#include <Wire.h>

  void i2c_eeprom_write_byte( int deviceaddress, unsigned int eeaddress, byte data ) {
    int rdata = data;
    Wire.beginTransmission(deviceaddress);
    Wire.write((int)(eeaddress)); // odešle vyšší byte
    Wire.write((int)(eeaddress & 0xFF)); // odešle nižší byte
    Wire.write(rdata);
    Wire.endTransmission();
  }

  byte i2c_eeprom_read_byte( int deviceaddress, unsigned int eeaddress ) {
    byte rdata = 0xFF;
    Wire.beginTransmission(deviceaddress);
    Wire.write((int)(eeaddress)); // odešle vyšší byte
    Wire.write((int)(eeaddress & 0xFF)); // odešle nižší byte
    Wire.endTransmission();
    Wire.requestFrom(deviceaddress,1);
    if (Wire.available()) rdata = Wire.read();
    return rdata;
  }

 void setup()
  {
    Wire.begin();
    Serial.begin(9600);

    i2c_eeprom_write_byte(0x50, 2574, 147);
    delay(5);
    byte a = i2c_eeprom_read_byte(0x50, 2574);
    Serial.print("Hodnota je: ");
    Serial.println(a);
  }

  void loop() {}