/* Basic MQTT example with Authentication - connects to an MQTT server, providing username and password - publishes "hello world" to the topic "outTopic" - subscribes to the topic "inTopic" */ #include #include #include // Update these with values suitable for your network. byte mac[] = { 0xDE, 0xED, 0xBA, 0xFE, 0xFE, 0xED }; IPAddress ip(172, 16, 0, 100); IPAddress server(172, 16, 0, 2); void callback(char* topic, byte* payload, unsigned int length) { // handle message arrived } EthernetClient ethClient; PubSubClient client(server, 1883, callback, ethClient); void setup() { Ethernet.begin(mac, ip); // Note - the default maximum packet size is 128 bytes. If the // combined length of clientId, username and password exceed this, // you will need to increase the value of MQTT_MAX_PACKET_SIZE in // PubSubClient.h if (client.connect("arduinoClient", "testuser", "testpass")) { client.publish("outTopic","hello world"); client.subscribe("inTopic"); } } void loop() { client.loop(); }