Sunday, May 21, 2023

Chips: The Story Of Arm

From the Chip Letter substack (byte-sized stories...), February 5:

The Arm Story Part 1 : From Acorns

How a new RISC architecture was developed at a small British company.


Hermann Hauser
A Personal Prologue

One dark and cold evening in the mid-1980s a young student walked through the ancient streets of Cambridge in the U.K. to a Victorian lecture theatre. Once in the building, he was joined by a couple of dozen other students to listen to a talk about a new piece of computer hardware.

The man giving the talk worked for Acorn Computers, makers of the BBC Microcomputer. His presentation was startling. Acorn needed a replacement for the ageing 8-bit 6502 microprocessor used in the BBC micro. They’d looked at new designs from US firms like Intel and Motorola, and they didn’t like them. So they’d designed their own.

That was surprising enough. It seemed bold for a company with no previous experience to design a microprocessor from scratch. What followed was even more remarkable. The chip Acorn had designed was 32-bit rather than 16-bit like the competitors. And not only was it faster, it also used a lot less power.

That student was me. The new microprocessor was the first Acorn RISC Machine, the first of a series of designs that we now know as Arm. There are many things about that evening where my memory has faded. I think the presenter was Steve Furber, but I can’t be certain. I don’t believe that there was a demonstration of the new system that evening. I do remember being surprised, impressed and somewhat sceptical about Acorn’s new microprocessor.

Fast-forward almost four decades, and we know how the story has played out. Arm processor designs are now used in hundreds of billions of devices around the world.

In this series of posts, I’m going to revisit the story of Arm, starting with its origins inside Acorn.

I was initially a little reluctant to write about the early years of Arm. There have been lots of excellent and extensive descriptions of the story (see the supplement to this post for lots and lots of links!), but in the end there were a few aspects of the story that I felt deserved more focus. I hope that, even if you’re familiar with the Arm story, then you’ll find some new points of interest.

Throughout this series of posts, we’ll be looking to answer one simple question. Why did this architecture from a small, ultimately failed, British company come to be so important and to survive and prosper against much larger competition?

Rather than comment on this as the story progresses, I’ll look to summarise the conclusions in a post at the end of the series.

If you’re enjoyed this then you might enjoy the supplement to this post which is available to paid subscribers and which has links to over eight hours of video and lots of other materials on the early days of the Acorn RISC Machine.

So let’s travel to the ancient university City of Cambridge in the UK in the late 1970s.

Cambridge Processor Unit
It all starts with Clive Sinclair: visionary, compulsive inventor of new gadgets, and variably successful businessman.

Sinclair started his career writing technical guides for electronics enthusiasts in the early 1960s. He soon started to market a variety of electronic products, moving through radios to calculators and then to digital watches.

In 1978 Sinclair, working with his longstanding employee Chris Curry, launched a computer kit, the MK14, based on the National Semiconductor SC/MP 8-bit microprocessor. When Sinclair was reluctant to develop the MK14 further, Curry teamed up with Hermann Hauser, a physics postgraduate at the University, who had also grown interested in the MK14.

Hauser had been born in Austria and had taken his first degree in Vienna before leaving to start his PhD at Cambridge. Hauser met Chris Curry, who shared his enthusiasm for microprocessors and convinced the Austrian to start a company with him to build products based on microprocessors.

The new company was originally called (somewhat prophetically) Cambridge Processor Unit Limited (or CPU Ltd). They also needed a trading name and wanted a name that would put them ahead of Apple in advertisements and in the telephone directory. Acorn seemed appropriate for a company that wanted to grow, so ‘Acorn Computers’ was born....


The Arm Story, Part 2

The Arm Story, Part 3

August 2020
Cambridge Tech Grandee Hermann Hauser Says Selling ARM to Nvidia Would Be a Disaster
Dr. Hauser is one of the poobahs of BritTech and was part of the team that spun ARM out of Acorn Computers in 1990....

September 2020
"Arm co-founder starts ‘Save Arm’ campaign to keep independence amid $40B Nvidia deal" (NVDA)

Dr. Hauser is also invested in this one:
British AI Startup Graphcore Raises $200 Million From BMW, Microsoft