Written by Elena Petrova | 11/19/2023

ARM

ARM, originally Acorn RISC Machine, now Advanced RISC Machines, is a family of reduced instruction set computing (RISC) architectures for computer processors, configured for various environments. ARM Holdings develops the architecture and licenses it to other companies, who design their own products that implement one of those architectures⁠—including systems-on-chips (SoC) and systems-on-modules (SoM) that incorporate memory, interfaces, radios, etc., as well as complete computers in a single chip.

ARM Architecture Fundamentals

  • RISC Philosophy: ARM is based on the RISC (Reduced Instruction Set Computing) architecture, which simplifies the processor design by using simpler instructions that can execute within a single clock cycle. This efficiency allows for lower power consumption and smaller chip sizes, making ARM ideal for portable devices.

  • Licensing Model: ARM Holdings does not manufacture CPUs but rather licenses the architecture to other companies. Licensees can design their own processors that implement the ARM instruction set, allowing for a wide variety of ARM-based processors tailored to different markets.

  • Efficiency and Performance: ARM processors are known for their exceptional energy efficiency, which has made them the architecture of choice for mobile phones, tablets, and other battery-powered devices where power consumption is a critical concern.

ARM in the Market

  • Mobile Devices: ARM is the dominant architecture used in smartphones and tablets. The majority of mobile devices run on SoCs based on ARM designs due to their low power consumption and high efficiency.

  • Embedded Systems: Because of its power efficiency and small size, ARM is widely used in embedded systems, including automotive systems, industrial controllers, and IoT devices.

  • Servers: ARM-based servers are becoming more popular, especially in environments where power efficiency is critical, such as data centers.

  • Personal Computing: With the introduction of ARM-based laptops and desktops, ARM is expanding its reach in the personal computing space. Operating systems like Windows on ARM and Apple's transition to their own ARM-based M1 chips for Macs are significant indicators of this trend.

Technical Characteristics

  • Cores: ARM cores come in a variety of configurations, from the simpler, lower-power cores like the Cortex-A53 to the more powerful designs like the Cortex-A77.

  • 64-bit Processing: Modern ARM designs support 64-bit processing, which allows devices to handle more memory and larger data sets, improving performance for demanding tasks like high-resolution video playback and complex computations.

  • Customizability: Companies can customize their ARM processors to integrate various features like graphics processing units (GPUs), image processors, AI accelerators, and more, all within the same chip.

ARM and Software Development

  • Cross-Platform: Software development for ARM processors can be done using standard programming languages, but it often requires cross-compilation, where the software is compiled on a different architecture and then transferred to the ARM-based system.

  • Ecosystem: There is a rich ecosystem of development tools, software libraries, and operating systems that support ARM, including Linux distributions, Android, and, more recently, full versions of Windows 10.

The Future of ARM

  • Innovation: ARM continues to innovate, with new designs that improve upon energy efficiency and performance. They are also pushing into new markets with designs for server processors and edge computing devices.

  • Acquisitions and Partnerships: ARM Holdings has been the subject of significant industry attention, with NVIDIA expressing intent to acquire the company as of my last update in April 2023, although this has faced regulatory scrutiny.

In summary, ARM architecture represents a paradigm shift towards efficiency and customizability in the processor market. Its wide adoption in mobile and embedded systems, and the growing presence in traditional computing, underline its importance in the current and future landscape of technology.