// Wire Slave Receiver // by Nicholas Zambetti // Demonstrates use of the Wire library // Receives data as an I2C/TWI slave device // Refer to the "Wire Master Writer" example for use with this // Created 29 March 2006 // This example code is in the public domain. #include int led = LED_BUILTIN; void setup() { pinMode(led, OUTPUT); Wire.begin(9); // join i2c bus with address #9 Wire.onReceive(receiveEvent); // register event Serial.begin(9600); // start serial for output } void loop() { delay(100); } // function that executes whenever data is received from master // this function is registered as an event, see setup() void receiveEvent(int howMany) { digitalWrite(led, HIGH); // briefly flash the LED while(Wire.available() > 1) { // loop through all but the last char c = Wire.read(); // receive byte as a character Serial.print(c); // print the character } int x = Wire.read(); // receive byte as an integer Serial.println(x); // print the integer digitalWrite(led, LOW); }