The Raspberry Pi line of tiny computers have made a big splash in recent years. For as little as $35 you can get a fully functional computer capable of running a variety of (mostly Linux-based) operating systems. Some models are even cheaper.
A bunch of competitors have entered the space, but like the Raspberry Pi, most similarly-priced models have processors based on ARM architecture.
Now Imagination Technologies and a startup named RIOS Laboratory are working on a new single-board computer with a RISC-V processor. It’s called PicoRio, and the first version is expected to launch in the fourth quarter of 2020.
While Raspberry Pi computers run open source, GNU/Linux distributions, every Raspberry Pi system to date has shipped with an ARM-based Broadcom processor featuring some proprietary components.
RISC-V is a free and open instruction set that anyone can use to design a processor. There are no licensing fees involved, and no aspects of the instruction set are off limits, which could make a Raspberry Pi-like computer with RISC-V more attractive to computer users, developers, and hardware hackers looking for a more open source solution.
According to the work-in-progress PicoRio user manual, the system will be a Linux-capable device aimed at developers who want to port software to RISC-V systems.
RIOS Laboratory says the plan is to “open source as many components as possible, including the CPU and main SoC design, chip package, and board design files, device drivers, and firmware,” although there will still be some exceptions including “foundry related IPs” and “commercial high-speed interfaces and complex commercial IP blocks like GPU.”
That said, the first PicoRio isn’t expected to be a particularly high performance device.
It’s expected to feature:
- 4 x RISC-V 64-bit CPU cores @ 500 MHz
- 1 x RISC-V 32-bit always-on core
- 512KB L2 cache
The processor is a 28nm chip, and the system will support LPDDR4 memory, USB 3.0, UART, I2C, and SPI interfaces. Storage will most likely be courtesy of a microSD card, and it’s unclear at this point what kind of video ports the computer will have.
The version that will ship this year won’t have a GPU. A model with an Imagination PowerVR GPU is expected to ship in 2021.