SiFive and Arduino unveiled a wireless-enabled “Arduino Cinque” board based on SiFive’s HiFive, featuring a RISC-V FE310 SoC and an ESP32 wireless SoC.

At the Maker Faire Bay Area, Arduino joined with fabless RISC-V semiconductor firm SiFive to announce the first Arduino branded board using the open source RISC-V CPU architecture. There were few details on the Arduino Cinque, but judging from Cinque prototype photos below, it’s closely based on SiFive’s Arduino-compatible HiFive1 development board. There’s at least one key addition, however: an Espressif ESP32 SoC that supplies 2.4GHz WiFi and Bluetooth.

Front views of Arduino Cinque (left) and SiFive HiFive1
(click images to enlarge)

Like the HiFive1, the Arduino Cinque features SiFive’s MCU-like Freedom E310, the first commercially available RISC-V SoC. The 320MHz SoC “is one of the fastest microcontrollers available in the market,” says SiFive.

The Arduino Cinque appears to have the same footprint and pin configuration as the HiFive1, as well as a similar layout of the processor, micro-USB port, power jack, and wake and reset buttons. Other components differ, however.

Aside from its fast, open source processor, the HiFive1 is a fairly standard Arduino compatible. The 68 x 51mm board features 128Mbit off-chip SPI flash, 19x digital I/O pins, 9x PWM pins, an SPI controller, and 3x hardware CS pins.

Arduino Cinque rear view (left) and Freedom E300 block diagram
(click images to enlarge)

The HiFive1 is further equipped with a wakeup pin and 19x interrupt pins. A micro-USB port can be used for programming, debug, and serial communications, in addition to providing 5V power. The board can also draw power from a 7-12 DC input jack.

The HiFive1 can be programmed with the Arduino IDE, and ships with an open source Freedom E SDK that supports FreeRTOS. The Freedom E SDK page on GitHub mentions IDE support for Ubuntu.

The FE310 SoC that drives the HiFive1 and Cinque boards is equipped with 16KB L1, a 16KB Data SRAM scratchpad, and “hardware multiply/divide.” There’s also a debug module, “flexible clock generation with on-chip oscillators and PLLs,” and I/O support including UARTs, QSPI, PWMs, and timers.

SiFive is also selling the FE310 outright under an open source license, letting customers download their own RTL (Register Transfer Logic) onto the chips. However, the company is primarily building a “chips-as-a-service” customization business.

By combining a RISC-V with Espressif’s ESP32, Arduino and SiFive have served up two of the leading Cinderella stories in computing over the last few years. The ESP32 wireless SoC is a higher-end sibling to the ESP8266, and appears to be every bit as popular. It similarly supports either standalone operation or use as a slave device, for example as a subsystem incorporated into an Arduino board.

Espressif ESP32

Unlike the ESP8266, the ESP32 provides dual-mode Bluetooth 4.2 with legacy classic and LE (low energy) support. The SoC also offers faster, up to 150Mbps HT40 (40MHz channel width) 2.4GHz WiFi compared to the previous HT20 WiFi.

The Cinque unveiling followed SiFive’s announcement earlier this month of a new $8.5 million funding round. The Berkeley, Calif. based company, which is driven by the principal inventors of RISC-V including David Patterson, also released new tools that enable rapid evaluation of its “fully synthesizable” RISC-V SoCs. The tools support SiFive’s E31 and E51 Coreplex IPs on a $99 FPGA Digilent Arty development board.

The Arduino Cinque’s FE310 SoC is built on the 32-bit E31 Coreplex. The larger, 64-bit E51 Coreplex IP is similarly designed for MCU-oriented development environments rather than Linux. It has slightly better performance than the E31, and is primarily designed for use as a system or host control subsystem within a larger 64-bit SoC.

We have heard no updates on the more powerful, Linux-driven Freedom U500 SoC since SiFive announced it last July. The FU500 can integrate up to eight 64-bit, cache coherent “U5 Coreplex” RISC-V cores clockable today to 1.6GHz, and perhaps higher in the future. The 28nm fabricated U5 Coreplex supports the 64-bit RV64GC RISC-V architecture, and is aimed at machine learning, storage, and networking applications.

The Arduino Cinque is one of the first major announcements of the newly reunified Arduino, which had broken into rival camps for several years. Earlier this year, Arduino unveiled a Sigfox-ready MKRFOX1200 board.

“By partnering with a pioneer in open-source hardware, SiFive can further advance the progress of open custom silicon among makers, system designers and everyone else in between,” stated Jack Kang, VP of product and business development at SiFive. “We look forward to seeing the community’s reaction to the Arduino Cinque board, and believe that the Arduino concepts of openness and distribution mean that more people than ever will be exposed to RISC-V.”

 
Other Arduino announcements at Maker Faire

Arduino LoRay Gateway

Also at Maker Faire Bay Area, Arduino showcased its new Arduino LoRa Gateway and LoRa Node shields that run on Arduino boards. Due to arrive later this year, the boards will be offered in a LoRa Gateway Shield Kit for the Linino Linux-enabled Arduino Tian, and a LoRa Node Shield Kit designed for the Arduino Primo or other Arduinos with at least 32KB of flash.

In other Maker Faire announcements, Arduino announced the release of the open source Snap4Arduino blocks-based coding platform. This modification of the Snap! (formerly BYOB) visual programming language is designed for kindergarten through college computer education.

Arduino also gave an update on the Arduino Foundation, which was announced last October when the two feuding Arduino organizations announced their reunification. The Arduino Foundation’s main role is to maintain a unified IDE. The Foundation offers “a way to formalize the process, and give developers direct ‘ownership’ in the process,” says Arduino.

 
Further information

No pricing or availability information was provided for the Arduino Cinque. More information should eventually appear at the SiFive and the Arduino.cc websites.