i2c_scanner.ino

#include <Wire.h>

void setup() {
  Serial.begin(115200);
  Wire.begin();
  Serial.println("\nI2C Scanner");
}

void loop() {
  byte error, address;
  int nDevices;

  Serial.println("Scanning...");

  nDevices = 0;
  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.println(address, HEX);

		  nDevices++;
	  }
	  else if (error == 4) {
		  Serial.print("Unknown error at address 0x");
		  if (address < 16) {
			  Serial.print("0");
		  }
		  Serial.println(address, HEX);
	  }
  }
  if (nDevices == 0) {
	  Serial.println("No I2C devices found");
  }
  else {
	  Serial.println("done");
  }

  delay(5000);
}