Thread Interface

Overview

This section outlines the development of the Thread Interface component, which provides the features and functions to create Thread networks and commission devices to join them.

This component is part of the Orchestrator firmware.

Pre-requisites:

The steps in Project Bootstrap section are completed.
System Initialization is completed.

Development

Step 1: Create Component

The command below creates a new component named thread_interface inside the components directory.

idf.py create-component thread_interface -C components

The CONFIG_OPENTHREAD_ENABLE configuration option has to be set to y in the sdkconfig.defaults file in order to enable the OpenThread component.

Step 2: Change Source File Extension

Change the file extension of the thread_interface.c file to thread_interface.cpp.

mv components/thread_interface/thread_interface.c components/thread_interface/thread_interface.cpp

Step 3: Manage Thread Network

The thread_interface.h file declares functions for managing the Thread network:

Initializing the Thread Interface
The initialization process involves the following steps:
1. Configure event handlers to manage Thread network events.
2. Set up the Event VFS, a lightweight mechanism that represents events as file descriptors, similar to Linux's eventfd. This allows tasks to signal and wait for events. The Event VFS is part of the broader VFS component, which provides a unified interface for various file systems.
3. Creating a Dedicated FreeRTOS Task, declared in thread_task.h, using the xTaskCreate function. This task:
  - Initializes a new OpenThread network interface using esp_netif.
  - Initializes the OpenThread stack and attaches the network interface.
  - Sets up the OpenThread CLI
  - Starts OpenThread.
Shutting Down the Thread Interface
- Stops the OpenThread stack.
- Deletes the OpenThread task using vTaskDelete.
- Unregisters the Event VFS.
- Cleans up allocated semaphores and network interfaces.
Retrieving and Setting the Operational Dataset
Getting the Device’s Thread Role:
- Disabled – The device is not participating in the Thread network.
- Detached – The device is trying to connect to a Thread network but is not yet attached.
- Child – The device is connected to a Thread network but does not route traffic.
- Router – The device is forwarding messages for other Thread nodes.
- Leader – The device is managing the Thread network and ensuring proper operation.

OpenThread Configuration

Create a file that defines default configurations for OpenThread on ESP32-C6:

touch esp_ot_config_esp32c6.h

The code below sets up the network interface for Thread communication and configures the radio to use native mode. It also manages storage and task queues through the port configuration.

#pragma once #include "esp_openthread_types.h" #include <driver/uart.h> #include <driver/gpio.h> #include <esp_netif.h> #ifdef __cplusplus extern "C" { #endif // ----------------------------------------------------------------------------- // Network Interface Configuration for OpenThread // ----------------------------------------------------------------------------- #define OT_NETIF_INHERENT_CONFIG() { \ .flags = (esp_netif_flags_t)0, \ .mac = { 0 }, \ .ip_info = { 0 }, \ .get_ip_event = 0, \ .lost_ip_event = 0, \ .if_key = "OT_DEF", \ .if_desc = "THREAD_NETIF", \ .route_prio = 15 \ } /* Declare a static inherent configuration instance */ static const esp_netif_inherent_config_t ot_netif_inherent_config_instance = OT_NETIF_INHERENT_CONFIG(); #define OT_NETIF_CONFIG() { \ .base = &ot_netif_inherent_config_instance, \ .stack = &g_esp_netif_netstack_default_openthread \ } // ----------------------------------------------------------------------------- // OpenThread Radio Default Configuration // ----------------------------------------------------------------------------- #define ESP_OPENTHREAD_DEFAULT_RADIO_CONFIG() \ { \ .radio_mode = RADIO_MODE_NATIVE \ } // ----------------------------------------------------------------------------- // OpenThread Host Default Configuration // ----------------------------------------------------------------------------- #if CONFIG_OPENTHREAD_CONSOLE_TYPE_UART #define ESP_OPENTHREAD_DEFAULT_HOST_CONFIG() \ { \ .host_connection_mode = HOST_CONNECTION_MODE_NONE, \ } #elif CONFIG_OPENTHREAD_CONSOLE_TYPE_USB_SERIAL_JTAG #define ESP_OPENTHREAD_DEFAULT_HOST_CONFIG() \ { \ .host_connection_mode = HOST_CONNECTION_MODE_CLI_USB, \ .host_usb_config = USB_SERIAL_JTAG_DRIVER_CONFIG_DEFAULT() \ } #endif // ----------------------------------------------------------------------------- // OpenThread Port Default Configuration // ----------------------------------------------------------------------------- #define ESP_OPENTHREAD_DEFAULT_PORT_CONFIG() \ { \ .storage_partition_name = "nvs", \ .netif_queue_size = 10, \ .task_queue_size = 10 \ } // ----------------------------------------------------------------------------- // OpenThread Default Configuration // ----------------------------------------------------------------------------- #define ESP_OPENTHREAD_DEFAULT_CONFIG() \ { \ .radio_config = ESP_OPENTHREAD_DEFAULT_RADIO_CONFIG(), \ .host_config = ESP_OPENTHREAD_DEFAULT_HOST_CONFIG(), \ .port_config = ESP_OPENTHREAD_DEFAULT_PORT_CONFIG() \ } #ifdef __cplusplus } #endif

References

OpenThread SDK:

How to Write an OpenThread Application

Android SDK

Last modified: 24 March 2025