2025最新教程：NodeMCU如何低成本接入阿里云MQTT？

#include
#include
// WiFi配置
const char* ssid = “Your_WiFi_SSID”;
const char* password = “Your_WiFi_Password”;
// 阿里云物联网平台配置
#define PRODUCT_KEY “Your_Product_Key
#define DEVICE_NAME “Your_Device_Name
#define DEVICE_SECRET “Your_Device_Secret
// MQTT服务器配置

#define MQTT_SERVER PRODUCT_KEY “.iot-as–shanghai.
#define MQTT_PORT 1883
// Topic配置
#define SUB_TOPIC “/” PRODUCT_KEY “/” DEVICE_NAME “/user/get
#define PUB_TOPIC “/” PRODUCT_KEY “/” DEVICE_NAME “/user/update
WiFiClient espClient;
PubSubClient client(espClient);
// 生成MQTT连接参数
String clientId = “”;
String username = “”;
String password_mqtt = “”;
// 时间戳和加密库
#include
#include
void setup {
Serial.begin(115200);
setup_wifi;
setup_mqtt;
// 设置LED引脚
pinMode(LED_BUILTIN, OUTPUT);
digitalWrite(LED_BUILTIN, HIGH); // LED off
void setup_wifi {
delay(10);
Serial.println;
Serial.print(“Connecting to “);
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status != WL_CONNECTED) {
delay(500);
Serial.print(“.”);
Serial.println(“”);
Serial.println(“WiFi connected”);
Serial.println(“IP address: “);
Serial.println(WiFi.localIP);
void setup_mqtt {
// 计算MQTT连接参数
calculateMqttParams;
client.setServer(MQTT_SERVER, MQTT_PORT);
client.setCallback(callback);
void calculateMqttParams {
// ClientId格式: DeviceName|ProductKey|securemode=3,signmethod=hmacsha256,timestamp=xxx|
clientId = DEVICE_NAME + “|securemode=3,signmethod=hmacsha256,timestamp=132323232|”;
username = DEVICE_NAME + “&” + PRODUCT_KEY;
// 这里需要实现密码计算逻辑
// 实际应用中需要使用HMAC-SHA256算法
password_mqtt = “your_calculated_password”;
void callback(char* topic, byte* payload, unsigned int length) {
Serial.print(“Message arrived [“);
Serial.print(topic);
Serial.print(“] “);
String message = “”;
for (int i = 0; i < length; i++) {
message += (char)payload[i];
Serial.println(message);
// 根据接收到的消息控制LED
if (message == "on") {
digitalWrite(LED_BUILTIN, LOW); // LED on
publishMessage("LED turned ON");
} else if (message == "off") {
digitalWrite(LED_BUILTIN, HIGH); // LED off
publishMessage("LED turned OFF");
void reconnect {
while (!client.connected) {
Serial.print("Attempting MQTT connection…");
if (client.connect(clientId.c_str, username.c_str, password_mqtt.c_str)) {
Serial.println("connected");
client.subscribe(SUB_TOPIC);
publishMessage("Device connected successfully");
} else {
Serial.print("failed, rc=");
Serial.print(client.state);
Serial.println(" try again in 5 seconds");
delay(5000);
void publishMessage(String message) {
if (client.connected) {
client.publish(PUB_TOPIC, message.c_str);
void loop {
if (!client.connected) {
reconnect;
client.loop;