The birth of a giant tech UK

23 November 2010, Last updated at 12: 43 GMT Acorn made iconic BBC Micro that many gave their first taste of computing

British chip Designer ARM will soon twenty years. Bill Thompson was there at the beginning.

During the eighties, I worked for Acorn Computers in Cambridge, helping to develop systems for in-house engineering that were used by designers to create computer like Archimedes, the successor to the BBC Microcomputer that had made the Acorn name during the BBC computer literacy project.

The computer on my desk was a BBC Micro model "B" with a whopping 32 kilobytes of memory and, I believe, a 10-megabyte hard disk.

When I had to write a program to calculate hours worked for my team that I don't use the language BASIC shipped with every BBC Computer, but wrote instead using PostScript, the special programming language used to establish the documents on the Apple LaserWriter printer very expensive that we had our plan and got the printer to make computations I needed.

This printer not only had a surprising and half megabytes of memory-necessary to deal with large files-but used a Motorola 68000 processor, making it much more powerful ageing 6502 in my desktop, so it was much faster.

However, there was much excitement in the Office on a different processor type, one that was developed by the research and development team within Acorn: the Acorn RISC Machine, or the arm.

ARM chips were just starting to appear, and like everyone else in Acorn spent much of my time working, the beautiful game "Lander" which was written to display their graphics capability and speed.

"RISC" means "Reduced Instruction Set Computer" and describes an architectural approach that reduces the complexity of fundamental logical operations which the processor is in favour of the rapid execution of a small set of basic tasks and the ARM chip marked a radical break with the dominant processor designs.

RISC chips have fewer transistors and simpler architectures, but they can be programmed to run very efficiently. They also use much less energy than conventional processors, which makes them ideal for use in systems that have limited the power should not be heated, such as mobile phones.

This explains why ARM chips are now on mobile phones and mobile devices from Nokia, Samsung, Sony Ericsson and, of course, Apple.

Mobile power

Although the arm started within Acorn, it does not stay there.

In November 1990 Acorn created a joint venture with Apple and VLSI chip manufacturer and Advanced RISC Machines Ltd was established to develop the ARM architecture. Since then it has become the most successful British company emerged from Silicon Fen, with offices worldwide, and chips in billions of devices.

The secret of the success of the boom is that it actually doesn't make a lot of processors. Instead, it licenses its designs to other companies who then embed a "core ARM" in their more complex processors, which manufacture then themselves.

ARM-processors are designed in about 80% of all mobile phones

Their designs are now divided into three groups, or profiles. Application for general processing, real-time and microcontrollers, embedded systems found in many machines.

Who wants to play with an ARM processor can get your hands on one very easily by mbed, a research project that provides an arm ARM Cortex microcontroller over a 40-PIN with a USB interface and a variety of tools for web-based support that allow you to write and compile programs in c and c++.

As the open source Arduino platform, it is designed to encourage exploration, learning and prototyping, with a large and growing web-based user who share ideas and code.

And next week engineers mbed are celebrating the 20th anniversary of the arm so appropriately geeky by running a robot racing competition using an mbed controlled robot that can be driven using an Android tablet.

In the 1990s, most of us took that Acorn's main impact would prove to be the generation of people that sat down in front of the boot screen of a BBC Micro and grappled with a command line to type your own programs in BASIC.

But 20 years later the billions of ARM processor cores in smartphones and PDAs everywhere that characterize our world.

ARM has become one of the most important businesses of propulsion us in the electronic age and showed considerable skill in navigating in the new environment that helped to create. I can't wait to see what it has done since its 40th anniversary.

Bill Thompson is an independent journalist and regular commentator on the BBC World Service Digital Planet. Is currently working with the BBC on its draft archive.