#include <EEPROM.h>

void print_eeprom_contents() {
  for (int i = 0; i < EEPROM.length(); i++) {
    byte data = EEPROM.read(i);
    if (i % 16 == 0) { // group output by 8 characters per line
      Serial.println();
      //Serial.print("0x");
      //Serial.print(i, HEX);
      //Serial.print(i);
      printFormattedNumber(i);
      Serial.print(" : ");
    }
    Serial.print((char)data);
  }
}

void fillRandomData(){
    randomSeed(analogRead(0)); // Seed the random number generator with a random value from the analog input
  for (int i = 0; i < EEPROM.length(); i++) {
    char c;
    /*
    if (i % 3 == 0) {
      c = '0' + random(10); // Generate a random digit
    } else if (i % 3 == 1) {
      c = 'A' + random(26); // Generate a random uppercase letter
    } else {
      c = 'a' + random(26); // Generate a random lowercase letter
    }
    */
    c = '0' + random(10); // Generate a random digit
    EEPROM.write(i, c); // Write the character to the current address in EEPROM
  }
  Serial.println("EEPROM filled with random characters.");
}

void printFormattedNumber(int num) {
  char buffer[5]; // Buffer to hold the formatted number
  sprintf(buffer, "%04d", num); // Format the number with leading zeros
  Serial.print(buffer); // Print the formatted number
}

void setup() {
  Serial.begin(9600);
  fillRandomData();
  print_eeprom_contents();
}

void loop() {
  // Do nothing
}