免费公益 MQTT 服务
mqttyyc.top

// npm install mqtt
const mqtt = require('mqtt');
const client = mqtt.connect('mqtts://mqttyyc.top:8883', {
  username: 'your_username',
  password: 'your_password',
});

client.on('connect', () => {
  client.subscribe('myproj/sensor/#');
  client.publish('myproj/sensor/temp', '26.5');
});
// 浏览器里请改用 wss://mqttyyc.top:8084/mqtt

# pip install paho-mqtt
import paho.mqtt.client as mqtt

client = mqtt.Client()
client.username_pw_set('your_username', 'your_password')
client.tls_set()  # 开启 TLS，连 8883
client.connect('mqttyyc.top', 8883)
client.loop_forever()

// Arduino IDE 里安装 PubSubClient 库
#include <PubSubClient.h>

PubSubClient mqtt(wifiClient);

mqtt.setServer("mqttyyc.top", 1883);
mqtt.connect("device-001", "your_username", "your_password");

# MQTTX 新建连接，照填即可
Name:     mqttyyc
Host:     mqttyyc.top
Port:     8883   （勾选 SSL/TLS）
Username: your_username
Password: your_password

# 想用 WebSocket 的话：
Host:     wss://mqttyyc.top
Port:     8084  （路径 /mqtt 会自动带上）