ChibiOS on my cc2520+stm32f4 boards

I have created a simple example where I use ChibiOS on my rf boards. You can download it here:


In order to build it, you need ChibiOS with the ST libraries in the ext directory, which you can download here:


Update: The ST libraries are no longer required, but you can still use the ChibiOS-version above if you’d like. It should work just as well with the official version.

In this example, there are two threads that send and receive RF packets between two RF boards. If this program is uploaded to two RF boards, the red LED on each board should blink because the other board sends packets to switch it on and off and vice versa. The green LED is on as long as the board receives acks from the other board. Auto-ack can also be switched off – then the green LED should be on all the time.

This example also emulates an USB modem when the USB cable is plugged in, so you can use you favourite serial terminal to connect to it. The baudrate is ignored and does not matter. On Ubuntu, it will show up as something like /dev/ttyACM0 (or 1 or n) depending on whether you have other USB modems.

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A Contiki port for my custom cc2520+stm32f4-boards

Previously, I have designed a small circuit board with a cc2520 rf-tranceiver and a stm32f4 microcontroller (see this post). After porting the driver for the cc2520 to ChibiOS for a few tests, I decided to port Contiki to support this platform as well. As this is the first time that I work with Contiki, uipv6 and 6LoWPAN, this was quite a challenge for me. Nevertheless, I managed to make the following features work:

  • The cc2520 radio
  • The RPL border router using the USB connector
  • RIME
  • IPv6
  • LEDs
  • printf for debugging
  • Many applications, such as the webserver, telnet, udp
  • I made a driver for ws2811 LEDs that uses DMA and a timer

In this post, I will describe what the essential steps were to port Contiki to this board and how to use my port. I have uploaded the Contiki port together with a few example applications to github. You can download it here.

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CC2520 and STM32 RF boards

I have made a small PCB with an STM32F4 microcontroller and a TI CC2520 radio transceiver. There are many mote modules available already, but I wanted one optimized for performance as opposed to power consumption. I also wanted to try making a PCB with some RF-parts since I haven’t done that before.

These are the 2-layer PCBs ordered from OSHPark:


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