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Project Blueprint 05 // Advanced Defense

Biometric Fingerprint Solenoid Smart Lock

An optical authentication security node using flash memory database registers to validate unique user IDs and command physical relay locks.

Optical Sensor & Relay Interface Matrix

Component Pin Type Vector Arduino Uno Target Pin
AS608 Sensor VCC (3.3V) ====> 3.3V Rail Pin
AS608 Sensor TX ====> Digital Pin 2 (Software RX)
AS608 Sensor RX ====> Digital Pin 3 (Software TX)
5V Relay Signal (IN) ====> Digital Pin 7

Biometric Authentication Firmware

#include 

SoftwareSerial mySerial(2, 3); // RX, TX pins
Adafruit_Fingerprint finger = Adafruit_Fingerprint(&mySerial);
const int relayPin = 7;

void setup() {
 Serial.begin(9600);
 pinMode(relayPin, OUTPUT);
 digitalWrite(relayPin, LOW); // Safe Lock State
 
 finger.begin(57600);
 if (finger.verifyPassword()) {
  Serial.println("Secure Scanner Module Found.");
 }
}

void loop() {
 verifyBiometrics();
 delay(50);      
}

int verifyBiometrics() {
 uint8_t imageResult = finger.getImage();
 if (imageResult != FINGERPRINT_OK) return -1;

 imageResult = finger.image2Tz();
 if (imageResult != FINGERPRINT_OK) return -1;

 imageResult = finger.fingerFastSearch();
 if (imageResult != FINGERPRINT_OK) {
  Serial.println("Access Flag: DENIED - Unknown Matrix Signature");
  return -1;
 }
 
 // Verified Pass
 Serial.print("Access Flag: GRANTED - System ID matched: #"); 
 Serial.println(finger.fingerID);
 digitalWrite(relayPin, HIGH); // Disengage Solenoid Deadbolt
 delay(4000);         // Hold open 4 seconds
 digitalWrite(relayPin, LOW); // Secure Lock
 return finger.fingerID;
}