/* Reconnecting MQTT example - non-blocking This sketch demonstrates how to keep the client connected using a non-blocking reconnect function. If the client loses its connection, it attempts to reconnect every 5 seconds without blocking the main loop. */ #include #include #include // Update these with values suitable for your hardware/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(ethClient); long lastReconnectAttempt = 0; boolean reconnect() { if (client.connect("arduinoClient")) { // Once connected, publish an announcement... client.publish("outTopic","hello world"); // ... and resubscribe client.subscribe("inTopic"); } return client.connected(); } void setup() { client.setServer(server, 1883); client.setCallback(callback); Ethernet.begin(mac, ip); delay(1500); lastReconnectAttempt = 0; } void loop() { if (!client.connected()) { long now = millis(); if (now - lastReconnectAttempt > 5000) { lastReconnectAttempt = now; // Attempt to reconnect if (reconnect()) { lastReconnectAttempt = 0; } } } else { // Client connected client.loop(); } }