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Chip Hall of Fame: Acorn Computers ARM1 Processor

Reading this on a smartphone? Then you’re using a direct descendant of this processor right now

2 min read
Photo of Acorn Computers ARM1 Processor

Acorn chip Photo: Acorn Computers

ARM1

Manufacturer: Acorn Computers

Category: Processors

Year: 1985

In the early 1980s, Acorn Computers was a small company with a big product. The firm, based in Cambridge, England, had sold over 1.5 million 8-bit BBC Micro desktop computers as part of the BBC’s national Computer Literacy Project. It was now time to design a new computer. Unsatisfied with the processors then available on the market, the Acorn engineers decided to make the leap to creating their own 32-bit microprocessor.

They called it the Acorn RISC Machine, or ARM. RISC, which stood for reduced-instruction-set computer, was an approach to designing processors that traded more complex machine code for higher efficiency. The engineers knew it wouldn’t be easy; in fact, they half expected they’d encounter an insurmountable design hurdle and have to scrap the whole project. “The team was so small that every design decision had to favor simplicity—or we’d never finish it!” says codesigner Steve Furber, now a computer engineering professor at the University of Manchester. In the end, the simplicity made all the difference. The ARM was small, low power, and easy to program. Sophie Wilson, who designed the instruction set, still remembers when they first tested the chip in a computer. “We did ‘PRINT PI’ at the prompt, and it gave the right answer,” she says. “We cracked open the bottles of champagne.” In 1990, Acorn spun off its ARM division, and the ARM architecture went on to become the dominant 32-bit processor for embedded application. More than 10 billion ARM cores have been used in all sorts of gadgetry, including one of Apple’s most humiliating flops, the Newton handheld, and one of its most glittering successes, the iPhone. Indeed, ARM chips are now found in more than 95 percent of the world’s smartphones.

Photo: Steve Furber/Acorn Computers

One of the earliest sketches of the ARM1’s architecture.

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Inventing the Atari 2600

The Atari Video Computer System gave game programmers room to be creative

18 min read
Brown and black gaming console with Atari logo labeled video computer system

The Atari Video Computer System (VCS), first released in 1977, was subsequently renamed the Atari 2600 and became the most popular home game machine of its era.

Evan Amos

In late 1975, sales of devices that made it possible for consumers to play Pong on home television sets were booming. At Atari Inc., which had first introduced Pong as an arcade game and had manufactured one of the most popular home versions of Pong, engineers began looking for the next arcade game to put in consumer hands, anticipating that people would grow tired of two paddles and a ball.

They saw Jet Fighter and Tank, but instead of designing a custom chip for each game, as was done for Pong, they planned a system that would play both games, four-player Pong if anyone was interested, and possibly a few other, as yet unknown games. The system was to be based on a microprocessor.

In a few months, Atari's designers in Grass Valley, Calif., had made a working prototype, and over the next year, designers from Grass Valley and from Sunnyvale, Calif., refined what was to be the Atari Video Computer System (VCS). It was released in 1977, and six years later ranks as one of the most successful microprocessor-based products ever built, with over 12 million sold at about $140 apiece.

Success did not come without problems. Production problems in the first two years caused Atari losses estimated near $25 million. But once these problems were solved and enough software was developed, the VCS took off.

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