@adrian I would try something like this: /* * Documentation: http://www.mysensors.org * Support Forum: http://forum.mysensors.org * * http://www.mysensors.org/build/relay */ // Enable debug prints to serial monitor #define MY_DEBUG // Enable and select radio type attached #define MY_RADIO_NRF24 //#define MY_RADIO_RFM69 // Enabled repeater feature for this node #define MY_REPEATER_FEATURE #define MY_NODE_ID 1 #include <SPI.h> #include <MySensors.h> #include <Bounce2.h> #define RELAY_PIN 5 // Arduino Digital I/O pin number for relay #define BUTTON_PIN 3 // Arduino Digital I/O pin number for button #define CHILD_ID 1 #define RELAY_ON 1 #define RELAY_OFF 0 Bounce debouncer = Bounce(); bool state = false; bool initialValueSent = false; MyMessage msg(CHILD_ID, V_STATUS); void setup() { // Setup the button pinMode(BUTTON_PIN, INPUT_PULLUP); // After setting up the button, setup debouncer debouncer.attach(BUTTON_PIN); debouncer.interval(10); // Make sure relays are off when starting up digitalWrite(RELAY_PIN, RELAY_OFF); // Then set relay pins in output mode pinMode(RELAY_PIN, OUTPUT); // Set relay to last known state (using eeprom storage) state = loadState(CHILD_ID); digitalWrite(RELAY_PIN, state?RELAY_ON:RELAY_OFF); } void presentation() { sendSketchInfo("Lamp", "1.0"); present(CHILD_ID, S_BINARY); } void loop() { if (!initialValueSent) { Serial.println("Sending initial value"); send(msg.set(state?RELAY_ON:RELAY_OFF)); Serial.println("Requesting initial value from controller"); request(CHILD_ID, V_STATUS); wait(2000, C_SET, V_STATUS); } if (debouncer.update()) { if (debouncer.read()==LOW) { state = !state; send(msg.set(state?RELAY_ON:RELAY_OFF), true); // Send new state and request ack back } } } void receive(const MyMessage &message) { if (message.isAck()) { Serial.println("This is an ack from gateway"); } if (message.type == V_STATUS) { if (!initialValueSent) { Serial.println("Receiving initial value from controller"); initialValueSent = true; } // Change relay state state = (bool)message.getInt(); digitalWrite(RELAY_PIN, state?RELAY_ON:RELAY_OFF); send(msg.set(state?RELAY_ON:RELAY_OFF)); // Store state in eeprom saveState(CHILD_ID, state); // Write some debug info Serial.print("Incoming change for sensor:"); Serial.print(message.sensor); Serial.print(", New status: "); Serial.println(message.getInt()); } } Node serial log: Starting repeater (RNNRA-, 2.0.0) TSM:INIT TSM:RADIO:OK TSP:ASSIGNID:OK (ID=1) TSM:FPAR TSP:MSG:SEND 1-1-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc: TSP:MSG:READ 0-0-1 s=255,c=3,t=8,pt=1,l=1,sg=0:0 TSP:MSG:FPAR RES (ID=0, dist=0) TSP:MSG:PAR OK (ID=0, dist=1) TSM:FPAR:OK TSM:ID TSM:CHKID:OK (ID=1) TSM:UPL TSP:PING:SEND (dest=0) TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=24,pt=1,l=1,sg=0,ft=0,st=ok:1 TSP:MSG:READ 0-0-1 s=255,c=3,t=25,pt=1,l=1,sg=0:1 TSP:MSG:PONG RECV (hops=1) TSP:CHKUPL:OK TSM:UPL:OK TSM:READY TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=15,pt=6,l=2,sg=0,ft=0,st=ok:0100 TSP:MSG:SEND 1-1-0-0 s=255,c=0,t=18,pt=0,l=5,sg=0,ft=0,st=ok:2.0.0 TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=6,pt=1,l=1,sg=0,ft=1,st=ok:0 TSP:MSG:READ 0-0-1 s=255,c=3,t=6,pt=0,l=1,sg=0:M TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=11,pt=0,l=4,sg=0,ft=0,st=ok:Lamp TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=12,pt=0,l=3,sg=0,ft=0,st=ok:1.0 TSP:MSG:SEND 1-1-0-0 s=1,c=0,t=3,pt=0,l=0,sg=0,ft=0,st=ok: Request registration... TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=26,pt=1,l=1,sg=0,ft=0,st=ok:2 TSP:MSG:READ 0-0-1 s=255,c=3,t=27,pt=1,l=1,sg=0:1 Node registration=1 Init complete, id=1, parent=0, distance=1, registration=1 Sending initial value TSP:MSG:SEND 1-1-0-0 s=1,c=1,t=2,pt=2,l=2,sg=0,ft=0,st=ok:0 Requesting initial value from controller TSP:MSG:SEND 1-1-0-0 s=1,c=2,t=2,pt=0,l=0,sg=0,ft=0,st=ok: TSP:MSG:READ 0-0-1 s=1,c=1,t=2,pt=0,l=1,sg=0:0 Receiving initial value from controller TSP:MSG:SEND 1-1-0-0 s=1,c=1,t=2,pt=2,l=2,sg=0,ft=0,st=ok:0 Incoming change for sensor:1, New status: 0 TSP:MSG:SEND 1-1-0-0 s=1,c=1,t=2,pt=2,l=2,sg=0,ft=0,st=ok:1 TSP:MSG:READ 0-0-1 s=1,c=1,t=2,pt=2,l=2,sg=0:1 This is an ack from gateway TSP:MSG:SEND 1-1-0-0 s=1,c=1,t=2,pt=2,l=2,sg=0,ft=0,st=ok:1 Incoming change for sensor:1, New status: 1 TSP:MSG:SEND 1-1-0-0 s=1,c=1,t=2,pt=2,l=2,sg=0,ft=0,st=ok:0 TSP:MSG:READ 0-0-1 s=1,c=1,t=2,pt=2,l=2,sg=0:0 This is an ack from gateway TSP:MSG:SEND 1-1-0-0 s=1,c=1,t=2,pt=2,l=2,sg=0,ft=0,st=ok:0 Incoming change for sensor:1, New status: 0 Btw, message.getBool() always returns 0 in my tests, so I switched to message.getInt() in the sketch above. Can anyone confirm that message.getBool is working in 2.0.0?