MICAz

MICAz is a mote from Crossbow Technology, MEMSIC. This mote uses an ATmega128L microcontroller and the CC2420 radio chip. ATmega128L is an 8-bit microcontroller from Atmel. This MCU has capabilities such as 128K of in-system, self-programmable flash program memory, 4K of EEPROM, and 4K of internal SRAM. You can explore this MCU by reading its datasheet at http://www.atmel.com/images/doc2467.pdf .

On the radio side, this mote uses a CC2420 chip that implements IEEE 802.15.4 protocol. This chip has energy-saving capabilities. You can work in sleep mode on a network layer stack. You can read more information about MICAz at http://www.memsic.com/wireless-sensor-networks/ . You can see a MICAz board form in Figure 1-5 (source: http://www.memsic.com/wireless-sensor-networks/ ).

Mica2

Mica2 is similar to the MICAz mote in that the mote uses an Atmel ATmega128L microcontroller; it uses the CC1000 radio chip for the wireless module. The battery connector is also provided to work standalone. You can see the Mica2 mote in Figure 1-6 (source: http://www.snm.ethz.ch/snmwiki/pub/uploads/Projects/mica2.jpg ). To develop a program for this mote, you should use a development board to flash the program.

TelosB

TelosB is the famous model that researchers and makers use for TinyOS implementation. This mote also can be used for the Contiki platform. TelosB motes use an MSP430 microcontroller from Texas Instruments (TI). The MSP340 series in TelosB are built from MSP430x15x, MSP430x16x, and MSP430x161x. Many manufacturers build WSN motes based on the TelosB design. You can see a TelosB mote in Figure 1-7 (source: https://www.advanticsys.com/shop/mtmcm5000msp-p-14.html ).

Iris

Iris is a WSN mote from Crossbow. It’s built from an ATmega1281 microcontroller and the Atmel AT86RF230 radio chip. Atmel ATmega1281 has a flash memory that is about 128K and 8K of RAM so you can write programs in more spaces. You can see Iris mote in this site, http://www.memsic.com/wireless-sensor-networks/ . In Figure 1-8, you can see my Iris mote from Crossbow, which is connected to my notebook.

Custom TinyOS Motes

Independent makers or manufacturers can build their own TinyOS motes, including sensors with specific purposes. The scheme and layout of the TinyOS mote have already been shared so it’s not difficult to build your own.

BTnode is a mote based on TinyOS and uses an Atmel ATmega 128K MCU and Chipcon CC1000 radio module. This mote was developed by ETH Zurich. Currently, they have released BTnode revision 3. You can see it in Figure 1-9. Further information about BTnode can be found at http://www.btnode.ethz.ch/ .

For more information, you can get a list of compatible TinyOS and Contiki motes at https://en.wikipedia.org/wiki/List_of_wireless_sensor_nodes . You can review some WSN motes for your own development.

Z1 Platform

The Z1 platform is a general-purpose development platform for WSN. This board uses an MSP430F2617 low-power microcontroller. The Z1 platform radio modules use a CC2420 transceiver and are IEEE 802.15.4 compliant, which operates at 2.4GHz with an effective data rate of 250Kbps. For further information, you can visit https://zolertia.io/ . You can see a form of Z1 platform in Figure 1-10.

Contiki-NG ARM-based Boards

In this book, I use five board models: Telosb, TI CC2650 LaunchPad, TI CC2650 Sensortag, TI CC1350 LaunchPad, and TI CC1350 Sensortag.

Instant Contiki

Contiki provides a complete development environment under Ubuntu Linux that is available in virtual-machine form. This approach is easy and low risk without breaking your current OS.

VMWare Workstation Player is free. It is available for Windows and Linux. For Mac users, there is no free VMWare Workstation Player. You can use VMWare Fusion. I have installed VMWare Workstation Player on Windows 10. You can see it in Figure 1-12.

Now, you can open Instant Contiki using VMWare Workstation Player by clicking Open a Virtual Machine. Navigate to the *.vmdk file in the folder to which Instant Contiki file was extracted.

After this succeeds, you can see Instant Contiki on VMWare Workstation Player, as shown in Figure 1-13.

By default, Instant Contiki is configured to use 1GB RAM. You can customize this by clicking Edit virtual machine settings. You should get a dialog as shown in Figure 1-14.

Since my computer has 16GB of RAM, I set my Instant Contiki with 4GB of RAM. If you are done, click the OK button to save and close the dialog.

Now, you can run Instant Contiki by clicking Play virtual machine; you should see the Ubuntu desktop. You can see it in Figure 1-15.

If your WSN mote has an MSP430-based MCU such as Sky and Telosb, you should install the ggc-msp430 library in order to develop your Contiki application. You can type this command in Ubuntu Terminal:

Your virtual machine is ready for Contiki development.

Manual Installation

If you have a computer with installed Linux, you can install the Contiki development environment on your platform.

First, you should install all required libraries to run Contiki OS. You can type these commands in Terminal:

You also need the Java run-time and SDK to run the Contiki OS simulator. In this case, we use Open JDK. You can use Java from Oracle. Type this command:

Since Contiki OS runs a 32-bit environment, if you have Linux OS with 64-bit, you can install these libraries:

Now, you can download the Contiki OS source code. Open Terminal and navigate to the specific folder where Contiki OS files will be extracted:

Your computer is ready for Contiki OS development.

Set Up Contiki-NG Development Environment

Currently, Contiki-NG does not provide an Instant Contiki, so it must be installed manually. The installation process can be found here: https://github.com/contiki-ng/contiki-ng/wiki/Toolchain-installation .

The first step to deploy Contiki-NG is to install all required libraries for development. In this section, I use Ubuntu Linux for development testing. I use Ubuntu LTS 16.04 with x64 platform. Type these commands on Linux Terminal to install libraries:

While you are installing Wireshark, you should enable the feature that allows non-superuser capture packets (select “yes”). Add your account into the wireshark group. You can type this command, substituting <user> with your Linux account:

The next step is to install the compiler and its dependencies, based on the Contiki mote hardware. If you have a Contiki mote based on MSP430, you can install the compiler and libraries for MSP430. You can type this command:

If you want to install the latest version of the MSP430 compiler, you can read how at https://github.com/tecip-nes/contiki-tres/wiki/Building-the-latest-version-of-mspgcc .

For Contiki mote–based ARMs such as CC2538DK and Zoul, you can install the ARM compiler by typing these commands:

We also install JDK and Ant for the Contiki simulator, COOJA, that are built from Java. You can install these libraries by typing this command:

If you have several Java versions within Linux, you should set your Java preference. It is done by calling update-alternatives:

Cooja needs to have the environment variable JAVA_HOME set to work with native Contiki motes. You should set JAVA_HOME with the path found above in the .profile file:

Most Contiki motes are attached to the computer via USB. When we access them, we probably need administrator privileges. To be able to access the USB without using the administrator level, your account should be part of the groups plugdev and dialout. You add them by typing these commands. Be sure to change <user> to your Linux account:

This is the case for an x64 platform. You probably will get an error when connecting via serial communication on a serial tool from Contiki-NG. You can install the following required libraries:

After finishing all tasks, you can reboot your computer.

Now, you can download Contiki-NG by cloning using git. Perform the following commands in Terminal:

Now, you are ready to develop Contiki-NG.

Explanation

This program declares a Contiki process thread, called hello_world_process. To print message to Terminal, use the printf() function:

hello_world_process will be executed automatically using AUTOSTART_PROCESSES().

AUTOSTART_PROCESSES(&hello_world_process);

Last, you should make a Makefile file. The following is the content of the Makefile file:

Change CONTIKI for your Contiki root folder where the Contiki source code files, https://github.com/contiki-os/contiki or https://github.com/contiki-ng/ for Contiki-NG, are located.

If all required program setup is done, we can compile C program using make by passing in the WSN platform. For our demo, we use the native app as the target, so we pass native while compiling:

This compiling generates a <project_name>.native binary file. You can see it in Figure 1-22. A hello-world.native file is generated.

To run the Contiki app, you can type this command:

If you get an error due to security issues, you probably need to run this program with administrator privilege. You can type this command:

It shows THE IPv6 address and displays “Hello, world” in Terminal. You can see it in Figure 1-23(a) for Contiki app and (b) for Contiki-NG app. To stop your Contiki program, you can press CTRL+C.

Next, we deploy the Contiki application to the Contiki hardware. For instance, I use TelosB as my WSN mote target. TelosB is a Sky platform from Contiki because TelosB uses MSP430 MCU.

Before deploying the Contiki program to the Contiki mote, make sure your Contiki mote is already attached to your computer. For instance, my Contiki mote, TelosB, is detected as /dev/ttyUSB0. You can verify the attached Contiki mote using the following command:

Now, you can compile and save the target platform by typing this command:

A sample of the compiling output is shown in Figure 1-24.

This compiling will generate a <project_name>.<platform> file. In my case, this will generate a hello-world.sky.ihex file:

If you get a permission error, you can run it using the administrator level:

This program will be flashed to Contiki hardware. It may take several minutes.

For Contiki-NG motes from Texas Instruments, you will probably get errors while uploading a program to the board. You can use SmartRF Flash Programmer. You can download it from http://www.ti.com/tool/FLASH-PROGRAMMER . Unfortunately, this tool currently only runs on Windows platforms.

To see the program output from the Contiki hardware, we listen to incoming messages from the serial port of the Contiki hardware. You can type this command:

You also can specify a serial port of the Contiki hardware. For instance, Contiki hardware on serial port /dev/ttyUSB0. You can type this command:

You can see the running Contiki program in Figure 1-25.

You may not get any message from the hello-world program. Since this program runs the first process, we may miss this process. Try to reset the Contiki hardware so Contiki OS will reboot. Then, run the program.

It displays “Hello, world” in the listening program. You can see it in Figure 1-26. To stop your Contiki listening program, you can press CTRL+C.

Setting Up

Before you run COOJA, you should configure your computer to update and check missing libraries for the COOJA application. Your computer should connect to the Internet.

You can configure COOJA by typing these commands:

If this succeeds, you can run the COOJA application by typing this command:

You should get the COOJA application, shown in Figure 1-28.

Running Contiki Application

After you launch the COOJA application, you can run the Contiki application using COOJA. First, create a new simulation on COOJA. You can click File ➤ New simulation. You can see it in Figure 1-29.

You should get the dialog shown in Figure 1-30. Fill in the simulation name. If done, click the Create button.

Now, you will get the Contiki simulator editor, COOJA, that is shown in Figure 1-31.

The next step is to add the WSN motes on the simulator. You can do it by clicking menu Motes ➤ Add motes ➤ Mote platform (see Figure 1-32). Please select your Mote platform preference. For demo, I use Sky platform.

Then, you will get the dialog shown in Figure 1-33. In the Contiki process/Firmware field, select your Contiki program. For demo purposes, we use the hello-world application. Select the hello-world.c file.

Compile the Contiki program by clicking the Compile button. You can see the sample of compilation output in Figure 1-34.

After compiling has completed, you will be asked to enter a number of WSN motes with their positions. For demo purposes, I fill in one WSN mote, as in Figure 1-35.

If done, click the Add motes button.

Now you can see your motes in the network map. For instance, you can see my WSN mote in Figure 1-36.

To run the simulation, you can click the Start button on the Simulation Control dialog. See it in Figure 1-37.

After the Start button has been clicked, the Contiki program will run on COOJA. You should see the message “Hello, world” on the output panel. You can see it in Figure 1-38.

Hardware Debugger

Most WSN motes do not provide built-in hardware debuggers, so if you want to debug a Contiki-NG program through the hardware approach, you need additional hardware. Regarding what WSN mote model you want to perform debugging on, you should check your MCU model.

For Atmel MCU on MICAz, Mica2, and Iris platforms, you need JTAG Atmel. Otherwise, for MCU-based MSP430, you use MSP430 USB Debugging Interface from Texas Instruments (TI). This tool is shown in Figure 1-39 (source: http://www.ti.com/tool/msp-fet ). You can buy it on this site: http://www.ti.com/tool/msp-fet .

Hardware debuggers usually have capabilities in a remote debugger. For professional purposes, I recommend you use this tool.

LED Indicators

In general, a WSN mote is equipped with several LEDs. We can use these LEDs to indicate a specific task; for instance, we turn on a specific LED to inform us that the WSN mote performs sensing. You can find an LED library in the <contiki>/core/dev/leds.h header file. In the next chapter, we will try to develop a Contiki application utilizing GPIO (General Purpose Input/Output).

Based on my experience, this approach is easy to implement. The downside of this method is having no more information; for instance, you might want to get a certain value from a specific task on your program.

Debugging Using Contiki Simulator

With the third approach, you can use the Contiki simulator, COOJA. You can compile and attach a Contiki program to the Contiki simulator. You can see messages that are generated using the printf() method. For instance, the hello-world application prints messages using printf().

The Contiki printf( ) Function

The last method that I like is using the printf() function. The idea is that our program writes messages using printf(), and then the messages will pass through to the serial port. To listen to incoming messages from the serial port, we can use the login command on Terminal.

This approach is easy and low cost for debugging your Contiki application. Just place a printf() function on the code you are investigating.