Example Codes

Sender Node

Below is an example code of a node which broadcasts a message to every other node in the mesh network every 10 seconds. A sender node usually behaves as child nodes.

#include <painlessMesh.h>

// Mesh network parameters
#define MESH_PREFIX     "yourMeshNetwork"
#define MESH_PASSWORD   "yourMeshPassword"
#define MESH_PORT       5555

painlessMesh mesh;

// FreeRTOS Task Handle for mesh updates
TaskHandle_t meshUpdateTaskHandle;

// Function to handle received messages
void receivedCallback(uint32_t from, String &msg) {
    Serial.printf("Received message from node %u: %s\n", from, msg.c_str());
}

// Task to continuously update the mesh network
void meshUpdateTask(void *pvParameters) {
    while (true) {
        mesh.update();
        vTaskDelay(10 / portTICK_PERIOD_MS);  // Short delay to yield to other tasks
    }
}

void setup() {
    Serial.begin(115200);

    // Initialize mesh network
    mesh.setDebugMsgTypes(ERROR | STARTUP | CONNECTION);  // Debug message types
    mesh.init(MESH_PREFIX, MESH_PASSWORD, MESH_PORT);
    mesh.onReceive(&receivedCallback);  // Register the message receive callback

    // Create FreeRTOS task for updating mesh
    xTaskCreate(
        meshUpdateTask,             // Function to implement the task
        "MeshUpdateTask",            // Task name
        8192,                        // Stack size
        NULL,                        // Task input parameter
        1,                           // Priority
        &meshUpdateTaskHandle       // Task handle
    );
}

void loop() {
    
}

Receiver Node

Below is an example code of a node which receives messages from every other node in the mesh network that are within range. A receiver node usually behaves as parent nodes.

#include <painlessMesh.h>

// Mesh network parameters
#define MESH_PREFIX     "yourMeshNetwork"
#define MESH_PASSWORD   "yourMeshPassword"
#define MESH_PORT       5555

painlessMesh mesh;

// FreeRTOS Task Handle for mesh updates
TaskHandle_t meshUpdateTaskHandle;

// Function to handle received messages
void receivedCallback(uint32_t from, String &msg) {
    Serial.printf("Received message from node %u: %s\n", from, msg.c_str());
}

// Task to continuously update the mesh network
void meshUpdateTask(void *pvParameters) {
    while (true) {
        mesh.update();
        vTaskDelay(10 / portTICK_PERIOD_MS);  // Short delay to yield to other tasks
    }
}

void setup() {
    Serial.begin(115200);

    // Initialize mesh network
    mesh.setDebugMsgTypes(ERROR | STARTUP | CONNECTION);  // Debug message types
    mesh.init(MESH_PREFIX, MESH_PASSWORD, MESH_PORT);
    mesh.onReceive(&receivedCallback);  // Register the message receive callback

    // Create FreeRTOS task for updating mesh
    xTaskCreate(
        meshUpdateTask,             // Function to implement the task
        "MeshUpdateTask",            // Task name
        8192,                        // Stack size
        NULL,                        // Task input parameter
        1,                           // Priority
        &meshUpdateTaskHandle       // Task handle
    );
}

void loop() {
    
}