Raspberry Pi 3B+ 802.15.4/6LoWPAN Setup

Summary

Information on how to setup a Raspberry Pi 3B+ for 802.15.4 radio/6LoWPAN communication by utilizing an Openlabs 802.15.4 radio module.

This was tested successfully with Raspbian 10 (Buster) and Raspbian 11 (Bullseye). I assume it is also working on the latest Raspbian 12 (Bookworm).

Requirements

• Raspberry Pi 3B+
• Operating system: Raspberry Pi OS (Raspbian)
• Openlabs 802.15.4 radio module: https://openlabs.co/store/Raspberry-Pi-802.15.4-radio
• Optional/alternatively (not tested yet): Raspberry Pi 6LoWPAN SLIP radio module

Setup/Config 802.15.4/6LoWPAN on a Raspberry

Install Raspbian on Raspberry Pi 3B+

• Use Raspberry Pi Imager
• Optional: Download Raspbian/Raspberry Pi OS from https://www.raspberrypi.com/software/operating-systems/

Preparation of Raspbian

Access the Raspberry Pi by attaching it via HDMI to a monitor. After enabling SSH it is possible to connect via SSH/terminal (default credentials are pi:raspberry).

• (Optionally) Change keyboard setting to "German" and reboot:

sudo dpkg-reconfigure keyboard-configuration

• Activate and start SSH on Raspberry:

sudo systemctl start ssh
sudo systemctl enable ssh

• Upgrade of Raspbian:

sudo apt update && sudo apt upgrade

Enable support for IEEE 802.15.4/LoWPAN devices

• Plug the OpenLabs 802.15.4 radio module directly onto pins 15-26 of the Raspberry's P1 header (in the middle):

• There is an existing overlay for this transceiver shipped with Raspbian, should be in /boot/overlays/at86rf233-overlay.dtb or /boot/overlays/at86rf233.dtbo:

ls /boot/overlays/at86rf233.dtbo

• Enable transceiver by modifying the /boot/config.txt file and reboot:

sudo nano /boot/config.txt
# enable OpenLabs 802.15.4 radio module
dtoverlay=at86rf233, speed=3000000

Installation of Linux WPAN tools

Sources/Links: see References:#Linux WPAN tools

• First install git and clone the wpan-tools Repository:

sudo apt install git
sudo mkdir /opt/src
sudo chown pi /opt/src
cd /opt/src
git clone https://github.com/linux-wpan/wpan-tools

• Install some required packages before building the wpan-tools:

sudo apt install dh-autoreconf libnl-3-dev libnl-genl-3-dev

• Configure, build and install wpan-tools:

cd /opt/src/wpan-tools
./autogen.sh
./configure CFLAGS='-g -O0' --prefix=/usr --sysconfdir=/etc --libdir=/usr/lib
make
sudo make install

• Verification/test of wpan-tools installation:

iwpan dev

MANUAL WPAN interface configuration

Sources/Links: see References:#WPAN interface configuration

• Configure the default PAN ID of RIOT-OS/SAMR21-xpro: 0x23
• Configure the default channel ID of RIOT-OS/SAMR21-xpro: 26

ip link set lowpan0 down
ip link set wpan0 down
iwpan phy phy0 set channel 0 26 # same network ID and channel as RIOT default
iwpan dev wpan0 set pan_id 0x23 # same network ID and channel as RIOT default
ip link add link wpan0 name lowpan0 type lowpan
ip link set wpan0 up
ip link set lowpan0 up

• Afterwards the lowpan0 interface on Raspberry has a link-local IPv6 address:

root@raspberrypi:~# ip a
1: lo: [...]
2: eth0: [...]
3: wlan0: [...]
4: wpan0: <BROADCAST,NOARP,UP,LOWER_UP> mtu 123 qdisc pfifo_fast state UNKNOWN group default qlen 300
   link/ieee802.15.4 36:3a:07:cc:65:41:2b:31 brd ff:ff:ff:ff:ff:ff:ff:ff
5: lowpan0@wpan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1280 qdisc noqueue state UNKNOWN group default qlen 1000
   link/6lowpan 36:3a:07:cc:65:41:2b:31 brd ff:ff:ff:ff:ff:ff:ff:ff
   inet6 fe80::343a:7cc:6541:2b31/64 scope link
      valid_lft forever preferred_lft forever

NOTE/CAUTION: Every reboot changes the link-local IPv6 address of the lowpan0 interface on the Raspberry!

See #PERSISTENT wpan0 and lowpan0 configuration to configure a persistent link-local address.

There are also scripts available to create/delete a lowpan interface (or to create/delete a monitor interface): https://github.com/RIOT-Makers/wpan-raspbian

PERSISTENT wpan0 and lowpan0 configuration

With static long hardware address and static link-local IPv6 address (to avoid a random link-local IPv6 address on each reboot).

Sources/Links: see References:#Persistent WPAN interface configuration

• Clone riot-makers/wpan-raspbian GitHub repo:

cd /opt/src
git clone https://github.com/riot-makers/wpan-raspbian
cd wpan-raspbian

• Copy some helper (shell) scripts to a well-known location:

sudo cp -r usr/local/sbin/* /usr/local/sbin/.
sudo chmod +x /usr/local/sbin/*

• Afterwards copy files for systemd integration:

sudo cp etc/default/lowpan /etc/default/.
sudo cp etc/systemd/system/lowpan.service /etc/systemd/system/.

• Modify 802.15.4 channel ID and PAN ID in /etc/default/lowpan as needed:

sudo nano /etc/default/lowpan
CHN="13"
PAN="0xbeef"
# set MAC to "" for random mac/hw address
MAC="02:0:0:0:0:0:0:1"
# set IPv6 to "" if not required; note: set a prefix length
#IP6="fdaa:bb:cc:dd::1/64"
# Set ACK requests (Only enable if all devices on your PAN support ACKs)
ACKREQ=0

Note: MAC="02:0:0:0:0:0:0:1" was taken from https://jan.newmarch.name/IoT/LinuxJournal/Routing/, this results in a link-local address of fe80::1 for the Raspberry.

• Enable lowpan.service autostart, start 6LoWPAN service and verification:

sudo systemctl enable lowpan.service
sudo systemctl start lowpan.service
ifconfig
lowpan0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1280
   inet6 fe80::1  prefixlen 64  scopeid 0x20<link>
   unspec 02-00-00-00-00-00-00-01-00-00-00-00-00-00-00-00  txqueuelen 1000  (UNSPEC)
   RX packets 0  bytes 0 (0.0 B)
   RX errors 0  dropped 0  overruns 0  frame 0
   TX packets 19  bytes 2114 (2.0 KiB)
   TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
wpan0: flags=195<UP,BROADCAST,RUNNING,NOARP>  mtu 123
       unspec 02-00-00-00-00-00-00-01-00-00-00-00-00-00-00-00  txqueuelen 300  (UNSPEC)
       RX packets 72  bytes 2016 (1.9 KiB)
       RX errors 0  dropped 0  overruns 0  frame 0
       TX packets 74  bytes 5320 (5.1 KiB)
       TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

Verification of 6LoWPAN connectivity between a Raspberry and a SAMR21-xpro

• Use RIOT's gnrc_networking example and build it for the SAMR21-xpro board, flash the firmware to the SAMR21-xpro and connect via pyterm:

cd RIOT/examples/gnrc_networking
make BOARD=samr21-xpro
make BOARD=samr21-xpro flash
make BOARD=samr21-xpro term

• Use ifconfig to determine the 802.15.4/6LoWPAN interface ID of SAMR21-xpro (7 in this case):

ifconfig
# Iface  7  HWaddr: 57:98  Channel: 26  Page: 0  NID: 0x23  PHY: O-QPSK
[...]
#           Long HWaddr: E2:F9:02:0F:36:26:A2:68
[...]
#           inet6 addr: fe80::e0f9:20f:3626:a268  scope: link  VAL

• Note: All ifconfig config options can be shown with ifconfig <interface id> set.

• RIOT-OS default 802.15.4 channel is 26 and default PAN ID 0x23. If you change them, make sure to change them in the SAMR21-xpro configuration aswell:
  • [optional] Change the channel to 13 and the PAN ID to 0xbeef (see RIOT-OS and IEEE 802.15.4 / 6LoWPAN for more information):

ifconfig 7 set pan_id 0xbeef
ifconfig 7 set channel 13

Ping test from Raspberry to SAMR21-xpro

• Multicast ping test through interface lowpan0 to group ff02::1 (all nodes in the link-local):

ping ff02::1%lowpan0        
PING ff02::1%lowpan0(ff02::1%lowpan0) 56 data bytes
64 bytes from fe80::1%lowpan0: icmp_seq=1 ttl=64 time=0.195 ms
64 bytes from fe80::e0f9:20f:3626:a268%lowpan0: icmp_seq=1 ttl=64 time=10.4 ms (DUP!)

• Unicast ping (change to link-local IPv6 address of your SAMR21-xpro):

ping fe80::e0f9:20f:3626:a268%lowpan0
ping fe80::e0f9:20f:3626:a268%lowpan0
PING fe80::e0f9:20f:3626:a268%lowpan0(fe80::e0f9:20f:3626:a268%lowpan0) 56 data bytes
64 bytes from fe80::e0f9:20f:3626:a268%lowpan0: icmp_seq=1 ttl=64 time=23.0 ms
[...]

Ping test from SAMR21-xpro to Raspberry

• Multicast ping test through interface 7 to group ff02::1:

# ping6 ff02::1%7
# 12 bytes from fe80::1%7: icmp_seq=0 ttl=64 rssi=-61 dBm time=8.309 ms
# 12 bytes from fe80::1%7: icmp_seq=1 ttl=64 rssi=-61 dBm time=6.124 ms
# 12 bytes from fe80::1%7: icmp_seq=2 ttl=64 rssi=-59 dBm time=6.461 ms
#
# --- ff02::1 PING statistics ---
# 3 packets transmitted, 3 packets received, 0% packet loss
# round-trip min/avg/max = 6.124/6.964/8.309 ms

• Unicast ping from SAMR21-xpro to Raspberry 6LoWPAN interface:

# ping6 fe80::1%7
# 12 bytes from fe80::1%7: icmp_seq=0 ttl=64 rssi=-61 dBm time=8.467 ms
# 12 bytes from fe80::1%7: icmp_seq=1 ttl=64 rssi=-61 dBm time=7.966 ms

Test CoAP communication between Raspberry and SAMR21-xpro

• Install python3-pip and aiocoap on Raspberry:

sudo apt install python3-pip
pip3 install --upgrade "aiocoap[all]"

• Clone aiocoap repo and start the included simple CoAP server:

git clone https://github.com/chrysn/aiocoap.git
cd aiocoap
python3 server.py

• Use gcoap example on SAMR21-xpro (RIOT-OS repo already cloned):

cd ~/RIOT/example/gcoap
make BOARD=samr21-xpro         //build gcoap example
make BOARD=samr21-xpro flash       //flah gcoap to samr21-xpro
make BOARD=samr21-xpro term     //start pyterm

• [optional] Reset SAMR21-xpro and change 6LoWPAN settings:

ifconfig 7 set pan_id 0xbeef
ifconfig 7 set channel 13

• Send a CoAP request to the CoAP server:

coap put [fe80::1%7] 5683 /send test

Possible Problems with 6LoWPAN, SAMR21-xpro and Raspberry Pi (with Openlabs 802.15.4 radio)

• 6LoWPAN: RIOT does not receive packets from Linux when short_addr is set #11033
  • GitHub issue: https://github.com/RIOT-OS/RIOT/issues/11033
  • By default this is not set (i.e. in RIOT gnrc_networking example!)
• Do not use Raspberry Pi 4 with OpenLabs 802.15.4 radio module:
  • At least with the newest available Kernel (i.e. 5.10 during our tests) it was only possible to send 802.15.4 packets to SAMR21-xpro and the Raspberry did not receive any packets from SAMR21-xpro.
  • It is better to use a Raspberry Pi 3B(+)
    • Successfully tested with Raspbian 9 (Stretch), Raspbian 10 (Buster) and Raspbian 11 (Bullseye)
• Monitoring 802.15.4/6LoWPAN traffic: Correct channel ID must be set (RIOT-OS default: 26)
• Communication SAMR21-xpro<->Raspberry: The same channel ID (RIOT-OS default: 26) and PAN ID need to be set (RIOT-OS default: 0x23)

Used Hardware

• Raspberry_Pi_3,_Model_B+,_WLAN,_BT
• Raspberry_Pi_802.15.4_radio_module https://openlabs.co/store/Raspberry-Pi-802.15.4-radio
• Optional/alternatively (not tested): Raspberry Pi 6LoWPAN SLIP radio module
• SAMR21-xpro:
  • Remote IoT-Lab Atmel SAM R21 Xplained Pro Evaluation Platform
  • Atmel_SAM_R21_Xplained_Pro

Courses

• IT-Security master's programme: Mobile and Embedded Security ILV

References

• Documentation was (mostly) created based on our CoMatrix project: https://comatrix.eu
• Wiki: Riot-OS Setup
• https://comatrix.eu/setup/raspberry_pi_setup/
• https://openlabs.co/store/Raspberry-Pi-802.15.4-radio
• Wiki: RIOT-OS and IEEE 802.15.4 / 6LoWPAN
• Linux WPAN Tools: https://github.com/linux-wpan/wpan-tools
• Python CoAP implementation/library: https://github.com/chrysn/aiocoap

Linux WPAN tools

• https://github.com/RIOT-OS/RIOT/wiki/How-to-install-6LoWPAN-Linux-Kernel-on-Raspberry-Pi
• https://github.com/RIOT-Makers/wpan-raspbian/wiki/Create-a-generic-Raspbian-image-with-6LoWPAN-support
• https://github.com/RIOT-Makers/wpan-raspbian/wiki/Spice-up-Raspbian-for-the-IoT

WPAN interface configuration

• https://linux-wpan.org/documentation.html
• https://www.linuxjournal.com/content/low-power-wireless-6lowpan-ieee802154-and-raspberry-pi
• http://morschi.com/2017/04/05/hands-on-riot-6lowpan/

Persistent WPAN interface configuration

• https://github.com/RIOT-Makers/wpan-raspbian/wiki/Spice-up-Raspbian-for-the-IoT
• https://github.com/RIOT-Makers/wpan-raspbian
• https://jan.newmarch.name/IoT/LinuxJournal/Routing/