esp8266阿里云点灯

要实现esp8266连接阿里云并控制灯的话，可以参考以下步骤：

1. 在阿里云物联网平台创建产品和设备，并获取设备的三元组信息（ProductKey、DeviceName、DeviceSecret）。
2. 在esp8266上安装MQTT客户端库，例如PubSubClient。
3. 编写esp8266的代码，连接WiFi和阿里云MQTT服务器，并订阅/发布对应的主题。
4. 在阿里云物联网平台上创建数据流转规则，将设备上报的数据转发到控制台或其他设备。

下面是一个简单的示例代码，可以实现通过阿里云控制台控制esp8266上的LED灯：

#include <ESP8266WiFi.h>
#include <PubSubClient.h>

const char* ssid = "your_SSID";
const char* password = "your_PASSWORD";
const char* mqttServer = "your_MQTT_SERVER";
const int mqttPort = 1883;
const char* mqttUser = "your_MQTT_USER";
const char* mqttPassword = "your_MQTT_PASSWORD";
const char* productKey = "your_PRODUCT_KEY";
const char* deviceName = "your_DEVICE_NAME";
const char* deviceSecret = "your_DEVICE_SECRET";

WiFiClient espClient;
PubSubClient client(espClient);

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);
  Serial.begin(115200);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");
  client.setServer(mqttServer, mqttPort);
  client.setCallback(callback);
  while (!client.connected()) {
    String clientId = "ESP8266Client-";
    clientId += String(random(0xffff), HEX);
    if (client.connect(clientId.c_str(), mqttUser, mqttPassword)) {
      Serial.println("Connected to MQTT server");
      String topic = "/" + String(productKey) + "/" + String(deviceName) + "/user/get";
      client.subscribe(topic.c_str());
      topic = "/" + String(productKey) + "/" + String(deviceName) + "/user/update";
      client.subscribe(topic.c_str());
    } else {
      Serial.print("Failed to connect to MQTT server, rc=");
      Serial.println(client.state());
      delay(5000);
    }
  }
}

void loop() {
  client.loop();
}

void callback(char* topic, byte* payload, unsigned int length) {
  Serial.print("Received message [");
  Serial.print(topic);
  Serial.print("]: ");
  for (int i = 0; i < length; i++) {
    Serial.print((char)payload[i]);
  }
  Serial.println();
  if (strcmp(topic, ("/" + String(productKey) + "/" + String(deviceName) + "/user/update").c_str()) == 0) {
    if ((char)payload[0] == '1') {
      digitalWrite(LED_BUILTIN, LOW);
      Serial.println("LED turned on");
    } else {
      digitalWrite(LED_BUILTIN, HIGH);
      Serial.println("LED turned off");
    }
  }
}