How to Install Border Router on Esp32

In this codelab we will show you how to build and install an Open Thread Border Router on the esp32 development kits.

What You'll Build

In this codelab, you will:

Build and install the Open Thread Border Router on ESP32 development kits.
Learn about the concept of Matter Border Routers

Architecture

alt-architecture-here

In this CodeLab we will build the Open Thread Border Router (ot_br) on an ESP32 development kit. We will then build and install the Thread Radio Co-processor (ot_rcp) on the ESP32-H2. This will allow us to create a border router between a Wifi and Thread Network. In doing so, we will learn how Border Routers work in Matter.

What You'll Learn

What you will need (Pre-requisities)
How to set up the ESP32 and ESP32-H2 Thread Border Router
How to build and install the Open Thread radio co-processor
How to build and install the Open Thread Border Router
How to set up a Command Line Interface on a thread device
How to check commmunication between a Thread and a Wifi/IP Network
Where you can get more information of the ESP32 Open Thread Border Router

This set of Codelabs will use Ubuntu 22.04 on a Amd64 based architecture. If you are using Mac OS then you should follow the instructions directly from the Matter repo

You will need

an ESP32 develoment kit. We will use an ESP32_DEVKITC_V4.
an ESP32-H2 develoment kit to add support for Thread
an ESP32-C6 develoment kit to use as a Thread CLI device.
a laptop or PC running Ubuntu 22.04
Visual Studio Code IDE
a basic knowledge of Linux shell commands

The total codelab will take approximately a Duration of 30 minuates to complete.

We will be using the OpenThread Border Router Example application which is available on the Espressif ESP-IDF github repo for ot_br

First thing to do is sonnect the two SoCs via UART, below is an example setup with ESP32 DevKitC and ESP32-H2 DevKitC:

wiring diagram

The pin outs are as follows:

ESP32 pin	ESP32-H2 pin
GND	G
GPIO4	TX
GPIO5	RX

Note: Once you have built this circuit I would suggest to disconnect the TX pin from the ESP32. I have found that leaving this connected prevents the flashing of the ESP32-H2 board.

We will be using the OpenThread Radio CoProcessor Example application which is available on the Espressif ESP-IDF github repo for ot_rcp

To run this example, a board with IEEE 802.15.4 module (for example ESP32-H2) is required. We will use the ESP32-H2.

First plug in your ESP32-H2 (using the UART not JTAG port) and check which port the board is available on

ls /dev/ttyUSB*

Make note of this device.

Then, temporarily, disconnect the TX pin from the ESP32. I have found that leaving this connected prevents the flashing of the ESP32-H2 board.
We need to initialize the esp-idf environment

cd ~/Projects/esp-idf #or where you located your esp-idf environment
source ./export.sh

We will then navigate to the Espressif Open Thread Radio Co-Processor example.

cd examples/openthread/ot_rcp

Set the esp target to be the esp32h2

idf.py set-target esp32h2

Build the ot_br example for the esp32-h2

idf.py build

If everything worked OK you should see an Executable Linkable Format file called esp_ot_rcp.elf in the build directory

Note: if you run into any difficulties in can be useful to clean up the temporary build folder using rm -rf build as this can often solve some build issues.

Adding User to dialout or uucp on Linux The currently logged user should have read and write access the serial port over USB. On most Linux distributions, this is done by adding the user to dialout group with the following command:

sudo usermod -a -G dialout $USER

Finally, you will then flash the image on to the ESP32-H2. But its good practice to erase the flash before hand

idf.py -p /dev/ttyUSB0 erase_flash # replace the ttyUSB0 with the correct USB device from above
idf.py -p /dev/ttyUSB0 flash monitor

Finally, reconnect the TX pin from the ESP32. This is important.

We will be using the OpenThread Border Router Example application which is available on the Espressif ESP-IDF github repo for ot_br

To run this example, an ESP32 series Wi-Fi SoC (ESP32, ESP32-C, ESP32-S, etc) is required. In this case, we will use an ESP32 development kit v4.

First plug in your ESP32 and check which port the board is available on

ls /dev/ttyUSB*

Make note of this device.

Note: if you have not already created the environment for connectedhomeip and esp-idf install then follow the steps on the previous page.

We will then navigate to the Espressif Open Thread Border Router example

cd ~/Projects/esp-idf #or where you located your esp-idf environment
cd examples/openthread/ot_br

Set the esp target to be the esp32

idf.py set-target esp32

Build the ot_br example for the esp32

idf.py build

If everything worked OK you should see an Executable Linkable Format file called esp_ot_br.elf in the build directory

Note: if you run into any difficulties in can be useful to clean up the temporary build folder using rm -rf build as this can often solve some build issues.

Finally, you will then flash the image on to the ESP32-H2. But its good practice to erase the flash before hand

idf.py -p /dev/ttyUSB1 erase_flash # replace the ttyUSB1 with the correct USB device from above
idf.py -p /dev/ttyUSB1 flash monitor

We will be using the OpenThread CLI Example application which is available on the Espressif ESP-IDF github repo for ot_cli

To run this example, an ESP32 series Wi-Fi SoC (ESP32, ESP32-C, ESP32-S, etc) is required. In this case, we will use a ESP32-C6.

First plug in your ESP32-C6 and check which port the board is available on

ls /dev/ttyUSB*

Make note of this device.

Note: if you have not already created the environment for connectedhomeip and esp-idf install then follow the steps on the previous page.

We will then navigate to the Espressif Open Thread CLI example

cd ~/Projects/esp-idf #or where you located your esp-idf environment
cd examples/openthread/ot_cli

Set the esp target to be the esp32-c6

idf.py set-target esp32-c6

Build the ot_cli example for the esp32

idf.py build

If everything worked OK you should see an Executable Linkable Format file called esp_ot_cli.elf in the build directory

Note: if you run into any difficulties in can be useful to clean up the temporary build folder using rm -rf build as this can often solve some build issues.

Finally, you will then flash the image on to the ESP32-H2. But its good practice to erase the flash before hand

idf.py -p /dev/ttyUSB2 erase_flash # replace the ttyUSB2 with the correct USB device from above
idf.py -p /dev/ttyUSB2 flash monitor

In this section of the codelab, we will check that we can communicate between our Thread network and the external IP network. Specifically, we will try to ping the Google DNS servers (which are on the public Internet)

In the terminal that is running the CLI example, run the following commands

factoryreset # the device will reboot

Set up the Thread network by running the following commands:

> dataset init new
Done
> dataset commit active
Done
> ifconfig up
Done
> thread start
Done

If everything has gone ok you should be able to see that this thread device has become a leader. This may take a few seconds.

> state
leader
Done

Now the first device has formed a Thread network as a leader. Get some information which will be used in next steps.

> ipaddr
fdde:ad00:beef:0:0:ff:fe00:fc00
fdde:ad00:beef:0:0:ff:fe00:8000
fdde:ad00:beef:0:a7c6:6311:9c8c:271b
fe80:0:0:0:5c27:a723:7115:c8f8

# Get the Active Dataset
> dataset active -x
0e080000000000010000000300001835060004001fffe00208fe7bb701f5f1125d0708fd75cbde7c6647bd0510b3914792d44f45b6c7d76eb9306eec94030f4f70656e5468726561642d35383332010258320410e35c581af5029b054fc904a24c2b27700c0402a0fff8

We will now join the OT Border Router to our Wifi network.

On the Terminal running the OT_BR example type the following command to join the OT border router to the Wifi Network

wifi connect -s myssid -p mypassword

If everything worked OK you should be able to see that the wifi is connected by using:

> wifi state
connected
Done

We will then join the OT Border Router to our Thread network.

On the Terminal running the OT_BR example type the following command to join the OT border router to the Thread Network

> dataset set active 0e080000000000010000000300001835060004001fffe00208fe7bb701f5f1125d0708fd75cbde7c6647bd0510b3914792d44f45b6c7d76eb9306eec94030f4f70656e5468726561642d35383332010258320410e35c581af5029b054fc904a24c2b27700c0402a0fff8
> ifconfig up
Done
> thread start
Done

If everything worked OK you should be able to see that the border router is now a router (or child) on the Thread network:

> state
router  # child is also a valid state
Done

Checking Communication between the Thread network and the IP network

In order to do a simple check between the Thread network and the IP network we will ping the Google DNS servers (i.e. 8.8.8.8 or 8.8.4.4) from the Thread device

On the Thread CLI device run the following command:

> ping 8.8.8.8

If everything worked successfully, you should see a response from the Google DNS servers thereby indicating that Thread network traffic has traversed the Border Router into the Wifi network and onwards to the external Internet.

Checkout the official documentation here: Espressif OpenThread Examples