How to Choose the Right Processor Architecture for IoT Devices: RISC-V, ARM and x86

Choosing the right processor architecture is crucial in the rapidly growing field of IoT (Internet of Things). This article compares the features and advantages of x86, RISC-V, and ARM processor architectures in IoT applications. The RISC-V architecture is exemplified by SiFive FE310 and FE310-G002 processors. The ARM architecture is represented by Cortex-M0+ and M3 processors. Intel processors are showcased through N100 and Atom x7000E series, aiding readers in selecting the best option for their devices.

RISC-V, ARM, and X86 Overview

Strengths and Challenges of RISC-V, ARM and x86 in IoT Applications

The choice of RISC-V, ARM or x86 architecture depends on their differences in performance, power consumption, cost, and ecosystem support. Here is a summary of the differences between RISC-V, ARM, and x86 architectures in these aspects.

RISC-V, ARM, and x86 chips for IoT Applications

Here are some examples of RISC-V, ARM, and x86 chips commonly used in IoT applications:

RISC-V: SiFive FE310

These RISC-V cores are designed for IoT and embedded applications, offering low power consumption and customizable features.

FE310 chip is SiFIVE first chip (and the first open-source chip) targeted at IoT devices.

The FE310 features SiFive's E31 CPU Coreplex, a 32-bit RV32IMAC core running at 320+ MHz. Additional features include a 16KB L1 Instruction Cache, a 16KB Data SRAM scratchpad, hardware multiply/divide, debug module, one-time programmable non-volatile memory (OTP), flexible clock generation with on-chip oscillators and PLLs, and a wide variety of peripherals including UARTs, QSPI, PWMs and timers. Multiple power domains and a low-power standby mode ensure a variety of applications can benefit from the FE310, which was fabricated in TSMC 180nm.

For details, please visit here.

RISC-V: SiFive FE310- G002

FE310-G002 is an upgraded version of FE310, which has undergone a series of improvements and upgrades based on the original FE310. It is still a 32-bit processor core based on the RISC-V architecture, specifically the RV32IMAC core, but it offers higher performance and more extensive features. For instance, FE310-G002 introduces a larger L1 instruction cache and data SRAM scratchpad, supports hardware multiply/divide, and adds more peripheral interfaces such as UART, I2C, QSPI, PWM, and timers. FE310-G002 aims to further enhance developers' capabilities in the development and deployment of IoT and embedded applications.

Key Features:

For details, please visit here.

Arm Cortex-M0+ and M3

The Arm Cortex-M0+ processor is an ultra-low power 32-bit processor designed for very low-cost IoT applications, such as simple wearable devices. The low price point is comparable with equivalent 8-bit devices, but with 32-bit performance. Microcontrollers built around the M0+ processor provides developers with excellent battery life (months to years), a rich peripheral set and a basic amount of connectivity and computational performance. The latter means that only simple algorithms can be implemented, such as algorithms for filtering accelerometer data before transmission.

Key Features:

• Armv6-M architecture.
• Bus interface AHB-lite, Von Neumann bus architecture.
• Thumb/Thumb-2 subset instruction support.
• 3-stages pipeline.
• Non-maskable interrupt + 1 to 32 physical interrupts.
• Wakeup interrupt controller.
• Hardware single-cycle (32x32) multiply

For more about MCortex-M0, please visit: https://developer.arm.com/Processors/Cortex-M0.

The Cortex-M3 is a step up from the M0+, offering better computational performance but with less power efficiency. The extra processing power, rich hardware peripheral set for connecting other sensors and connectivity options makes the M3 a very good choice for developers looking to develop slightly more advanced wearable products, such as the Fitbit device that is based on ST’s low-power STM32L series of microcontrollers.

Key Features:

Differences between the Cortex-M3 and -M0

The Cortex-M3 processor is based on the ARMv7-M architecture. It supports many more 32bit Thumb instructions and a number of extra system features.

The performance of the CortexM3 is also higher than that for the Cortex-M0. These factors make the Cortex-M3 very attractive to demanding applications in the automotive and industrial control areas.

For more about Cortex-M3, please visit here.

Intel N100 Processor

The Intel Processor N100 is a mobile processor with 4 cores, launched in January 2023, at an MSRP of $128. It is part of the Intel Processor lineup, using the Alder Lake-N architecture with BGA 1264. Processor N100 has 6 MB of L3 cache and operates at 100 MHz by default, but can boost up to 3.4 GHz, depending on the workload. Intel is building the Processor N100 on a 10 nm production process. The multiplier is locked on Processor N100, which limits its overclocking capabilities.

With a TDP of 6 W, the Processor N100 consumes extremely little energy. Intel's processor supports DDR4 and DDR5 memory with a single-channel interface. The highest officially supported memory speed is 4800 MT/s, but with overclocking (and the right memory modules) you can go even higher. For communication with other components in the system, Processor N100 uses a PCI-Express Gen 3 connection. This processor features the UHD Graphics 730 integrated graphics solution.

Key Features:

The Intel N100 processor is a low-power, high-performance processor specifically designed by Intel for IoT applications. It is based on the x86 architecture and features a compact size and low power consumption, making it suitable for embedded systems and IoT devices such as smart homes and smart cities.

For details, please visit here

Intel Atom® Processors x7000E Series and Intel® Core™ i3-N305 Processors for IoT Edge

Accelerate deep learning and media processing for IoT edge applications like digital signage, POS systems, and more with power-efficient Intel Atom® processors x7000E Series, Intel® Processor N Series, and Intel® Core™ i3-N305 processors. These processors feature the same Efficient-core (or E-core) and Intel® UHD Graphics driven by Xe architecture as 12th Gen Intel® Core™ processors. Using the same architecture makes it easier to port applications and solutions across Intel® CPU performance and power ranges.

Including up to four cores in Intel Atom® processors x7000E Series and up to eight cores on Intel® Core™ i3 processors, these processors offer LPDDR5 and DDR5 memory, and expanded I/Os. The processors deliver up to 1.30x faster single-thread performance and up to 1.09x faster multi-thread performance as compared to previous generation.They also offer critical capabilities for IoT edge use cases like hardware virtualization, multi-OS support, and real-time computing.

Key Features on the Intel Atom® Processors x7000E Series

Expand your IoT edge capabilities for AI, 4K media, and real-time computing with Intel Atom® processors x7000E Series (6W to 12W) and Intel® Core™ i3 processors (9W to 15W). They blend efficiency, performance, deep-learning inference accelerators, and built-in Intel® UHD graphics for edge applications, making them ideal for retail point of sale (POS) and digital signage devices, portable medical imaging devices, or office automation.

About more, please visit here.

Conclusion

In IoT applications, the x86, RISC-V, and ARM processor architectures each have unique characteristics and advantages. The x86 architecture is typically known for high performance and a mature ecosystem, making it suitable for IoT devices with demanding performance requirements. On the other hand, the ARM architecture excels in energy efficiency and power consumption, particularly well-suited for mobile and embedded devices. Meanwhile, RISC-V, with its open-source nature and flexibility, provides a new solution for customized and cost-sensitive IoT devices. When selecting a processor architecture, it is important to consider the device's performance needs, energy consumption requirements, and overall cost in order to provide more comprehensive solutions for the IoT field.