A Review: Ben NanoNote Gets Small with Embedded Linux


Qi Hardware is now shipping its first “copyleft hardware” device, the ultra-portable Ben NanoNote.

The palm-sized notebook is designed to be a hackable hardware platform for Linux developers, akin to what the Arduino board is for electronics projects. Key to making that vision a reality is keeping every part of the product open: the circuit board designs are licensed for reuse, every chip included uses open-source drivers — and the system, of course, runs embedded Linux.

Qi Hardware was founded in 2009 by several former developers and engineers from the Openmoko project, which initially set out to build a completely-free Linux-based mobile phone, but has since turned its attention to other projects. Qi’s business model and product roadmap is decidedly more incremental than Openmoko’s, perhaps reflecting lessons learned from the previous company. Qi is self-funded; the plan is to use proceeds of Ben sales to fund the development on the next NanoNote revision as well as other projects.

The name “Ben” is the Chinese word for “origin,” and marks Qi Hardware’s first product to market. It is available for order at US$99, directly from the nanonote.cc site, in individual units and in quantities of ten.

The Ben is not designed to be a mass-marketed consumer electronics product; instead, the goal is to inspire the creative developer who sees the hardware and thinks, “I could do something with that.” To that end, even though the Ben model is modest in its processing power and screen resolution — two factors consumer electronics devices lean heavily on — it is built around specifications that the Linux hacker will appreciate. It includes a full QWERTY keyboard, USB Host, a MicroSD card slot supporting SDIO, serial console connection inside the battery compartment, and uses a kernel, bootloader and root file system that can be flashed over the USB port.


The hardware is based around a 366 MHz MIPS processor, 32MB of RAM and 2GB of Flash storage. The case is a notebook-style clamshell design a mere 10-by-7.5 cm in size; the screen is a 320×240 full-color LCD and the audio includes a built-in speaker and microphone as well as a standard stereo headphone connector. Power can be provided by a 3.7V Li-ion battery (compatible with the batteries used in Nokia phones), or over the mini-USB port. There is no built-in networking, but the micro-SD storage card slot supports several SDIO WiFi cards, and USB-to-Ethernet adapters have been tested to work with the USB port.


The software is based on the OpenWrt Linux distribution popular on many consumer WiFi routers. According to developer Wolfgang Spraul, the project examined several other embedded Linux platforms — including OpenEmbedded, buildroot, and Debian — but he wanted to start with OpenWrt based on his prior experiences at Openmoko. Nevertheless, OpenWrt is not the only option: both OpenEmbedded- and Debian-based distros for the NanoNote are works-in-progress within the community.

The latest builds run the 2.6.32 Linux kernel, the uboot bootloader, Busybox, and a suite of text-mode applications already built for OpenWrt. There is no closed, binary-only firmware on the system, and detailed specifications (including, data sheets, pin-outs, and circuit diagrams) are available on the wiki for the entire device.

The Ben is perfectly capable of running graphical applications — including the GTK+ and Qt toolkits — through the DirectFB framebuffer interface, which provides a less resource-intensive GUI layer than a full X Window server.  A wide variety of user applications are under development by the community, including some that lean towards embedded device usage (such as the Rockbox digital music player and Vido offline-Wikipedia reader) and some flashier options, such as Quake and Doom.

Customize and Extend

Copyleft hardware means more than just purchasing the device from the manufacturer and customizing the software, however. The board schematics are available under the Creative Commons Attribution-Share Alike license, which ensures that anyone can legally manufacture a variation of the device, provided that they also publish their schematics under a copyleft license — just as the GPL requires of software derivatives.

Copyleft hardware is not nearly as widespread as copyleft software; the Qi Hardware cites just four other projects that follow the same approach: the Elphel digital camera,Pandora game console, the Milkymist One visual-effects video synthesizer, and the Arduino microcontroller. The Arduino’s success in particular is an example of what the team behind the Ben hopes to see develop around its NanoNote project.

According to Mirko Lindner, what makes the NanoNote an attractive platform on which to build a range of Copyleft products its its flexible form-factor.  “At the end of the day any product is defined by its case. If you take the Ben for example, if you were to connect a different screen and attach it to the board facing up and create a shell around it, you would have a digital picture frame without really having modifying the board.”

Individuals or a project community may come up with desirable products that can be based on NanoNote hardware, royalty-free, as could companies. The Qi Hardware wiki collects project ideas and use cases, as do the developer and discussion mailing lists. The concepts range from copyleft-alternatives to closed consumer devices like music players and calculators to customized tools for education, travel or industrial use.

Lindner said that Qi is interested in discussing involvement in collaborative hardware projects from communities or companies if approached but is committed to copyleft in hardware as well as software. Qi has already come out with two development boards, the AVT2 RC1 and RC2, each of which builds on the platform used in the Ben and has begun planning for the second iteration of the NanoNote, to be named the “Ya” (meaning “graceful”).

Even more interestingly, the first externally-developed project based on the Ben has already appeared: Carlos Camargo’s Swiss Army Knife Card, which adds a field-programmable gate array (FPGA) and is used for analog signal processing.  For a product that has been available to the public for just over one month, that displays considerable promise.