ESP Series Microcontrollers

// Simple WiFi Web Server Example
#include <ESP8266WiFi.h>

const char* ssid = "YourSSID";
const char* password = "YourPassword";

WiFiServer server(80);

void setup() {
  Serial.begin(115200);
  WiFi.begin(ssid, password);
  
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  
  server.begin();
}

void loop() {
  WiFiClient client = server.available();
  if (client) {
    client.println("HTTP/1.1 200 OK");
    client.println("Hello from NodeMCU!");
    client.stop();
  }
}

// Run task on Core 0
xTaskCreatePinnedToCore(
    Task1,    // Task function
    "Task1",  // Name
    10000,    // Stack size
    NULL,     // Parameters
    1,        // Priority
    NULL,     // Task handle
    0         // Core 0
);

void Task1(void * pvParameters) {
    while(1) {
        // Your code here
        vTaskDelay(1000);
    }
}

// Simple BLE Server Example
#include <BLEDevice.h>

BLEServer *pServer;
BLEService *pService;
BLECharacteristic *pCharacteristic;

void setup() {
  BLEDevice::init("ESP32_BLE");
  pServer = BLEDevice::createServer();
  pService = pServer->createService("1234");
  
  pCharacteristic = pService->createCharacteristic(
    "ABCD",
    BLECharacteristic::PROPERTY_READ |
    BLECharacteristic::PROPERTY_WRITE
  );
  
  pCharacteristic->setValue("Hello World");
  pService->start();
  pServer->getAdvertising()->start();
}

// Deep Sleep Example
#include <esp_sleep.h>

void setup() {
  esp_sleep_enable_timer_wakeup(1000000 * 60); // 1 minute
  esp_deep_sleep_start();
}

void loop() {} // Never reached

// ESP-NOW Example
#include <esp_now.h>

void OnDataSent(const uint8_t *mac_addr, esp_now_send_status_t status) {
  Serial.println(status == ESP_NOW_SEND_SUCCESS ? 
    "Delivery Success" : "Delivery Fail");
}

void setup() {
  WiFi.mode(WIFI_STA);
  if (esp_now_init() != ESP_OK) {
    Serial.println("ESP-NOW Init Failed");
    return;
  }
  
  esp_now_register_send_cb(OnDataSent);
  
  esp_now_peer_info_t peerInfo;
  memcpy(peerInfo.peer_addr, broadcastAddress, 6);
  peerInfo.channel = 0;
  peerInfo.encrypt = false;
  
  esp_now_add_peer(&peerInfo);
}