Wiring
Check pinout, power supply, common GND and voltage levels before connecting the module.
Full code
#include <Wire.h>
void setup() {
Wire.begin();
Serial.begin(9600);
Serial.println("I2C scanner");
}
void loop() {
for (byte address = 1; address < 127; address++) {
Wire.beginTransmission(address);
if (Wire.endTransmission() == 0) {
Serial.print("Found I2C device at 0x");
Serial.println(address, HEX);
}
}
delay(3000);
}How it works
This lesson matches the page title and gives a clean starting point for this exact example.
Common mistakes
Check board selection, wiring, libraries, power supply and serial monitor baud rate.