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Posts Tagged ‘rust’

Tock Open Source OS for Secure IoT Systems Runs on Arm Cortex-M Microcontrollers

February 13th, 2018 No comments

We already have a fair share of open source operating systems running on Arm Cortex-M microcontrollers with FreeRTOS, mbed OS, Zephyr OS, RIOT, and many others. Earlier this morning, as I wrote about the Embedded Linux and IoT Summit 2018, I discovered you can now also add Tock to the list, with the operating system specifically designed for (secure) IoT on Arm Cortex-M MCUs.

According to the abstract, Tock aims to enable more secure and extensible IoT systems by using a language sandbox and hardware enforced mechanism to isolate third-party and other untrusted code in the system.

Tock Architecture

The operating systems is comprised of three components:

  • A trusted core kernel written in Rust language with a HAL, scheduler and platform-specific configuration
  • Capsules compiled with the kernel and use Rust’s type and module systems for safety; typically used for drivers & virtualization layers
  • User-space processes using the MPU for hardware protection at runtime; used for network stack, applications, etc…

System components (an application, driver, virtualization layer, etc.) can be implemented in either a capsule or process, but each mechanism trades off concurrency and safety with memory consumption, performance, and granularity.

Category Capsule Process
Protection Language Hardware
Memory Overhead None Separate stack
Protection Granularity Fine Coarse
Concurrency Cooperative Preemptive
Update at Runtime No Yes

Some of the supported hardware two board based on Microchip Atmel SAM4L Cortex-M4 MCU and Nordic Semi nRF51822 BLE Radio:

  • $60 Hail development module, based on Photon Particle form factor, and including a temperature and humidity sensor, light intensity sensor, accelerometer & gyroscope.
  • Upcoming $100 IMIX development board with the same sensors as Hail, but also adding an 802.15.4 radio, hardware RNG, USB host port, Arduino headers and more.

Click to Enlarge

You’ll find documentation, information about the hardware, and community links in TockOS website, or directly on Helena Project’s github account, where beside the source code for the project, you can also access tools, and the (EAGLE) hardware design files for IMIX board.

FOSDEM 2018 Open Source Developers Meeting Schedule

January 23rd, 2018 5 comments

FOSDEM (Free and Open Source Software Developers’ European Meeting) occurs every year on the first week-end of February, where developers meet for two days discussing about open source software projects. FOSDEM 2018 will take place on February 3-4 this year with  652 speakers, 684 events, and 57 tracks, an increase over  last year 608 speakers, 653 events, and 54 tracks. There will be 8 main tracks namely: Community, History, Miscellaneous, Performance, Python, Security and Encryption, Space, and Global Diversity CFP Day.

There will also be 33 developer rooms, and since the full schedule is now available, I’ll make a virtual schedule mostly based on sessions from the Embedded, mobile, and automotive, Hardware Enablement, and Internet of Things devrooms.

Saturday 3, 2018

  • 09:50 – 10:15 – Turning On the Lights with Home Assistant and MQTT by Leon Anavi

In this presentation you will learn the exact steps for using MQTT JSON Light component of the open source home automation platform Home Assistant for controlling lights through the machine-to-machine protocol MQTT. Practical examples for low cost devices combining together open source hardware with free and open source software will be revealed. The presentation will provide general overview of Home Assistant, details about the software integration of new devices to it through the MQTT protocol and open source MQTT brokers such as Mosquitto. We will do a code review of an open source Linux daemon application for Raspberry Pi, written in the C programming language and based on the Paho library for MQTT client and the piGPIO library used for pulse-width modulation (PWM) control of a RGB LED strip. We will compare it to an implementation of the same features for the microcontroller with WiFi ESP8266 written as a sketch for the Arduino environment. Furthermore, the presentation will include details about reading data from various sensors and their setup in Home Assistant.

  • 10:25 – 10:50 – Accessing your Mbed device from anywhere using Pagekite by Bert Outtier

When looking at home automation solutions available in the market nowadays, one of the most important and expected features is to be able to control your home automation installation from anywhere in the world using a smartphone app. A vendor of a low-cost home automation solution requested us to add such a feature to their existing IP gateway product, which only allowed for users to control their home automation system with their smartphone while they are connected to their local network at home. We were asked to make it possible to let the smartphone app connect to the IP gateway from anywhere in the world. This vendor’s IP gateway hard- and software was based on the Mbed platform, so they needed a solution that could fit within Mbed.

Since our client wanted an open-source, secure, low-cost and easy to set up solution that he could host himself, we opted to go for Pagekite. However, since Mbed does not support OpenSSL, Linux sockets or libev, the existing libpagekite C library was not an option to start from. So we started to implement a Mbed flavour of the library ourselves, and decided to make it open-source

  • 11:00 – 11:30 – The free toolchain for the STM8 by Philipp Klaus Krause

The STM8 is a popular 8-bit architecture by ST Microelectronics commonly used in household electronics, automotive application and industrial controls. For quite a while there were no free tools, and the irregular architecture makes it hard to support in GCC or LLVM. In recent years free tools for it started to appear and now form a free toolchain that surpassed preexisting non-free ones. The most important part is the Small Device C Compiler (SDCC). New tree-decomposition-based algorithms from recent compiler research have been implemented in SDCC, including a new register allocator particularly suited to irregular architectures with few registers. SDCC quickly surpassed the non-free compiler in standard compliance and OS support and generates substantially faster integer code. Programs can be flashed by stcgal (via a serial link on STM8 devices that have a bootloader) and stm8flash (via the SWIM interface of ST-LINK hardware). OpenOCD and GDB allow on-target debugging via the ST-LINK. IDEs complete the development environment. However, stcgal still needs non-free binary blobs for use with some devices and the ST-LINK has non-free firmware. SDCC still falls short in floating-point performance. While there are some ports of free RTOSes that use the free toolchain for the STM8, more would be desirable.

  • 11:30 – 12:00 – Building RT Linux distribution with Yocto by Pierre Ficheux

The conference will describe how to use PREEMPT_RT and Xenomai with Yocto build system – building image and SDK – developing simple application – testing performances.

Using RT extension with Yocto is not that easy because linux-yocto-rt kernel is not usable on main embedded target such as ARM (as it works on QEMU target only). Using Xenomai is much more complicated as it needs several steps (patching the kernel, installing user-space libraries, building an extended SDK).

During the conference we will describe how to build a Yocto Linux image using PREEMPT_RT for famous boards such as Pi 3 or BeagleBone Black.

Some Xenomai support is provided by meta-eldk from DENX but it supports only Xenomai 2.6. We will describe meta-xenomai as we maintain it for our customers (available on GitHub). That new meta-xenomai layer is based on Xenomai 3.x and very recent kernel.

Then we will explain how to build a simple Xenomai application based on a periodic task. Finally we will compare performances of both extension (PREEMPT_RT and Xenomai) on same hardware.

  • 12:00 – 13:00 – How to keep your embedded Linux up and running? by Krzysztof Opasiak

Userspace software is imperfect and we all know about this. Running it for 5 minutes seems to be easy but what about days or weeks? This problem already gave server guys a lot of sleepless nights. Nowadays also IoT and embedded Linux world is facing very the same problem. Unfortunately solutions known from server world (Nagios and friends) usually cannot be directly applied.

During this talk, Krzysztof will discuss problems related to monitoring and “healing” embedded Linux distribution. First, most common server approaches will be described. After that, Krzysztof will try to identify key problems of applying this solution to embedded platform. Then Krzysztof will introduce faultd – small but extendable daemon for system monitoring and CPR;). How to use it? What can it do? What are the advantages and disadvantages? All those questions should be answered in this part. Last part is going to be a discussion on a presented idea and experience sharing.

  • 13:05 – 13:30 – A Guided Tour of Eclipse IoT: 3 Software Stacks for IoT by Benjamin Cabé

Whether you’re looking at the constrained devices that make for the “things” of the IoT, gateways that connect them to the Internet, or backend servers, there’s a lot that one needs to build for creating end-to-end IoT solutions. In this session, we will look at the typical software features that are specific to IoT, and see what’s available in the open source ecosystem (and more specifically Eclipse IoT) to implement them. A live demo of the Eclipse IoT Open Testbed for Asset Tracking will allow the audience to see some of the projects (such as Eclipse Kura, or Eclipse Kapua) in action.

  • 13:45 – 14:10 – Tizen:RT A lightweight RTOS platform for low-end IoT devices by Philippe Coval

The Tizen software platform has been designed to target consumer electronics, since 2013 the OS is powering many products on the market (from smart watches to TVs, cameras or even white goods). Even if this Linux based platform is very flexible, the Linux kernel has minimum size requirements, so Tizen can’t be deployed on constrained devices (ubiquitous microcontrollers).

To also target low end devices part of Tizen’s technology was rebased on NuttX RTOS. Seamless connectivity is still provided by IoTivity, while a new IoT features are becoming available to application developers too, this whole stack is Tizen:RT!

This presentation will give an overview of Tizen ecosystem, and explain how to get started with Tizen:RT using QEmu, SDK, finally an IoT scenario will be demonstrated on trusted system on module ARTIK 055s.

  • 14:25 14:50 – Eclipse IoT FOSS Platform for Cloud Based IoT Solutions by Steffen Evers

It is expected that in the next years billions of devices will be connected to the Internet of things (IoT). Many of them will interact with cloud-based solutions to provide additional services on the devices or in the web. To bring IoT to the next level technologies for supporting cross-domain/cross-vendor solutions are needed. There is already a lot FOSS available to provide a technological base for building IoT solutions (e.g. Kubernetes). However, on top of it, software is needed for the connectivity challenges, support of domain-specific protocols, large scale messaging and device management and integration with existing infrastructure. Eclipse IoT aims to address these needs and provide an FOSS IoT framework that makes IoT development fast and simple. In the last year Eclipse IoT has made a lot of progress and the underlying environment in cloud technology has seen a lot of changes. In addition, upcoming challenges like automated driving and connected vehicles have resulted in new projects for better support for the automotive domain. This talk gives you an overview of major Eclipse IoT projects and illustrates its capabilities with a short demo.

  • 15:05 15:30 – IoT.js – A JavaScript platform for the Internet of Things by Ziran Sun

IoT.js is a JavaScript platform that aims to provide inter-operable services for IoT world. Powered by JerryScript, an ultra-lightweight modular JavaScript engine, the platform is designed to bring the success of Node.js to constrained IoT devices. To address interoperability, IoT.js has provided a Node.js friendly architecture and comes with a subset of Node.js APIs. Since Samsung OSG first presented IoT.js in FOSDEM in 2016, the platform has been through a rapid growth in last couple of years. With a lot active high-quality contributions from the IoT.js and JerryScript open source community, IoT.js has released version 1.0 in July 2017 which presented a rich set of features, hardware and tool supports for developers. In this talk, we are looking at recent developments in IoT.js and share our vision for future plans. The talk is supported by a demo of iot.js running on constrained device seamlessly connects to node.js for third party cloud access.

  • 15:45 – 16:10 – The dark side of Internet of things by Dipesh Monga

With the advent of the Internet of things, monitoring and controlling everything such as coffee maker, lights, TV, Fridge,etc. over the Internet has become a child’s play. But are we really making our lives simpler or diving ourselves in a vast ocean which is getting deeper and deeper? In today’s world where the security of our data of a major concern, the number of websites are always tracking what we search for, what we watch, our location and now when things are limited to only data, adding another dimension i.e. physical entities is really a big question.

From this talk audience will take away an understanding of the privacy concerns related to IoT, and how they may be putting their personal information at risk by connecting my physical entities to the Internet. Is it really safe to connect things to the Internet?

  • 16:30 – 17:00 – Facing the Challenges of Updating Complex Systems by Enrico Jörns

Over the past three years, the growing zoo of Open Source update frameworks made updating an embedded Linux system much easier. But, the availability of a robust update tool solves only one step in the complex chain from a software artifact to an updated and working system on your devices.

Starting with a modern system consisting of a recent bootloader, kernel, init system and update tool, this talk ventures beyond the basic and already solved topics of A/B redundancy, atomicity, or simple update verification.

Enrico will present strategies for creating a robust update chain from automated testing up to full rollout management and show how to solve these challenges with recent Open Source software such as barebox, RAUC, systemd, hawkBit, casync and labgrid. You will learn how to deal with more modular and complex system setups, restricted systems, error recovery, product variants, resigning for deployment, updating the bootloader itself and interaction with verified boot.

  • 17:00 – 18:00 – Multitasking on Cortex-M class MCUs, A deep-dive into the Chromium-EC OS by Moritz Fischer

We’re gonna look at multi-tasking on small Cortex-M class MCUs like the ARM Cortex-M0. After a brief general overview of the Cortex-M0 programming model, exception handling and other basics required, we’ll start our deep-dive into one specific implementation in the Chromium-EC firmware. We’ll look at startup code, how tasks are implemented, how to deal with priorities and peripheral interrupts.

The Chromium-EC firmware is a little (RT)OS that runs (mostly) on ARM cores of the Cortex-M class (M0/M3/M4), and powers Google’s Chromebooks as well as other devices (Project Sulfur SDR). It’s permissive license makes it attractive for (ab)use in other projects, since Kernel and U-Boot integration are already existing.

  • 18:00 – 18:30 –  The Chromium project’s Way to Wayland by Maksim Sisov

Wayland is the most advanced X11-alternative display protocol, shipping today in a variety of desktop and embedded environments. Although the Chromium browser on Linux still defaults to use the X11 window system, there have been efforts to port it to different environments.

This effort happens in various fronts, including the development and stabilization of Ozone, an abstraction layer for graphics and input events, and the transitioning of some ChromeOS-oriented solutions to Linux, for example Chromium’s new “UI service”.

Igalia has been actively contributing to this multi organizational collaboration, aiming at getting a full fledged Chromium browser running natively on Wayland. The work happens on Chromium’s upstream repository so that the greater Chromium community can benefit from it.

  • 18:30 19:00 – GStreamer for tiny devices by Olivier Crête

GStreamer is a complete Open Source multimedia framework, and it includes hundreds of plugins, including modern formats like DASH, HLS or the first ever RTSP 2.0 implementation. The whole framework is almost 150MB on my computer, but what if you only have 5 megs of flash available? Is it a viable choice? Yes it is, and I will show you how.

Starting with simple tricks like only including the necessary plugins, all the way to statically compiling only the functions that are actually used to produce the smaller possible footprint.

Sunday 4, 2018

  • 09:30 10:00 – Programming UEFI for dummies, what I have learned while tweaking FreePascal to output UEFI binaries by Olivier Coursière

With the upcoming end of legacy mode in UEFI firmware on PCs, every alternative and hobbyist operating systems, bare metal programmers and wannabe OS developers will have to deal with UEFI on modern hardware. After presenting the binary format of UEFI applications, I will focus on the use of UEFI APIs through EFI system table and UEFI protocols so you can get started.

  • 10:00 – 10:30 – Rustyarm AKA A project looking at Rust for Embedded Systems by Benedict Gaster (cuberoo_)

Rustyarm is a project in the Physical Computing group at the University of West of England looking at application of Rust on embedded micro controllers. UWE Sense is a new hardware and software platform for IoT, build with ARM micro controllers, Bluetooth LE and LoRaWAN, which runs a software stack written completely in Rust. While UWE Sense is a close to the metal implementation, UWE Audio, a new hardware platform for studying high performance audio using ARM micro controllers, uses Rust to implement a monadic reactive graph, supporting both an offline compiler and and Embedded DSL. UWE Audio uses safe Rust, for example, describing domain clock as generic associated types, providing both compile time guarantees that multiple streams will not be incorrectly sequenced at different sample rates, and the ability to dynamically compile for different parts of the system.

In this talk I will provide a high-level overview of the Rustyarm project, including how using Rust has made this project interesting, but also enabled providing guarantees with respect to the audio scheduler, for example. However, Rust has some short comings in the embedded domain and we provide details on some of these and what we and the wider community are doing to address them. As an example of Rust’s application in the embedded domain we present early work on UWE Audio and hardware and software platform for building digital music instruments, which as already noted is programmed with solely in Rust.

  • 10:30 – 11:00 – How to build an autonomous robot for less than 2K€ by Miika Oja (PuluMan)

Telepresence, Delivery Boy, Security and Follow Me in one PULUrobot. PULUrobot solves the autonomous mobile robotics complexity issue without expensive parts, without compromise. By fearless integration and from-scratch design, our platform can do SLAM, avoid obstacles, feed itself, and carry payload over 100kg, for less than 2000EUR.

Application ecosystem can be born around it, as we offer a ready-made Open Source (GPLv2) solution in a tightly coupled HW-SW codesign. Pulu Robotics Oy was founded in July, 2017, in Finland, to solve our own needs, with an efficient team of three. No one had prior knowledge on robotics.

By studying the market and other startups, we realized the common mistake is to use “robotic modules” as building blocks. They are highly expensive, provide little bang for buck, often are inefficient, and require complex software middleware (such as ROS) as the glue inbetween. Due to our combined background in mechanical, electrical, software and manufacturing design, we took the approach of designing as much as possible by ourselves.

We are now selling the very first generation of robots for the early adopters, hoping to give a kick start to the open source community as soon as possible. Behind the curtains, we are focusing on the development of our next 3D sensor system, which will replace the current scanning 2D lidar with a 360×90 degree full 3D distance data, and do it for the same price we currently pay for the Scanse 2D lidar used in the first small-scale production batch.

  • 11:00 – 11:30 – … like real computers! Making distributions work on single board computers by Andre Przywara

Installing an operating system on single board computers (SBCs or “Fruit-Pis”) is very board specific and requires a lot of hand holding. If at all, standard distributions support only a small number of them explicitly, which leads to a lot of board specific images and distributions. This talk will show how this situation can be improved, to the point where off-the-shelf Linux (or BSD) distributions can be installed on those boards, without those distros knowing about each and every one of them. Key ingredients are standardized firmware interfaces like UEFI, stable device trees and on-board memory like SPI flash. This should make using ARM based SBCs as easy as using (x86) PCs today: like “real computers”. On top of this, ways to simplify and speed up mainline Linux kernel support are explored. Enabling kernel support for new SoCs usually takes a while, especially if the effort is driven by the community. This delays distribution support, up to a point where a certain SoC or board might become slightly dated when it’s finally supported. Using more device tree features and less hardcoded kernel data would reduce the code required to support new SoCs, ideally reaching a point where new SoCs could be at least booted with existing (distribution!) kernels, just by providing the proper device tree blob. This talk describes the idea and gives an example by looking at what can be done on Allwinner SoCs.

  • 11:30 – 12:00 – Booting it successfully for the first time with mainline by Enric Balletbo Serra

While things have gotten a lot better, new hardware bring-up sometimes still feels like pulling teeth. With the right methodology, tools and techniques, a significant amount of time, energy (and sanity) can be saved while enabling a new board to run Linux. In this talk, we’ll discuss the phased process involved in new board bring-up and the challenges it can pose, from reviewing initial schematic design to the successful upstreaming of any necessary bootloader and kernel patches. We’ll also provide some examples of the process based on a board that was recently made compatible with mainline.

  • 12:00 – 12:30 – SITL bringup with the IIO framework, bootstrapping a x86 based drone platform by Bandan Das

This talk aims at an introduction to using the Industrial IO(IIO) framework to initialize sensors and acquire data to feed to a Software in the Loop (SITL) interface of drone software such as iNav/Cleanflight. Most flight controller boards are based on low power ARM microcontrollers and the flight controller software is not usually based on Linux. However, with the availability of increasingly powerful boards with onboard sensors and multicore processors, using a Linux based flight controller software can be used to our advantage. Experimenting with onboard devices and scheduling algorithms can lead to interesting applications with minimal porting overhead to new architectures.

The talk starts with a quick overview of the IIO framework and using it to initialize the drivers for the onboard sensors of the Intel Aero platform, a x86 based flight controller board. Although, not tied to the Aero board in any way, this talk will use this board as an example to describe the onboard sensors and acquire data from them to successfully run a minimal SITL instance. The talk aims to explore how the IIO framework exposes data from these sensors and how users can utilize these interfaces followed by a demo of the setup.

  • 12:30 – 13:00 – Rapid SPI Device Driver Development over USB by Stefan Schmidt

On the quest for a cheap and easy way to connect some simple SPI devices to my laptop it was surprising to not find anything suitable available. The idea is neither new nor innovative and surely there must have been something already.

Maybe the use-case was to special. To connect the SPI device to a Linux laptop over USB in order to develop a SPI kernel driver for it and having a rapid development and test cycle. None of the solutions to access the SPI device over libusb in userspace would work for me. I needed a SPI master controller in kernelspace to work with the variety of devices and kernel subsystems.

After some research I settled on the MCP2210 chip. With its cheap and easy to get development boards and an out-of-tree driver as a good start. Maybe it is also something others are looking for and it is surely worth demonstrating and explaining.

  • 13:00 – 14:00 – Implementing state-of-the-art U-Boot port, 2018 edition by Marek Vasut

This presentation is a practical guide to implementing U-Boot port to a new system from scratch. U-Boot is the de-facto standard bootloader for embedded systems, there is plenty of U-Boot ports, yet vast majority of those are implemented in sub-optimal way. This talk first explains the U-Boot internals, the driver model (DM) and it’s interaction with device tree (DT), as understanding these is vital to understanding the implementation of core subsystems. The core subsystems are explained in detail afterward to allow developers implement drivers the intended way without hacks and workarounds. Unfortunately, not all systems have plenty of resources, but U-Boot caters for those as well. The final part of the talk discusses the U-Boot SPL, the preloader which initializes the hardware, DRAM and starts U-Boot and finer parts of this procedure, which tends to have plenty of pitfalls.

  • 14:00 – 15:00 – Image capture on embedded linux systems by Jacopo Mondi

Image capture is one of the most broad and complex fields of today’s computing applications. Capturing and displaying images with an embedded platform poses additional challenges, introduced by the rapidly increasing complexity of dedicated hardware blocks often found on modern Systems On Chip designed for mobile and industrial computing. Using real world examples of image sensors, connection buses and processing blocks this presentation provides an overview of current industry standard technologies with an introduction to Video4Linux2 kernel framework for driver development and its userspace APIs.

  • 15:00 – 16:00 – ARM64 + FPGA and more: Linux on the Xilinx ZynqMP by Luca Ceresoli

The Xilinx Zynq UltraScale+ MPSoC (aka ZynqMP) is a powerful and complex chip featuring 64-bit cores, 32-bit realtime cores, a large FPGA, a GPU, video codecs and dedicated power management and security units.

The main topics covered will be:

  • Overview of the hardware.
  • Available software support from Xilinx and from the community.
  • How the peculiar CPU+FPGA design effectively allows to design “your own SoC”, with the technical steps to implement this with Linux.
  • Why booting is nontrivial on this SoC and the currently available ways to boot Linux.
  • Handling the H.264/H.265 hardware codecs.
  • GPU support issues.

Focus will be given to how much open source technologies can be used with the ZynqMP SoCs, why this matters, and the current status of open source resources with respect to the alternatives.

  • 16:00 – 16:50 – New GPIO interface for linux user space by Bartosz Golaszewski

Since linux 4.8 the GPIO sysfs interface is deprecated. Due to its many drawbacks and bad design decisions a new user space interface has been implemented in the form of the GPIO character device which is now the preferred method of interaction with GPIOs which can’t otherwise be serviced by a kernel driver. The character device brings in many new interesting features such as: polling for line events, finding GPIO chips and lines by name, changing & reading the values of multiple lines with a single ioctl (one context switch) and many more. In this presentation, Bartosz will showcase the new features of the GPIO UAPI, discuss the current state of libgpiod (user space tools for using the character device) and tell you why it’s beneficial to switch to the new interface.

FOSDEM 2018 will take place at the ULB Solbosch Campus in Brussels, Belgium, attendance is free of charge, and no registration is required.

$35 Tessel 2 IoT Board Features Atmel SAMD21 MCU and Mediatek MT7620n WiSoC

March 10th, 2015 3 comments

Tessel is a Wi-Fi IoT board based on NXP LPC1830 Cortex M3 MCU and Texas Instruments CC3000 modules, that’s designed to bring embedded development to web programmers with a system that can be programmed with JavaScript and Node.js.  At the time of the crowdfunding campaign in 2013, the board was available with external modules (Relays, sensors, Bluetooth LE…) for $100 and up, but now Technical Machine, the company behind the project, has announced Tessel 2 combining Atmel SAMD21 Cortex M0+ to control I/O and Mediatek MT7260n for Wi-Fi connectivity, still programmable with JavaScript ot Node.js.

Tessel_2Tessel 2 specifications:

  • MCU – Atmel SAMD21G14A-MU Cortex M0+ MCU @ 48MHz with 16KB SRAM and 2KB Flash
  • SoC – Mediatek MT7260n MIPS24KEc Wi-Fi SoC @ 580 MHz
  • System Memory – 64MB DDR2
  • Storage – 32MB flash for firmware (OpenWRT)
  • Connectivity – 10/100M Ethernet, and Wi-Fi 802.11 b/g/n with dual PCB antennas
  • USB – 2x USB 2.0 host ports + 1x micro USB port for power and programming
  • Expansion – 2x Tessel module ports (10-pin headers) connected to SAMA21 MCU.
  • Power – 5V via micro USB.
  • Dimensions – N/A

OpenWRT (Linux) runs on MT7620n with io.js, an npm compatible platform originally based on node.js, which you can access with tessel command, or if you’re used to Linux, just as a standard OpenWRT router. While a custom firmware runs SAMD21, and both OpenWRT and Atmel firmware source code is available on github in respectively openwrt-tessel and v2-firmware repositories. Performance of the JavaScript engine is said to be 20 times better than on Tessel 1. Linux also brings more flexibility than the closed firmware found on CC3000, and Python and Rust programming languages have been added.

Rust Code Sample on Tessel 2

Rust Code Sample on Tessel 2

Most external modules for Tessel 1 are supported on Tessel 2, but the company has decided to get rid of some Tessel modules like Camera, Bluetooth LE, or micro SD card, as USB dongles with these functionalities already exist at a cheaper price, and only kept low speed Tessel module such as sensors, relays or servos since they are better suited to the I/O capabilities of an MCU. Check out the list of Tessel & USB modules for details.

Tessel 1 costs $75, and despite being more powerful Tessel 2 only costs $35 for single order. The great thing is that if you have a small scale project (10 units or more), they can customized manufacturing for example by leaving the Ethernet RJ45 connector and USB connectors unpopulated, and adding Tessel or USB modules. Price goes down with volume, and for order over 1,000 unit, Tessel 2 will cost less than $30.

Tessel 2 is up for pre-order until April 4 (for the first batch) on tessel.io, but the downside is that the boards are only expected to ship in August 2015.