Accessing secret data

In the last section of this chapter, we are going to use all the hardware that we connected to the project for another cool application: accessing a secret piece of data with your fingerprint.

It can, for example, be a secret code that you only want to be accessible with your own fingerprint. We will use the LCD screen for this, removing the need to have the serial monitor opened.

The following is the complete code for this part, excluding the functions to read the fingerprint sensor data:

// Libraries
#include <Adafruit_Fingerprint.h>
#include <SoftwareSerial.h>
#include <LiquidCrystal_I2C.h>
#include <Wire.h>

// LCD Screen instance
LiquidCrystal_I2C lcd(0x27,20,4);

// Function to get fingerprint
int getFingerprintIDez();

// Init Software Serial
SoftwareSerial mySerial(2, 3);

// Fingerprint sensor instance
Adafruit_Fingerprint finger = Adafruit_Fingerprint(&mySerial);

// Relay parameters
int relayPin = 7;
bool relayState = false;

// Your...