Ethernut
Ethernut one is open source hardware and software project to operate - Embedded - Ethernet systems and is mainly used in research and industrial applications.
Development history
After the rapid development of the Internet as a communication medium for human users, the idea of an Internet of Things appeared to many developers as a logical development. Thus, around the year 2000, several free and commercial projects were created with the aim of integrating embedded systems into existing TCP / IP networks. The challenge was that the 8-bit microprocessors common at the time rarely had more than 64 kilobytes of memory. The British developer Dave Hudson published the open source code of a real-time operating system kernel with an integrated TCP / IP stack under the name Liquorice in 2000 .
Another problem was that there was hardly any suitable hardware available at the time. Among other things, almost all available network controllers with a PCI bus were unsuitable for simple microcontrollers. A large number of free development tools already existed for the Atmel AVR microcontroller family and so in 2001 a first board based on the ATmega103 and an outdated, but still in production, Ethernet controller with ISA bus was published under BSD license . It is one of the pioneers of free hardware .
Hudson stopped working on Liquorice after a year. The source code was taken over into the newly founded Ethernut project to merge the free hardware and software. After initial publications in the AVR Freaks developer forum, the project switched to the SourceForge web portal in 2002 .
hardware
Four different reference designs (Ethernut 1, Ethernut 2, Ethernut 3 and Ethernut 5) are currently available as ready-to-use printed circuit boards.
The same functional assemblies are included in all versions:
- Ethernet interface
- RS232 interface
- Power supply
- Almost all of the microcontroller's I / O pins are available
The designs differ mainly in the microcontroller used (Ethernut 1 & 2: 8-bit AVR , Ethernut 3 & 5: 32-bit ARM ) and the memory availability. A slot for MMC memory cards is available from Ethernut 3 onwards.
software
Nut / OS
The operating system for the boards is called Nut / OS. It is a modular real-time operating system released under the BSD license .
Features:
- Cooperative multithreading
- Guaranteed interrupt response times
- Prioritized event handling
- Various configurable timers
- Dynamic memory management
- Process synchronization techniques
- Good portability to other architectures
Nut / Net
The network stack of the Ethernut software is called Nut / Net. It provides an extensive API for various protocols.
Supported protocols:
Configuration and Applications
Setting up Nut / OS and Nut / Net is very easy. After downloading the files, a configuration tool is executed which creates the libraries for the selected hardware after a few settings.
When programming the application in C , the Nut / OS and Nut / Net libraries are now used. The C standard library is also available to the application programmer. In addition to C, C ++ is widely supported. Furthermore, there is a Lua - interpreter so that Lua scripts can be run on the board.
Ethernut provides a large number of simple example programs to make it easier to get started with Nut / OS.
Supported Architectures
- Atmel AVR (e.g .: ATmega103, ATmega128, ATmega2561, AT90CAN128 and others)
- Atmel AVR32 (e.g .: AT32UC3A, AT32UC3B and others)
- ARM7 (e.g .: AT91R40008, AT91SAM7X, LPC-E2294, Gameboy Advance and others)
- ARM9 (e.g .: AT91SAM9260, AT91SAM9XE and others)
- ARM Cortex M (e.g. STM32, LPC17)
The following architectures are supported in principle, but are currently not actively maintained:
Bluetooth stack
The research group for distributed systems at ETH Zurich has developed a distributed sensor network with sensor nodes based on AVR. These sensor nodes communicate with each other via Bluetooth . The open source Bluetooth stack BTNut is used as the software basis . The BTNut stack is based on Nut / OS and extends it with Bluetooth functionality. Although the BTNut stack was primarily developed for the BTNode sensor nodes, the Bluetooth stack can also be ported to other applications.
distribution
Due to the early availability and the open concept of the hardware, Ethernut boards initially aroused interest in the research area, where various aspects of ubiquitous computing were dealt with . Among other things, it served as the first embedded platform for Contiki . The permissive license also makes commercial use less complicated and both hardware and software have found their way into numerous products.
According to its own statement, the German manufacturer, egnite GmbH, has sold around 33,000 Ethernuts so far (as of December 2013). Other manufacturers of compatible hardware are Achatz electronics (Netherlands), proconX (Australia), Propox (Poland), SOC Robotics (Canada), HW group sro (Czech Republic), thermotemp Embedded-IT (Germany). Furthermore, the Nut / OS operating system is used as the basis for the BTNode sensor network at ETH Zurich .
Similar devices
- Arduino
- Banana Pi
- BeagleBoard
- Cubieboard
- Intel Galileo
- Orange Pi
- PandaBoard
- Raspberry Pi
- Tinkerforge
Web links
swell
- ↑ Archive page with Ethernut as free hardware from 2001 ( Memento from February 10, 2001 in the Internet Archive )
- ↑ Archive link ( Memento of the original from September 23, 2015 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Marius Strobl et al .: Rapid Prototyping Embedded Systems Using Ethernut Boards (PDF; 981 kB)
- ↑ John Regehr, Usit Duongsaa: Preventing Interrupt Overload (PDF; 264 kB)
- ↑ M. Can Filibeli et al .: Embedded web server-based home appliance networks ( Memento of the original from January 17, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 832 kB)
- ↑ Adam Dunkels: Full TCP / IP for 8-Bit Architectures (PDF; 88 kB)
- ↑ Jan Beutel: Fast-prototyping Using the BTnode Platform ( Memento of the original from December 24, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 2.2 MB)
