February 29 sees the launch of Microsoft's latest operating system (OS), Windows 8. One of the most significant developments thought to be vital to Microsoft's long term health, will be that the OS will run on ARM processors as well those from Intel and AMD.
ARM design chips outsell the better known Intel and AMD combined - 6.1 billion in 2010 - hence the importance of compatibility, but if you are running a Windows based computer those are the only two names you are probably familiar with but you almost certainly have at least one device powered by an ARM designed chip or containing one. What's even more surprising is that ARM do not make or even market microprocessors like AMD who outsource all their production.
All ARM do is design chips and license its technology for other companies, including Intel, to incorporate in their designs. The company earned $192 million in the third quarter of 2011, a 20%+ increase over the same period the previous year. You do not have to own a Windows PC - or any computer for you to hardly move without hitting something with "ARM Inside". Do you have a smartphone? The iPhone and 95% of all smartphones have ARM technology. Get into your car and the dashboard display, the anti-lock braking system, the airbag and your GPS could all include ARM technology.
ARM's success is built on its use of "Reduced Instruction Set Computing" or RISC. Very simply explained, this does away with the numerous instructions that processors like the Intel Pentium series employ in favor of a much smaller list. So instead of, for example, the processor using its internal functions how to perform a calculation like finding a square root, this is done by the software. The effect is a much faster processor using much less power and is why your smartphone can do things that previously you would have relied on a full sized computer to do. It's also why your iPad does not scorch your legs like some laptops do.
You are probably thinking this is one of those Californian Silicon Valley companies. Not so, it's from the "Silicon Fen" in Cambridge, England and its history is quite interesting. It's origins go back to 1980, the time Clive Sinclair had launched his ZX80 and ZX81 cheap computers - manufactured by Timex in Scotland and sold in the USA under their name. Another company, Acorn produced a rival home computer, the Atom, which had the advantage of a proper keyboard rather than the membrane used by Sinclair.
The BBC then decided that as part of its educational remit it should promote the learning of programming in schools and the general public through television teaching. To do this, it needed to reference a particular computer. Sinclair responded with a proposal that was to become the Spectrum, another very cheap computer with its membrane keyboard overlaid by rubber 'keys' to provide a more tactile response. Acorn's design, an advance on the Atom, was to become the BBC Micro. The success of both explains why the UK had the greatest market penetration of home microcomputers throughout the 1980s and still is one of the largest games producers. (One of the challenges in education in the UK today is moving back to teaching programming rather than the use of commercial software in IT courses). The BBC Micro still used the then available 'Complex Instruction Set' chips like those found in the Apple II. Although blocky, its graphics remain to today as they were the same as those adopted by the BBC for its 'Teletext' service that provides subtitling as well as information services like weather forecasts broadcast using the spare lines on analogue television. They will finally disappear as the analog TV service closes in Northern Ireland at the end of the year.
Following the success of the BBC Micro, Acorn developed a low cost version to rival the Sinclair Spectrum, the Electron and wanted to move into the business market. In developing their 'Business Machine' they found problems integrating multiple processors decided to move to the relatively new idea of RISC computing, launching the Acorn RISC Project in 1983.
Financial difficulties caused in part by component delays for the Electron and inflexible supply contracts but also to the commitment to the production of the BBC Master, the successor to the Micro, led to Acorn being taken over by Olivetti for a brief period. The Master was launched in 1986 and sold about 200,000 units mostly to schools and universities. Available for it was an additional ARM processor which was programmed from the Master, the first commercial use of their ARM architecture.
Their next development was the launch of the Archimedes, a desktop computer using ARM architecture together with an operating system that incorporated a "graphical user interface' about 3 years before Microsoft introduced theirs with Windows 3.
Acorn's chips were produced by a partner, VLSI, which was tasked with promoting the ARM processors. Apple became interested in using this in a prototype computer designed for educational use (they and Acorn dominated the UK educational computing market) and for what became their Newton PDA. The three companies formed a joint venture, ARM (Advanced RISC Machines) Ltd to develop Acorn's technology with Apple and Acorn having 43% of the company and VSLI the remainder.
While Apple and ARM were to survive the downturn in the mid 1990s, Acorn made some ill-judged moves into the television set top box market with too-early video on demand models. Eventually their holding in ARM was worth more than the company and it was sold off. Acorn itself disappeared as part of Broadcomm by 2000 and Apple's stake in ARM was under 15% by 1999.
Since then ARM Holdings have acquired a number of related business to become one of the largest companies in selling intellectual property to the microprocessor industry. Its latest 7th generation ARM designs promise the processing power of an Intel i5 while consuming the electrical power about a tenth of it, ideal for tomorrow's powerful mobile devices. Samsung's Exynos 4210SoC chip is intended to power smartphones, tablet computers and netbooks and in virtually a "computer on a chip" and has a dual core ARM Cortex-A9 processor at its heart. It will be in exactly the sorts of products that Windows 8 is intended to run on.
While desktop computers and full laptops may well continue using Intel and AMD, the Barcelona Computing Center is using ARM-based Nvidia Tigra processors to build a supercomputer 20 times more efficient than using conventional "x64" processors by 2014.