The RISC-V Architecture: 16 Boards and MCUs You Should Know

Microcontrollers are everywhere, powering everything from your dishwasher to powerful computing systems and millions of wearable and IoT devices. For the processor cores and architectures, names such as ARM, AVR, MIPS, Xtensa, 8051, etc., dominate the landscape, each with unique strengths and areas of application. These platforms, used in many very popular microcontrollers such as the STM32, ESP32-S3, ATmega and so on, share a common trait: They are proprietary. Enter RISC-V, a relatively new player in the world of microcontrollers and processors.

Some of our readers may recall that we published a few articles on this topic a few years ago, when hardware choices were much more limited. Developed at the University of California, Berkeley, starting in 2010, RISC-V was envisioned as a forward-looking architecture unburdened by legacy compatibility. Unlike traditional processor architectures, RISC-V is open-source, modular, and designed in a modern way. More precisely, it is an open-standard instruction set architecture (ISA), i.e. a standardized definition of the instructions a processor can execute. It is designed to overcome the proprietary restrictions of traditional ISAs, such as those from Intel, AMD or ARM. Unlike proprietary ISAs, RISC-V allows anyone to implement its specifications without legal restrictions, fostering innovation and collaboration between companies and leading experts.

With an open ISA, many companies can develop and sell ready-to-use RISC-V cores, in the form of intellectual property (IP) blocks. A microcontroller manufacturer can buy a RISC-V core and use it in a microcontroller, adding the manufacturer’s own peripherals. This encourages competition between IP providers, stimulating innovation and driving down costs. Manufacturers can switch to higher-performance ICs without being locked into proprietary ecosystems.

RISC-V: A Simple Concept

RISC-V, as its name implies, adheres to the Reduced Instruction Set Computer (RISC) principles, which emphasize a small, optimized set of instructions. This reduces the complexity of hardware design and facilitates faster development cycles. Unlike legacy architectures such as x86, which carry decades of backward-compatibility baggage, RISC-V starts with a clean slate, incorporating only what’s necessary for modern applications. For example, RISC-V’s base consists of just 47 instructions, compared to hundreds on the x86. You can find details about the instruction set here, summarized by GitHub user msyksphinz-self. This lean design makes it easier to implement and verify, resulting in lower costs and fewer bugs. While this base instruction set is indeed quite minimalist, there are optional extensions that can be added as needed.

Modularity

The extensions enable processors to be customized to specific needs. There are about 30 of them, including multiplication and division (M) for arithmetic operations, atomic instructions (A) for multi-threaded programming, single and double-precision floating-point (F and D) for scientific computing and signal processing, vector processing (V) for parallel data operations, compressed instructions (C), etc. The full list can be found here along with more detail. This modularity optimizes silicon utilization and energy efficiency: Chip manufacturers can produce microcontrollers that contain just what is needed for a given application, without wasting resources, thus reducing costs. For instance, a microcontroller for IoT devices might exclude floating-point units to save power and silicon, while a processor for AI workloads would include vector extensions for accelerated computation. As an example, a nice diagram showing the base integer instruction set for a 32-bit core (RV32I) together with the M, A, and C extensions has been put together by Github user kuashio.

RISC-V: More Security?

RISC-V’s openness has spurred innovation in processor security. If you have an application for which security is important, then the open-source nature of RISC-V is a great feature: It’s then easier to inspect. It’s for the same reason that many crypto wallets are open-source! Extensions such as CHERI (Capability Hardware Enhanced RISC Instructions) enable fine-grained memory protection, reducing vulnerabilities to attacks such as buffer overflows. Unlike proprietary architectures, RISC-V allows researchers to experiment and implement security features without licensing restrictions.

Reducing Costs and Sharing Results

An open ISA eliminates licensing fees associated with proprietary ISAs. Microcontroller manufacturers can develop their own RISC-V cores or purchase ready-to-use intellectual property (IP) blocks from vendors. This competitive ecosystem drives down costs, making advanced microcontrollers and processors accessible to a wider audience. Further cost reduction is achieved by sharing the development of software ecosystems (compilers, OS support, etc.) between several companies. RISC-V’s open model encourages the pooling of resources and expertise, akin to how Linux revolutionized operating systems or Ethernet transformed networking. Companies can focus on unique differentiators rather than duplicating foundational work, accelerating innovation and improving the overall ecosystem.

Legal Peace of Mind for Everyone

For a university, how can you legally teach processor design to computer engineering students when x86 and ARM cores are not open-source? Beyond the legal constraints, there is also a technical challenge: These are not modular, which requires students to implement a massive set of instructions before achieving a potentially functional processor. Semiconductor multinationals also value this legal piece of mind. Have you heard about the legal dispute between ARM and Qualcomm? RISC-V, on the other hand, offers companies a different approach, with no licensing fees.

RISC-V Adoption by Major Players

RISC-V’s open approach has garnered significant attention, with major companies integrating it into their products. By 2015, the RISC-V Foundation was formed, attracting major players such as Google, NVIDIA, Western Digital, and NXP. Over the years, AMD, Qualcomm, IBM, and others have joined, further solidifying its presence in the market. NVIDIA uses RISC-V for specific cores in its GPUs, while Western Digital leverages it for storage devices. SiFive, a pioneer in RISC-V development, offers a range of processors for embedded and high-performance applications. The main IP suppliers are Nuclei, SiFive, and T-Head, while some manufacturers, such as Espressif and WCH, are developing their own IPs to differentiate their products. Without knowing it, you may already have used RISC-V hardware, such as the ESP32-C3, ESP32-C6, and ESP32-P4. Even Raspberry Pi incorporated RISC-V cores into its latest microcontroller, the RP2350, used on the Raspberry Pi Pico 2.

RISC-V in Practice

Despite the hype surrounding it, is RISC-V truly “revolutionary” for the average user? Most engineers and hobbyists program in C/C++ or other high-level languages, meaning you won’t need to learn this reduced instruction set. For developers and engineers, transitioning to RISC-V only requires modest changes to established workflows and habits. Tools such as compilers and development environments are already available and getting better every day. If you’re interested in embedded development, using RISC-V microcontrollers is a very relevant skill to acquire and add to your toolbox. For those who enjoy getting hands-on and programming in assembly, one of our authors has published a short article on our website about programming the RISC-V core on an ESP32-C3, with a companion Elektor book. For those who prefer programming in C on ultra-low-cost microcontrollers such as the CH32V003 from WCH, we’ve discovered an excellent educational site created by Vincent Defert. The site is in French, but we encourage you to use a browser extension for real-time translation to take full advantage of this outstanding content! Our bet is that the RISC-V standard is here to stay, and these skills will be easily reusable in the future. In the second part of this article, we will present some of the exciting RISC-V-based development boards available today that you can use for your next project. Have fun!

Notable RISC-V Development Boards

RISC-V development boards have been gaining traction in recent years as the RISC-V ecosystem continues to expand. These boards cater to hobbyists, researchers, and professionals looking to leverage the flexibility and open-source nature of the RISC-V architecture. Below is a detailed look at some of the most notable RISC-V development boards available today, their uses, and potential advantages.

HiFive Premier P550

The HiFive Premier P550 is a high-performance development board designed to push the boundaries of RISC-V development. Powered by the Eswin EIC7700X SoC with a quad-core SiFive P550 CPU, it provides a robust platform for developing and optimizing RISC-V operating systems and applications across diverse markets. It starts at $399 for the 16 GB RAM variant, and can support up to 32 GB of LPDDR5-6400 memory, 128 GB of eMMC storage, and HDMI 2.0 display support, enabling intensive computational tasks. Pre-installed with Ubuntu Linux 24.04, this board is perfect for advanced development in AI, operating system design, and high-performance application.

HiFive1 Rev B

The HiFive1 Rev B is an entry-level board designed for IoT and edge computing, powered by the FE310-G002 processor, which includes a 32-bit RV32IMAC core. Costing around $65, its 16 KB L1 instruction cache, 16 KB data SRAM, and support for flexible clock generation make it efficient for lightweight applications. With a USB debugger upgraded to SEGGER J-Link-OB and compatibility with SiFive Freedom Studio, developers benefit from seamless drag-and-drop flash programming and robust debugging tools. This board is ideal for prototyping IoT devices, developing low-power applications, and exploring the fundamentals of RISC-V development.

VisionFive 2 SBC

The VisionFive 2 is the world’s first high-performance RISC-V SBC with an integrated GPU, powered by the StarFive JH7110 SoC. With a quad-core CPU running up to 1.5 GHz and support for up to 8 GB LPDDR4 memory, it excels in multimedia processing and dual-display output via HDMI and MIPI DSI interfaces. Features such as three USB 3.0 ports, Gigabit Ethernet with PoE, and GPIO headers make it a strong contender for IoT, lightweight servers, and edge computing. Its robust multimedia capabilities, including 4K video decoding and encoding, make it ideal for developers exploring high-performance RISC-V applications in cost-effective projects, which is currently sold on Amazon’s website for $99.

MangoPi MQ-Pro SBC

Compact and efficient, this board serves as a viable alternative to the Raspberry Pi Zero, tailored for IoT and lightweight embedded systems. Equipped with the D1 RISC-V core, it supports Tina-Linux/Debian and runs complete Python applications. Its peripheral-rich design includes GPIO, I²C, SPI, and HDMI, making it ideal for small-scale automation, portable gadgets, and educational projects requiring minimal space and power. Its community-driven ecosystem ensures flexibility and ease of use in diverse lightweight applications. Surprisingly, you can get all these features for as low as $35.

Nuclei DDR200T Development Board

This board by Nuclei System integrates a Xilinx XC7A200T-2 FPGA for hardware acceleration, prototyping, and custom logic development, along with abundant storage and extended interfaces for versatile connectivity. The RISC-V microcontroller, the GD32VF103, enhances programmability, making it ideal for control tasks and interfacing with the FPGA. Its combination of FPGA flexibility and MCU integration supports industrial automation and embedded development. While priced at $770, the board justifies its cost with its advanced features and exceptional performance for demanding applications.

BeagleV Ahead

The BeagleV Ahead is an open-source RISC-V SBC powered by the T-Head TH1520 SoC, featuring a 2 GHz quad-core XuanTie C910 processor with advanced GPU and NPU capabilities. Its compatibility with BeagleBone Black cape headers allows for hardware expansion, making it suitable for robotics, AI, and multimedia applications. With support for Linux and open-source frameworks, it is designed to enable developers to explore the potential of RISC-V architecture in complex AI and machine learning projects. For only $150, this SBC punches well above its weight.

Milk-V Mars

The Milk-V Mars is a compact and high-performance RISC-V SBC powered by the StarFive JH7110 SoC, featuring a quad-core CPU clocked up to 1.5 GHz. It supports up to 8 GB of LPDDR4 memory, an eMMC slot, and SPI flash for bootloader storage, making it highly adaptable for development tasks. With three USB 3.0 ports, one USB 2.0 port, and an HDMI 2.0 output supporting 4K resolution, it is well-suited for multimedia projects, lightweight servers, and general-purpose Linux development. Additional features such as a 40-pin GPIO, PoE-enabled Ethernet, and MIPI interfaces for cameras further enhance its versatility, enabling use in IoT, edge computing, and embedded systems. At around $70 for the 8 GB variant, it’s a steal for the performance it delivers.

Milk-V Megrez

The Milk-V Megrez is a Mini-ITX RISC-V device powered by the Eswin EIC7700X SoC, featuring a quad-core SiFive P550 CPU at 1.8 GHz. Its built-in GPU supports advanced graphics standards such as OpenGL ES 3.2 and Vulkan 1.2, while the 19.95 TOPS NPU enables local AI processing for applications in machine learning and robotics. With support for up to 32 GB LPDDR5 memory, multiple storage options, including SATA SSDs and eMMC, and a range of connectivity options like HDMI, USB 3.0 and dual Gigabit Ethernet, this board is ideal for AI development, high-performance computing, and multimedia tasks. Its compatibility with Linux and versatile hardware interfaces make it a significant step forward in RISC-V desktop computing. You can grab this powerful board for $200.

Milk-V Duo 256M

The compact Milk-V Duo 256M is a versatile embedded development platform powered by the SOPHGO SG2002 chip. With a memory boost to 256-MB DRAM, it caters to applications requiring larger memory capacities. The platform features a dual-core RISC-V CPU (C906 at 1 GHz and 700 MHz) alongside a Cortex-A53 Arm CPU, enabling seamless switching between RISC-V and Arm architectures. Its TPU delivers 1.0 TOPS of AI computing power, making it ideal for edge intelligence in smart cameras, visual doorbells, and IoT devices. Rich GPIO interfaces (SPI, UART) and multimedia capabilities like H.265 video encoding, HDR, and noise reduction further enhance its suitability for industrial and smart home applications. The Duo also supports Linux and RTOS, offering developers a powerful and flexible platform for diverse projects. The boards are available for about €30.

Banana Pi BPI-F3

The Banana Pi BPI-F3 is an industrial-grade RISC-V development board powered by the SpaceMiT K1 8-core RISC-V processor, which integrates 2.0 TOPS of AI computing power. It offers flexible configurations with 2/4/8/16 GB DDR and up to 128 GB eMMC storage. With dual Gigabit Ethernet ports, four USB 3.0 ports, PCIe for M.2 expansion, and support for HDMI and dual MIPI-CSI cameras, this board excels in advanced prototyping, industrial applications, and AI-driven tasks. Its compatibility with Linux distributions and diverse hardware interfaces makes it ideal for high-performance computing and robust development environments. Available at $70, it strikes a perfect balance between cost and capability.

Espressif ESP32 boards

Espressif’s RISC-V-based MCUs, including the ESP32-P4, ESP32-C3, and ESP32-C6, are among our favorites and highly favored by the community for their versatility and robust software ecosystem. The latest and greatest ESP32-P4 features a dual-core CPU running at up to 400 MHz, an auxiliary low-power core, and 768 KB of on-chip SRAM with external PSRAM support. It excels in AI, IoT, and HMI applications, boasting 55 programmable GPIOs and extensive peripheral support, including USB OTG 2.0 HS, Ethernet, and MIPI-CSI for high-resolution cameras. With hardware accelerators and media encoding for H.264 at 1080p, it is a top choice for multimedia-rich projects. The wider Espressif RISC-V family offers excellent framework compatibility, making firmware development seamless across multiple platforms. These boards are also budget-friendly, with prices ranging from as low as $3 to $50, depending on the variant and features. One of the best options is the Seeed Studio XIAO ESP32C3, equipped with the ESP32-C3 SoC, combining 400-KB SRAM and 4-MB Flash in a compact thumb-sized design. It is ideal for the IoT, wearables, and low-power networking.

Bouffalo Lab BL616/BL618 and Sipeed M0S

The Bouffalo Lab BL616 and BL618 are 32-bit RISC-V wireless MCUs built for IoT applications. They support Wi-Fi 6, Bluetooth 5.2, and Zigbee, making them ideal for smart home devices and Matter-based automation. Running at up to 320 MHz with an integrated FPU and DSP, they balance performance and efficiency. With 480 KB SRAM, embedded flash, and multiple communication interfaces (USB 2.0, SDIO, SPI, I²S), they are versatile for embedded projects. Their ultra-low-power modes and secure boot features make them well-suited for battery-powered devices requiring reliable connectivity and security. Additionally, Sipeed has launched the compact M0S module based on the BL616. With 4 MB flash, 512 KB SRAM, and USB 2.0 support, this tiny (11×10 mm) module is designed for ultra-low-cost IoT applications. With all these features, a board is available for a modest $4.

WCH CH32V003 Boards

The CH32V003 by WCH is the most cost-effective of this bunch, a 32-bit RISC-V MCU designed for industrial and general-purpose applications. It features a QingKe V2A core running at up to 48 MHz, 16 KB flash, and 2 KB SRAM. With support for multiple low-power modes, it is optimized for energy-efficient operations. It includes a 10-bit ADC, op-amp comparator, and standard interfaces such as USART, I²C, and SPI. The ultra-small package and 1-wire serial debug interface make it ideal for compact embedded systems, automation, and low-power IoT devices. The chip itself costs less than $0.20, and I was even able to spot a CH32V003 development board on AliExpress, being sold for less than $1 — a deal that’s hard to resist. By the way: In one of the next editions, author Tam Hanna will try out the CH32V003 and the corresponding IDE.

WCH CH32V307V-EVT-R1

The WCH CH32V307 on the CH32V307V-EVT-R1 board is a feature-rich RISC-V microcontroller designed for interconnected applications. It runs at up to 144 MHz, with a single-precision FPU and hardware stack area for improved performance. The controller includes 64-KB SRAM, 256-KB Flash, and a wide range of peripherals, such as eight UART ports, USB 2.0 HS, Ethernet with built-in PHY, and multiple timers. Its GPIOs can be mapped to external interrupts, and it supports ADC, DAC, SPI, and I²C interfaces, making it versatile for industrial automation, real-time data processing, and communication-centric tasks. Its efficient low-power modes and robust connectivity make it a solid choice for advanced embedded systems. You can find the dev board at different suppliers (including the Elektor Store) for around €20.

GigaDevice GD32VF103CBT6 Boards

The GD32VF103CBT6 microcontroller by GigaDevice can be found on development boards like the Sipeed Longan Nano and the LilyGo TTGO T-Display-GD32 RISC-V Development Board (available in the Elektor Store for a discounted price of just €12.95). Both boards are equipped with a small LCD and SD card socket, making all kinds of stand-alone devices possible. The 32-bit RISC-V CPU integrates a Bumblebee Core by Nuclei System, 128-K Flash and 32-K SRAM, an RTC, 3× USART and many other interfaces like USB, I²C, SPI, I²S and CAN.

Raspberry Pi Pico 2

Raspberry Pi surprised everyone by adding two Hazard3 RISC-V cores to the recent RP2350 powering the Raspberry Pi Pico 2! It offers 520 KB of SRAM, 4 MB of flash storage, 26 multi-purpose GPIO pins, including 4 that can be used for ADC, and a comprehensive set of peripherals including two UART interfaces for serial communication, two SPI plus two I²C controllers and 24 PWM channels. Additionally, the board includes 12 PIO (programmable I/O) state machines and a USB 1.1 controller with PHY supporting both host and device modes. Priced at only $5, the Pico 2 is perfect for learning and experimenting with RISC-V.

Right now, these are just the beginning of a small selection of RISC-V-based MCUs and CPUs. They range from Arduino Nano-grade MCUs to desktop and laptop-grade CPUs, and many more are expected to emerge in the coming years, reflecting the rapid growth and potential of the RISC-V ecosystem.

Editor's Note: This is an abbreviated version of the article, "The RISC-V Open-Source Processor Architecture" by Saad Imtiaz (Elektor) and Jean-François Simon (Elektor). The complete article (240736-01) appears in Elektor March/April 2025.

Questions About RISC-V or the Article?

Do you have questions or comments about this article? Email the authors at saad.imtiaz@elektor.com and jean-francois.simon@elektor.com, or contact Elektor at editor@elektor.com.