發(fā)布信息，控制ESP8266管腳電壓毒费，實(shí)現(xiàn)控制。
#include <ESP8266WiFi.h>
#include <PubSubClient.h>
#define LED D8
// WiFi
const char *ssid = "XXXX"; // Enter your WiFi name
const char *password = "XXXXXX";? // Enter WiFi password
// MQTT Broker
const char *mqtt_broker = "192.168.3.200";
const char *topic = "led"; //訂閱主題
const char *mqtt_username = "emqx";
const char *mqtt_password = " ";
const int mqtt_port = 1883;
WiFiClient espClient;
PubSubClient client(espClient);
void setup() {
? ? // Set software serial baud to 115200;
? ? Serial.begin(115200);
? ? pinMode(LED,OUTPUT);
? ? // connecting to a WiFi network
? ? WiFi.begin(ssid, password);
? ? while (WiFi.status() != WL_CONNECTED) {
? ? ? ? delay(500);
? ? ? ? Serial.println("Connecting to WiFi..");
? ? }
? ? Serial.println("Connected to the WiFi network");
? ? //connecting to a mqtt broker
? ? client.setServer(mqtt_broker, mqtt_port);
? ? client.setCallback(callback);
? ? while (!client.connected()) {
? ? ? ? String client_id = "esp8266-client-";
? ? ? ? client_id += String(WiFi.macAddress());
? ? ? ? Serial.printf("The client %s connects to the public mqtt broker\n", client_id.c_str());
? ? ? ? if (client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
? ? ? ? ? ? Serial.println("Public emqx mqtt broker connected");
? ? ? ? } else {
? ? ? ? ? ? Serial.print("failed with state ");
? ? ? ? ? ? Serial.print(client.state());
? ? ? ? ? ? delay(2000);
? ? ? ? }
? ? }
? ? // publish and subscribe
? ? client.publish(topic, "hello emqx");
? ? client.subscribe(topic);
}
void callback(char *topic, byte *payload, unsigned int length) {
? ? Serial.print("Message arrived in topic: ");
? ? Serial.println(topic);
? ? Serial.print("Message:");
? ? String message;
? ? for (int i = 0; i < length; i++) {
? ? ? ? message = message + (char) payload[i];? // convert *byte to string
? ? }
//? ? Serial.print(message);
? ? if (message == "on")? { digitalWrite(LED, HIGH); }? // LED on
? ? if (message == "off") { digitalWrite(LED, LOW); } // LED off
//? ? Serial.print("hello ");
? ? Serial.println();
? ? Serial.println("-----------------------");
}
void loop() {
? ? client.loop();
}
只要發(fā)送? on?或?off?給? 訂閱主題? led 愈魏，就能控制D8?腳?的高低電平觅玻，實(shí)現(xiàn)控制。
