Cam-equipped dev kit runs Linux on NPU-equipped Allwinner V831

Cam-equipped dev kit runs Linux on NPU-equipped Allwinner V831

Jan 6, 2021 — by Eric Brown

— 699 views

Sipeed’s $28.80 “Sipeed MAIX-II Dock” dev kit runs Linux on a MAIX-II module with a 1GHz Cortex-A7 Allwinner V831 SoC equipped with a 0.23-TOPS NPU and 64MB DDR2. The Dock adds a 2MP HD camera, WiFi, 2x USB Type-C, and more.

Sipeed has launched a second-gen, AI-enabled MAIX-II module that runs Linux. The module is avaialable on a Sipeed MAIX-II Dock development kit that extends it with a camera, WiFi, and other features. Designed for deep learning vision applications, the SBC is available for $28.80 at Seeed.

Sipeed MAIX-II Dock (left) and MAIX-II module
(click images to enlarge)

The MAIX-II follows Sipeed’s MAIX-1 (M1n) module, which appeared on a similarly camera equipped Sipeed MaixCube dev kit. The MAIX-I is built around a RISC-V architecture, MCU-like Kendryte K210 SoC with 1-TOPS NPU. The K210 nominally runs a stripped-down NOMMU Linux distribution but is ideally designed to run FreeRTOS.

The MAIX-II replaces the K210 with an Allwinner V831 IP Camera SoC that runs a full Linux distribution. We saw the SoC last year on Sochip’s camera equipped V831 development kit. The Allwinner V831 is a lower-powered alternative to the Allwinner S3, which powers Pine64’s PineCube camera dev kit.

Allwinner V831 IP Camera SoC block diagram (left) and MAIX-II detail view
(click images to enlarge)

Although the V831 SoC on the Sochip kit topped out at 800MHz, Sipeed claims up to 1GHz speed. As with the S3, there is no 3D GPU, but you get a robust ISP and a VPU capable of dual-stream or HD video. H.264 encoding supports up to 1080p@30fps video and H265 at up to 1080p@30fps. The V831 integrates a 0.23 TOPS (200 GOPS) NPU compared to 0.1-TOPS AI chip on the MAIX-I. The SiP implementation also integrates 64MB DDR2 RAM.

The MAIX-II module, which connects to the dev kit via an M.2 interface, provides 16MB of optional flash and a 10/100 Ethernet controller. The 24.9 x 22.1mm module offers I/O including dual-lane MIPI-CSI and an 8-bit LCD interface for up to a 10-inch display. Other I/O includes 2x SPI, 4x I2C, 2x SMHC, and single I2S, line-out, mic-in, and 6-bit LRADC “for key.”

Sipeed MAIX-II Dock
(click image to enlarge)

The Sipeed MAIX-II Dock is equipped with a 2-megapixel, 1080p30 Omnivision SP2305 (PDF) sensor. The camera has an M12 lens with 6mm default focal length and connects to the board via a B2B connector.

The 48.9 x 33.9 x 36.1mm Sipeed MAIX-II Dock communicates via a 2.4GHz 802.11n Realtek RTL8189FTV module and antenna. Other features include a 1.3-inch 240 x 240 IPS display, a 1W speaker, a mic, a microSD slot, and an accelerometer.

Sipeed MAIX-II Dock bottom view showing display (left) and detail view
(click images to enlarge)

Dual USB Type-C ports include an OTG port and a debug port, each of which supports 5V power input. The board also provides dual 10-pin GPIO connectors plus user and reset buttons. The Dock has a 35 to 65℃ operating range and runs at 490mA under load.

The OpenWrt-based MAIX-LINUX firmware integrates python3.8.5 and a Jupyter Notebook based development environment. The distro is optimized for the 2.3-TOPS NPU and offers drivers for all onboard resources.

The CNXSoft post that alerted us to the product notes that Sipeed has teased a MAIX-III module with a 1.5-TOPS NPU, dual-band WiFi, GbE, and 512MB to 2GB DDR3. Due in February, the module runs on a Linux-ready SoC that could be a Rockchip design.

It is unclear if the Sipeed MAIX-II Dock is an open hardware project with posted schematics like the Pi-like, Zynq-7020 based Sipeed TANG Hex SBC. Sipeed is also working on an unnamed, $12.50 dev kit for a new Allwinner/Alibaba T-Head SoC collaboration called the XuanTie C906. The single-core, RISC-V-based SoC and SBC are due to launch later this month.

Further information

The Sipeed MAIX-II Dock is available on preorder from Seeed for $28.80, with shipments due Jan. 15. More information may be found at the Seeed shopping page.