtank or any other electronic dictionary without handwritten input: If you read a newspaper and don't know a specific character, it's very hard to look it up via a stroke count index or the so-called radicals (indexed graphems), and since you don't know the character you can't pronounce it, either, so the lookup via reading doesn't get you anywhere, either. But it is very easy to just copy the character stroke by stroke into the input area of your Zaurus, and have the machine recognise it for you.

Sharp had developed these devices based on the PA model design, but with a faster CPU, the SC620615. It was still a home-bred processor, but unlike the PA models, it now came bundled with a Z80 co-processor, responsible for handling the handwritten input. The Z80 contributed much to the astonishingly smooth action in the PI models.

A Walk on the Wild Side: The ZR Handhelds

On the peak of the PI success at home Sharp decided to try their luck at marketing PDAs in overseas markets. They probably should have stayed out of it altogether... Bad timing, lack of aggressive marketing, outrageous pricing and a refusal to let third party developers cook up applications for the new platform led to an utter desaster on the US market that drove Sharp out of the PDA business outside of Japan for more than five years. Mind you, Palm, Inc. did exactly the opposite on all four accounts, and guess who's still market leader.

All this in spite of a technically flawless concept. By adding a keyboard to the stylus input method and changing the form factor to what looks like a miniaturised laptop PC, they were ended up with rather smart-looking devices. But the problem with the ZRs was simply that people were just about to get used to stylus input, even with an awkward method such as Graffiti.

Interestingly enough, the technology was not wasted. The Japanese MT series ("Browser Board") was based on the same concept as the short-lived ZR models, again much more influential and altogether successful, mainly because the Japanese devices became hugely popular as mobile phone accessories, for electronic mail and quick Internet access on the move.

The Real Thing: MI Revolution

New CPU, new operating system, redesigned process scheduling, memory management, and a comfortable new development environment for external application hackers: the MI series finally delivered on all the promises the earlier products had made. Programmers wishing to develop their own applications could do it easily with the Sharp Zaurus Application Builder (SZAB) software development kit, available free of charge if you happened to renew your trial license once in a blue moon. Sharp had asked a Kyoto-based company called AXE to develop a microkernel, XTAL, to run on top of the brand-new 32-bit RISC processor by Hitachi, the SH3 that is still at the core of present day MI models like the E21 or E25.

Right in the thick of it, the MI series got powered up in 1999. The legendary MI-EX1 (640 x 480 XVGA colour screen!) was the first of the so-called "icruise" models with

Zauridae: The Ultimate Sharp PDA Reference Chart

Series CPU Operating system Availability* Models Remarks
PA series Sharp ESR-H (SC61860) ? 1985 -1992 PA-100 First PDAs on the Japanese market, but everything before the PA-7000 (1987) were just bloated pocket calculators. A handful of lunatics may still be using the emulator that can run applications for the PA models on their Windows PCs...
PV (unique) ESR-L (SC62015) +
ESR-H co-processor
? 1992 PV-F1 ESR-H, the old pocket calculator chip, was included solely for downward IC-card compatibility. The actual workhorse was the ESR-L 16 bit CPU Sharp had developed.
PI series ESR-L (SC62015), Z80 co-processor Synergy 1993 - 1998 PI-3000/6500/7000/8000/ Hard times for developers: Sharp provided no clues whatsoever when it came to programming, hackers had to reverse-engineer and code applications in assembler. All available documentation and tools came from users, not from the manufacturer...
Expert Pads ARM 610 Newton OS 1.0 to 1.3 1993 - 1994 PI-7000/PI-7100 (overseas)
Galileo (Japan)
Sharp's Newton MessagePad clones. Galileo, the Japanese version, never made it past the planning phase...
ZR series ESR-L (SC62015)
Z80 co-processor
Synergy 1996 - 1998 ZR-3000/3500, ZR-5000/5700/5800 Much too expensive (between 400 and 600 USD), but rather well thought out: the ZR-5800 even had a backlit 320 x 240 screen. Very similar to Psion and HP Jornada, still has its small fan community, and some free software here and there. Never sold in Japan.
MI series Hitachi SH3 (30 to 120 MHz) Zaurus OS 1998 - 2001 MI-10/10DC/110M/106/106M/310
MI-P1/2/10, MI-C1, MI-EX1, MI-TR1, MI-J1
MI-E1/21/25DC, MI-L1
Technological quantum leaps, not only compared to the PI series, but to the entire international competition. MI-10 sported the first reflective colour TFT display ever, a screen that later ended up in Compaq Aero devices, too. Very large developer and fan community, loads of free software available.
MT series Hitachi SH3 (several generations, from 30 to 120 MHz) Zaurus OS 1998 - 2001 MT-200/200SA/300/300C The "Communication Pals" or "Browser Boards", basically MI technology with a keyboard on top.
SL series StrongARM, XScale (SA-1100, PXA-210/250/255 Linux (Lineo Embedix, OpenZaurus) since 2001 SL-5000D/5500/5500G/5600
SL-A300, SL-B500, SL-C-700/750/760/860
And now for something completely different... The SL series was launched outside of Japan to test the market for Linux PDAs, and only later made it back into the home market, too. The sexier models are only available Japan now (or via importers charging hefty primes on top). The decision to go with a new processor class was the reason for adopting Linux. Had Sharp continued with the Hitachi design CPUs, they might have sticked to an enhanced Zaurus OS, but since it was to be modern post-ARM processors, they went for the first operating system since Newton OS to be a non-Sharp invention.
* End dates do not mean they went out of production that year, but refer to the introduction dates of the last model in the series.

Important links (last verified to be unbroken on 19 December 2003)

Japanese sources: