The History and Evolution of ARM: From Acorn’s Early Microcontrollers to Global Processor Dominance

In 1978 a company called CPU (Cambridge Processor Unit) was founded in Cambridge, UK, by physicist Hermann Hauser and engineer Chris Curry. Their first product was a microcontroller for a gambling machine, known as Acorn System 1.

In 1979 the company renamed itself Acorn Computer Ltd and released a series of systems (System 1‑4) and the consumer‑oriented Acorn Atom. The BBC’s 1981 educational computer project prompted Acorn to seek a suitable processor, leading them to develop their own RISC‑based chip after Intel refused to supply an 80286.

Computer scientists Sophie Wilson and Steve Furber at Cambridge designed the Acorn RISC Machine, later abbreviated to ARM, introducing the Reduced Instruction Set Computer (RISC) concept that emphasized a small set of frequently used instructions.

ARM’s early chips (ARM1, ARM2, ARM3) were used in the BBC Micro, and in 1990 Acorn spun out the ARM company (Advanced RISC Machines). ARM adopted an IP‑licensing business model, offering processor, POP (Processor Optimization Pack), and architecture licenses to partners.

Through the 1990s ARM licensed its designs to companies such as GEC Plessey, Cirrus Logic, Texas Instruments, Samsung, and Sharp. The ARM6 powered Apple’s Newton PDA, and the ARM7 enabled Nokia’s 6110, the first GSM phone with an ARM processor.

ARM’s low‑power, low‑cost approach made it ideal for mobile devices; by the late 2000s it powered Apple’s iPhone, Google’s Android, and countless smartphones, reaching shipments of over ten billion chips per year.

In 2016 SoftBank acquired ARM, keeping its licensing strategy intact. Today ARM’s product families include Cortex‑A (applications), Cortex‑R (real‑time), Cortex‑M (microcontrollers), and the security‑focused Cortex‑SC series, supporting a vast ecosystem of over 1,200 partners.

The success of ARM illustrates how a lightweight, open licensing model can outpace traditional vertically integrated semiconductor companies, especially in the era of ubiquitous low‑power devices.