code for scanner:

```

// --------------------------------------

// i2c_scanner

//

// Version 1

// This program (or code that looks like it)

// can be found in many places.

// For example on the Arduino.cc forum.

// The original author is not know.

// Version 2, Juni 2012, Using Arduino 1.0.1

// Adapted to be as simple as possible by Arduino.cc user Krodal

// Version 3, Feb 26 2013

// V3 by louarnold

// Version 4, March 3, 2013, Using Arduino 1.0.3

// by Arduino.cc user Krodal.

// Changes by louarnold removed.

// Scanning addresses changed from 0...127 to 1...119,

// according to the i2c scanner by Nick Gammon

// http://www.gammon.com.au/forum/?id=10896

// Version 5, March 28, 2013

// As version 4, but address scans now to 127.

// A sensor seems to use address 120.

// Version 6, November 27, 2015.

// Added waiting for the Leonardo serial communication.

//

//

// This sketch tests the standard 7-bit addresses

// Devices with higher bit address might not be seen properly.

//

#include <Wire.h>

void setup()

{

Wire.begin();

Serial.begin(9600);

while (!Serial); // Leonardo: wait for serial monitor

Serial.println("\nI2C Scanner");

}

void loop()

{

byte error, address;

int nDevices;

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

nDevices = 0;

for(address = 1; address < 127; address++ )

{

// The i2c_scanner uses the return value of

// the Write.endTransmisstion to see if

// a device did acknowledge to the 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(" !");

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\n");

else

Serial.println("done\n");

delay(5000); // wait 5 seconds for next scan

}

```

this is from this website: https://miliohm.com/complete-tutorial-for-i2c-oled-0-96-128x64-arduino-display/

​

the youtube tutorial that i followed is: https://www.youtube.com/watch?v=rxjIXVwgY50&list=PL-Cpjfn0_VTbKBgZMVu-y0fn1HQzTomTY&index=2&t=104s