The Symbian OS (779886), страница 6
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Volumes have continued to rise steadily sincethen, and Symbian OS passed the 100 million phones shipped milestonein Q4 2006. Those numbers translate into close to 70% of the high-end,or smartphone, market according to independent sources.3At the same time, competition has probably never been greater.In 2006, Linux phones are shipping in substantial numbers in Japanand China. Microsoft launched the latest version of its mobile phoneplatform, Windows Mobile 5, in late 2005 and phones based on it arenow shipping.4 Qualcomm has signed up European networks for the firsttime to support its (previously CDMA-only) Brew platform.
And while thefuture of the Java-based SavaJe platform is uncertain, ‘all-Java’ phonesremain a possibility.5But, at the time of writing, the biggest volume of phones (i.e. acrossthe whole market) are based on none of these platforms at all and remainthe mid- to low-end phones based on vendors’ own proprietary operatingsystems. In 2006, Symbian set its sights on addressing this market and its3In fact, Canalys puts Symbian’s market share at nearer 80% based on data for Q3 2006(see www.canalys.com/pr/2006/r2006102.htm).4Windows Mobile 5.0 is based on WinCE 5.1.5To split hairs a little, SavaJe is not in fact ‘all Java’: the kernel and low-level system iswritten in C and the system layers are a mix of C/C++ and Java.IN THE BEGINNING17v9 releases will increasingly be aimed at scaling not just for the high end,where it is a proven platform for the latest feature-laden phones, but forthe mid-range, mass-volume consumer market.2.2 In the BeginningIn the summer of 1994, Psion was a company of perhaps 40 softwareengineers and as many hardware engineers, with a product line ofhandheld organizers that was highly profitable.
The most recent was thePsion Series 3a, the second in the Series 3 family, a pocket-sized phonewith a clamshell design sporting a letterbox format grayscale displayhinged over a QWERTY keyboard, with an x86-family processor inside,up to 2 MB of RAM, removable flash memory cards and a ROM-based16-bit operating system (named SIBO) for an all solid-state design. Itshardware design was not revolutionary but it was striking. Even more sowas its built-in set of easy-to-use productivity applications. Supported bya dedicated, BASIC-like programming language called OPL, a thrivinghobbyist community had established itself, self-organized (in pre-WorldWide Web style; the first release of the Netscape browser appeared thatsame year) around bulletin boards and news groups and writing add-onsoftware.OPL was in fact a carry-over from Psion’s original Organiser productline, which was also doing nicely, having been enthusiastically adoptedas a stock control tool by UK high-street retailers such as Marks & Spencer.That particular summer, the big project was a true Visual Basic clone(called OVAL) for the Series 3a, intended not just to increase the capabilities of the machine, but to open a bridge to the programming mainstreamand tap the rich potential of the hobbyist programming market in BASICfor DOS and the Macintosh.At the same time a much smaller project was also kicked off to createa next-generation operating system for the 32-bit devices which thecompany was already planning as replacements for the 16-bit Series 3range as part of its strategy for retaining its lead in the handheld market.(In 1994, Palm had yet to release the Pilot; indeed it was still a softwarehouse, writing connectivity software for Psion’s Series 3, among otherthings.
Apple’s Newton was a year old and genuinely innovative buthad failed to find much of a market. Microsoft had not yet releasedWindows CE and the Hewlett Packard machines which were the nearestcompetitors to the Series 3 were based on MS-DOS and primitive incomparison.6 )6In 1991, Hewlett Packard introduced the HP-95LX palmtop running MS-DOS andapplications such as Lotus 1-2-3, with a 16x40 text display.
It was improved to an 80x25display on the HP-100LX in 1993 and upgraded again with the HP-200LX in 1994. Devicesbased on Windows CE, starting with the HP-300LX, did not appear until 1997.18THE HISTORY AND PREHISTORY OF SYMBIAN OSThe follow-on to the Series 3 was codenamed Protea,7 and over thenext year the project continued to grow. By the end of 1995 it wasdriving a rapid expansion of the company and in particular the projectto create the new operating system (which was eventually named EPOC)was consuming the lion’s share of the company’s software developmentbudget, although the Series 3 software remained in active development.For example, email and Internet extensions, in particular, were beingprepared as it became increasingly clear that accessing Internet servicesfrom handheld devices was likely to become a significant market driver.The Protea story has been told before [Tasker 2000, p.
14]. The briefwas simple enough – create the next-generation successor to the Series3, a more sophisticated 32-bit handheld to be called the Psion Series 5.8In this sense, then, the project was quite narrowly focused on creatingthe next successful product.
But from the software perspective, the longerterm vision for EPOC was explicit. The design brief called for it to supportnot just the explicit requirements for Protea applications, but the as-yetunidentified requirements for other future products. While there was asyet no talk of licensing the operating system, there was a long-term vision.The next generation, like the current generation, would be a family ofproducts and there was an explicit intention that the software should aimfor a design life of perhaps ten to fifteen years.The Protea project delivered in the early summer of 1997.
Like manycomplex software projects, it was late but not excessively so. However,somewhere along the way an interesting shift had occurred. By the timethe all-new Psion Series 5 shipped in June 1997, the software side of thecompany had been spun out (as Psion Software, in late 1996) and the firstlicensee software projects had started.The Series 5 was an outstanding industrial design, with a true tactilekeyboard (on which you really could touch type) and a backlit touchscreen with an ingenious hinge that ensured the device remained stablewhen used with a pen in touchscreen mode.9 (Competing, non-Psionproducts tended to fall over backwards when the screen was pressed.) ACF card slot was provided for expandability and, best of all, the Series 5seemed to run forever on two AA batteries.
As for the software, it rapidlyacquired a reputation for extreme usability and legendary robustness(after some natural early teething troubles).The Series 5 was a best-seller though, quite probably, it did not sellas well as its predecessor, the Series 3. (In its lifetime of five years of7Protea is the name of a flower native to South Africa. As it happens, Psion founder,David Potter, and the first two CEOs of Symbian, Colly Myers and David Levin, all share aconnection with Southern Africa.8Actually, as David Wood recalls, for a long time it was assumed it would be called theSeries 4.9Credit for the Series 5’s famous hinging clamshell case goes to Martin Riddiford of theTherefore design consultancy.IN THE BEGINNINGFigure 2.119The Psion Series 5 MXproduction, the Series 3 is thought to have sold more than 1.5 millionunits.10 The Series 5 and its immediate successors including the Revo,had a lifetime of four years of production, during which it sold probablyaround a million units (see Figure 2.1).The EPOC team had started with a clean slate, but the operating systemdid not come out of nowhere.
Many of the ideas had been tried, tuned andproven in one or more, sometimes all, of the previous systems. Clean and‘from the ground up’ it may have been but it was nonetheless a from-theground-up rewrite of the 16-bit operating system for the Series 3, whichin turn was a from-the-ground-up rewrite of the second-generation 8-bitoperating system for the Organiser II. (The first-generation 8-bit systemfor the Organiser I had only rudimentary operating system features andwas, in effect, written straight to the metal.)While, by any measure, the new operating system was written remarkably quickly,11 the fact remains that operating systems gestate slowlyand cost years of effort to create.12 Counting from the first Organisersystems, Psion had already invested a dozen years in operating systemdevelopment when the Protea project began.
Planning for a design life ofat least as many years for the new operating system was a matter of basiccommercial common sense.It is likely that, had Psion had been a pure software company (orjust a larger and more mature company), a from-the-ground-up rewrite,10See http://3lib.ukonline.co.uk/historyofpsion.htm.Martin Tasker puts its development time at 3.5 years and its cost at £6 million [Tasker2000, p. 15].12There have been some interesting attempts to quantify the development cost ofLinux (see for example the article by David Wheeler at www.dwheeler.com/sloc/redhat71v1/redhat71sloc.html).1120THE HISTORY AND PREHISTORY OF SYMBIAN OSlet alone one using a new and unfamiliar, object-oriented language,would not even have been considered, let alone allowed to complete.The business logic would almost certainly have favored extending theexisting system and Psion very likely would have missed its moment.
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