SparkFun has officially launched the RED-V Thing Plus and RED-V RedBoard, a pair of Feather-compatible Thing Plus-footprint and Arduino Uno-format development boards based on the SiFive Freedom E310 RISC-V microprocessor core — making them, the company claims, "completely open source [...] from hardware to ISA."
"The SparkFun RED-V (pronounced 'red-five') Thing Plus is a low-cost, development board in our popular Thing Plus footprint and adds in the Freedom E310 core and RISC-V instruction set architecture (ISA)," SparkFun's product announcement explains. "What sets the RED-V Thing Plus apart is the completely open source approach from hardware to ISA. That means anyone can make full use the microcontroller without requiring royalties, licenses, or non-disclosure agreements.
"The on board Freedom E310 (FE310) is the first member of the Freedom Everywhere family of customizable SoCs from SiFive. Designed for microcontroller, embedded, IoT, and wearable applications, the FE310 features SiFive’s E31 CPU Coreplex, a high-performance, 32-bit RV32IMAC core. Running at 320+ MHz, the FE310 is among the fastest microcontrollers in the market. Additional features include a 16kB L1 Instruction Cache, a 16kB Data SRAM scratchpad, hardware multiply/divide, a debug module, 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 wide variety of applications can benefit from the FE310."
Before jumping into replacing existing Feather and Thing Plus boards with the RED-V, though, there are a few caveats to note. First, while the board comes with a Qwiic connector for SparkFun's solderless I2C interconnect ecosystem, the libraries are not yet available to make sue of it; second, the board can, at present, only be programmed through SiFive's Freedom Studio software or a Zephyr real-time operating system (RTOS) build environment.
The same technical details apply to the larger RED-V RedBoard, which swaps the Thing Plus form factor for one inspired by the Arduino Uno - and, indeed, SiFive's own HiFive1 FE310 development board. The RED-V RedBoard includes the same processor, USB Type-C connector, and as-yet unsupported-in-software Qwiic port, though also features a barrel-jack power connector and 5V-safe GPIO pins.
Full details are available on the RED-V Thing Plus and RED-V RedBoard product pages, where both boards are available to order priced at $29.95 and $39.95 respectively before volume discounts — the latter representing a considerable saving over the launch price of SiFive's earlier HiFive1.