Dual-Core Mastery: Unveiling the Raspberry Pi Pico 2’S Hybrid RISC Architecture

Everybody’s favorite microcontroller board is back and better than ever. Raspberry Pi Pico 2 sports a higher core clock speed, double the RAM of its predecessor, full backwards compatibility with existing Pico hardware and software, plus a dual-architecture design that lets users flip between ARM and RISC-V.

Pi Pico 2 is built on the new RP2350 microcontroller. It contains dual-core ARM Cortex-M33 and RISC-V Hazard3 150MHz CPUs, 520KB of SRAM memory, 4MP of QSPI flash storage, and new ARM TrustZone security architecture (ARM only). Although the 26-pin GPIO remains, there are now four 12-bit ADC pins.

These are substantial improvements—Pi Pico 2 is basically twice as powerful as the original Pico microcontroller board. Still, RISC-V is the biggest surprise. Users can jump into the two RISC-V cores at bootup and enjoy the full brunt of the Pi Pico 2’s hardware capabilities, minus the ARM security stuff, of course.

The RISC-V architecture is an open alternative to ARM and x86. Any company can dive into RISC-V without exposing themselves to the hellish patent landscape of Intel, AMD, ARM, Apple, and Qualcomm. If a CPU complies with RISC-V standards, it can run RISC-V applications. In theory, widespread adoption of RISC-V will lead to stronger competition and quicker innovation in the computer hardware industry.

Also, RISC-V follows longstanding Reduce Instruction Set Computer (RISC) principles. Applications built for RISC-V can be incredibly simple and efficient, thereby reducing the need for expensive, power-hungry CPUs. ARM is also based on RISC principals and enjoys similar architectural benefits.

The RISC-V ecosystem is still new, though. Eben Upon, co-founder of Raspberry Pi, made this point in a discussion with Jeff Geerling last year. “The RISC-V world is immature compared to the ARM world,” there’s a glaring “shortage of good, licensable high-performance [RISC-V] cores,” and the open-source philosophy has proven to be a hurdle for standardization.

A full pivot to RISC-V wouldn’t make sense for Raspberry Pi, at least not in 2024. However, a dual-arcitecture design in a simple machine like the Pi Pico is an interesting, compelling idea. Not only does it make RISC-V development more accessible, but it creates an environment where Hazard3 may enjoy mainstream use and standardization. By the way, Hazard3 was developed by Raspberry Pi’s Principal Engineer, Luke Wren, in his “free time.” Impressive.

You can purchase the Pi Pico 2 for $5. A wireless version, the Pi Pico 2 W, will arrive later this year with an Infineon 43439 modem.

Source: Raspberry Pi Foundation