#include <Wire.h>

void setup() {
  Serial.begin(9600);  // start serial for output
  Wire.onRequest(requestEvent); // register event
}

void loop() {
  Wire.end();
  Wire.begin(pickARandomAddress());                // join i2c bus with address #8
  delay(2000);
}

// function that executes whenever data is requested by master
// this function is registered as an event, see setup()
void requestEvent() {
  Serial.println("WARNING! We have been detected!!");
  Wire.write("hello ");
}

int pickARandomAddress() {
  int busMinAddress = 1;
  int busMaxAddress = 50;
  return random(busMinAddress, busMaxAddress);
}