Written by Adam Dunkels,
Saturday, 06 September 2008
We are happy to announce the release of Contiki 2.2.1! The focus of this release is to fix bugs found in the 2.2 version. The changes are: significant bugfixes and performance improvements to the data collection protocol; improved data presentation in the Contiki collect program; reduction in power consumption for the X-MAC radio mechanism; performance improvements and bugfixes to the Coffee flash file system; workaround for a problem with the CC2420 radio.
One of the nice things with protothreads is that they can be implemented in pure ANSI C. But what if your C compiler does not adhere to the ANSI C standard? This is a problem for developers using the Microchip PIC platform, a microcontroller architecture notorious for its lack of ANSI C compilers. Fortunately, it is possible to overcome this problem by implementing a tailored version of the local continuation primitive. This is what Igor Lesik has done to get protothreads running on the PIC with the CCS compiler.
Written by Adam Dunkels,
Wednesday, 20 August 2008
Christopher Wang is developing an open source ZigBee stack based on Contiki. He also maintains a great newsfeed of interesting news from the wireless industry. See his website for his development blog and and newsfeed!
Ben Hoyt over at microBlog have written a piece on protothreads in C++. From the post: "What protothreads give you is the ability to write procedural, thread-style code, but without the overhead of real threads. The kind of thing embedded programmers normally use switch state machines for." He has implemented protothreads as a C++ class that is easy to use: take a look at the nice examples.
With protothreads in C++, protothread-local state is easily kept in instance variables instead of stack local variables and there is no need to explicitly store the state across blocking wait statements.
The existing tutorial on how to install Contiki 2.2 along with the MSP430 tools and a Tmote Sky / TelosB development environment for the Intel-based Mac is a little old by now. Andrew Pullin from UC Berkeley have contributed a new tutorial, complete with an installer! Read on for details.
One of the new features in Contiki 2.2 is the Contiki-collect program that collects sensor data from a network of Tmote Sky or TelosB boards running Contiki. Contiki-collect is a small Java program that interacts with the Contiki shell to retreive temperature, humidity, light, and power profile readings from the nodes and displays the data graphically. The system can also upload a Contiki system image to all connected Tmote Sky / TelosB boards. Watch the video for full details.
The Contiki project is happy to announce the release of version 2.2 of the Contiki operating system! Contiki 2.2 brings a set of new features: the shell has been much improved and now supports network-level commands, low-power radio networking, sensor data collection, and power profiling; Coffee, a new flash ROM-based file system; contiki-collect: a program for collecting and displaying sensor data from the network; a network time synchronization mechanism; the Chameleon architecture that separates protocol headers from protocol logic; the LPP experimental power-saving MAC protocol.
We are happy to announce the release of Contiki 2.2.1! The focus of this release is to fix bugs found in the 2.2 version. The changes are: significant bugfixes and performance improvements to the data collection protocol; improved data presentation in the Contiki collect program; reduction in power consumption for the X-MAC radio mechanism; performance improvements and bugfixes to the Coffee flash file system; workaround for a problem with the CC2420 radio.
