#include <Wire.h>

void setup() {
  Serial.begin(9600);
  Wire.begin();
  while (!Serial); // Wait for serial port to be available
  Serial.println("\nI2C Scanner");
}

void loop() {
  byte error, address;
  int deviceCount = 0;

  Serial.println("Scanning...");
  
  for(address = 1; address < 127; address++ ) {
    Wire.beginTransmission(address);
    error = Wire.endTransmission();
    
    if (error == 0) {
      Serial.print("I2C device found at address 0x");
      if (address<16) {
        Serial.print("0");
      }
      Serial.print(address,HEX);
      Serial.println("  !");
      deviceCount++;
    }
    else if (error==4) {
      Serial.print("Unknown error at address 0x");
      if (address<16) {
        Serial.print("0");
      }
      Serial.println(address,HEX);
    }    
  }

  if (deviceCount == 0) {
    Serial.println("No I2C devices found\n");
  }
  else {
    Serial.println("Done\n");
  }
  delay(5000); // wait 5 seconds for the next scan
}