Arduino helps in simple interfacing for different modules. Here is an implementation of fingerprint sensor interface with Arduino Uno board. Four push buttons are used for input. The menu on LCD guides the enrollment and scanning process. The connections for hardware are described in image.
Components
- Arduino Board Uno R3
- Finger Print Sensor (https://www.adafruit.com/product/751)
- Liquid Crystal Display 16×2
- Connecting Wires
- DC Power Supply 9-12V (Optional – can be powered from USB)
Connection Diagram
Test Setup Pics
Code :
#include <LiquidCrystal.h>
#include <Adafruit_Fingerprint.h>
#include <SoftwareSerial.h>
#include <EEPROM.h>
const int buttonPin8 = 8; // the number of the pushbutton pin
const int buttonPin9 = 9; // the number of the pushbutton pin
const int buttonPin10 = 10; // the number of the pushbutton pin
const int buttonPin11 = 11; // the number of the pushbutton pin
//const int ledPin = 13; // the number of the LED pin
LiquidCrystal lcd(7, 6, 5, 4, 3, 2); // initialize the library with the numbers of the interface pins
int buttonState8 = 0;
int buttonState9 = 0;
int buttonState10 = 0;
int buttonState11 = 0;
uint8_t id =1;
uint8_t id_used =0;
int key= 0;
uint8_t getFingerprintEnroll();
//SoftwareSerial mySerial(11, 12);
Adafruit_Fingerprint finger = Adafruit_Fingerprint(&Serial);
void setup() {
pinMode(buttonPin8, INPUT);
pinMode(buttonPin9, INPUT);
pinMode(buttonPin10, INPUT);
pinMode(buttonPin11, INPUT);
lcd.begin(16, 2);
lcd.print("Biometric Fingerprint");
lcd.setCursor(0, 1);
lcd.print("Demo");
delay(500);
finger.begin(57600);
if (!finger.verifyPassword()) {
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Did not find ");
lcd.setCursor(0, 1);
lcd.print("fingerprint sensor :(");
while (1);
}
}
void loop() {
showmenu();
while((key = getkey())==0);
if (key == 1) {
id = getid();
if(id == 0)
{
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("No space");
lcd.setCursor(0, 1);
lcd.print("Del templetes");
delay(1000);
}else{
getFingerprintEnroll();
}
delay(1500);
}else if (key == 2) {
getFingerprintID();
delay(1500);
}if (key == 3) {
showDelmenu();
delay(1500);
}if (key == 4) {
}else {
//lcd.clear();
}
}
void showmenu()
{
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("1-Enroll 2-Scan ");
lcd.setCursor(0, 1);
lcd.print("3-Del ");
}
void showDelmenu()
{
lcd.clear();
lcd.setCursor(0, 0);
id_used = getUsedIdnext();
lcd.print("ID <");lcd.print(id_used);lcd.print(">");
lcd.print(" 1-Del");
lcd.setCursor(0, 1);
lcd.print("2-Up 3-Dn 4-Back");
while(getkey()!=4)
{
if(getkey()==2)
{
while(getkey()==2);
id_used = getUsedIdnext();
lcd.setCursor(0, 0);
lcd.print("ID <");lcd.print(id_used);lcd.print("> 1-Del");
}else if(getkey()==3){
while(getkey()==3);
id_used = getUsedIdprev();
lcd.setCursor(0, 0);
lcd.print("ID <");lcd.print(id_used);lcd.print("> 1-Del");
}else if(getkey()==1){
while(getkey()==1);
deleteFingerprint(id_used);
unreserveId(id_used);
id_used = getUsedIdprev();
lcd.setCursor(0, 0);
lcd.print("ID <");lcd.print(id_used);lcd.print("> 1-Del");
}
}
}
int getkey()
{
if( digitalRead(buttonPin8)){
while( digitalRead(buttonPin8));
return 1;
}else if(digitalRead(buttonPin9)){
while( digitalRead(buttonPin9));
return 2;
}else if(digitalRead(buttonPin10)){
while( digitalRead(buttonPin10));
return 3;
}else if(digitalRead(buttonPin11)){
while( digitalRead(buttonPin11));
return 4;
}else{return 0;}
}
int getid(){
for(id = 1 ;id <=160;id++)
{
if(EEPROM.read(id)==0)
{
return id;
}
}
if(id>160)
{
return 0;
}
}
int getUsedIdnext()
{
for(;id_used<=160;)
{
id_used++;
if(EEPROM.read(id_used)==1)
{
return id_used;
}
}
if(id_used>160)
{
return 0;
}
return id_used;
}
int getUsedIdprev()
{
if(id_used>1)
for(;id_used>0;)
{
id_used--;
if(EEPROM.read(id_used)==1)
{
return id_used;
}
}
if(id_used>160)
{
return 0;
}
return id_used;
}
void reserveId(int id){
EEPROM.write(id,1);
}
void unreserveId(int id){
EEPROM.write(id,0);
}
uint8_t getFingerprintEnroll() {
int p = -1;
lcd.print("Waiting for finger");
while (p != FINGERPRINT_OK) {
p = finger.getImage();
switch (p) {
case FINGERPRINT_OK:
lcd.clear();
lcd.print("Image taken");
break;
case FINGERPRINT_NOFINGER:
lcd.clear();
lcd.print(".");
break;
case FINGERPRINT_PACKETRECIEVEERR:
lcd.clear();
lcd.print("Communication error");
break;
case FINGERPRINT_IMAGEFAIL:
lcd.clear();
lcd.print("Imaging error");
break;
default:
lcd.clear();
lcd.print("Unknown error");
break;
}
}
// OK success!
p = finger.image2Tz(1);
switch (p) {
case FINGERPRINT_OK:
lcd.clear();
lcd.print("Image converted");
break;
case FINGERPRINT_IMAGEMESS:
lcd.clear();
lcd.print("Image too messy");
return p;
case FINGERPRINT_PACKETRECIEVEERR:
lcd.clear();
lcd.print("Communication error");
return p;
case FINGERPRINT_FEATUREFAIL:
lcd.clear();
lcd.print("Could not find fingerprint features");
return p;
case FINGERPRINT_INVALIDIMAGE:
lcd.clear();
lcd.print("Could not find fingerprint features");
return p;
default:
lcd.clear();
lcd.print("Unknown error");
return p;
}
lcd.clear();
lcd.print("Remove finger");
delay(2000);
p = 0;
while (p != FINGERPRINT_NOFINGER) {
p = finger.getImage();
}
lcd.clear();
lcd.print("ID ");lcd.print(id);
p = -1;
lcd.clear();
lcd.print("Place same finger again");
while (p != FINGERPRINT_OK) {
p = finger.getImage();
switch (p) {
case FINGERPRINT_OK:
lcd.clear();
lcd.print("Image taken");
break;
case FINGERPRINT_NOFINGER:
lcd.clear();
lcd.print(".");
break;
case FINGERPRINT_PACKETRECIEVEERR:
lcd.clear();
lcd.print("Communication error");
break;
case FINGERPRINT_IMAGEFAIL:
lcd.clear();
lcd.print("Imaging error");
break;
default:
lcd.clear();
lcd.print("Unknown error");
break;
}
}
// OK success!
p = finger.image2Tz(2);
switch (p) {
case FINGERPRINT_OK:
lcd.clear();
lcd.print("Image converted");
break;
case FINGERPRINT_IMAGEMESS:
lcd.clear();
lcd.print("Image too messy");
return p;
case FINGERPRINT_PACKETRECIEVEERR:
lcd.clear();
lcd.print("Communication error");
return p;
case FINGERPRINT_FEATUREFAIL:
lcd.clear();
lcd.print("Could not find fingerprint features");
return p;
case FINGERPRINT_INVALIDIMAGE:
lcd.clear();
lcd.print("Could not find fingerprint features");
return p;
default:
lcd.clear();
lcd.print("Unknown error");
return p;
}
// OK converted!
lcd.clear();
lcd.print("Creating model #");lcd.print(id);
p = finger.createModel();
if (p == FINGERPRINT_OK) {
lcd.clear();
lcd.print("Prints matched!");
} else if (p == FINGERPRINT_PACKETRECIEVEERR) {
lcd.clear();
lcd.print("Communication error");
return p;
} else if (p == FINGERPRINT_ENROLLMISMATCH) {
lcd.clear();
lcd.print("Fingerprints did not match");
return p;
} else {
lcd.clear();
lcd.print("Unknown error");
return p;
}
lcd.clear();
lcd.print("ID ");lcd.print(id);
p = finger.storeModel(id);
if (p == FINGERPRINT_OK) {
lcd.clear();
lcd.print("Stored at id ");lcd.print(id);
reserveId(id);
} else if (p == FINGERPRINT_PACKETRECIEVEERR) {
lcd.clear();
lcd.print("Communication error");
return p;
} else if (p == FINGERPRINT_BADLOCATION) {
lcd.clear();
lcd.print("Could not store in that location");
return p;
} else if (p == FINGERPRINT_FLASHERR) {
lcd.clear();
lcd.print("Error writing to flash");
return p;
} else {
lcd.clear();
lcd.print("Unknown error");
return p;
}
}
uint8_t getFingerprintID() {
uint8_t p = 0;
lcd.clear();
lcd.print("Place Finger");
delay(1500);
p = finger.getImage();
switch (p) {
case FINGERPRINT_OK:
lcd.clear();
lcd.print("Image taken");
break;
case FINGERPRINT_NOFINGER:
lcd.clear();
lcd.print("No finger detected");
return p;
case FINGERPRINT_PACKETRECIEVEERR:
lcd.clear();
lcd.print("Communication error");
return p;
case FINGERPRINT_IMAGEFAIL:
lcd.clear();
lcd.print("Imaging error");
return p;
default:
lcd.clear();
lcd.print("Unknown error");
return p;
}
// OK success!
p = finger.image2Tz();
switch (p) {
case FINGERPRINT_OK:
lcd.clear();
lcd.print("Image converted");
break;
case FINGERPRINT_IMAGEMESS:
lcd.clear();
lcd.print("Image too messy");
return p;
case FINGERPRINT_PACKETRECIEVEERR:
lcd.clear();
lcd.print("Communication error");
return p;
case FINGERPRINT_FEATUREFAIL:
lcd.clear();
lcd.print("Could not find fingerprint features");
return p;
case FINGERPRINT_INVALIDIMAGE:
lcd.clear();
lcd.print("Could not find fingerprint features");
return p;
default:
lcd.clear();
lcd.print("Unknown error");
return p;
}
// OK converted!
p = finger.fingerFastSearch();
if (p == FINGERPRINT_OK) {
lcd.clear();
lcd.print("Found a print match!");
} else if (p == FINGERPRINT_PACKETRECIEVEERR) {
lcd.clear();
lcd.print("Communication error");
return p;
} else if (p == FINGERPRINT_NOTFOUND) {
lcd.clear();
lcd.print("Did not find a match");
return p;
} else {
lcd.clear();
lcd.print("Unknown error");
return p;
}
// found a match!
lcd.clear();
lcd.print("Found ID #"); lcd.print(finger.fingerID);
}
uint8_t deleteFingerprint(uint8_t id) {
uint8_t p = -1;
p = finger.deleteModel(id);
if (p == FINGERPRINT_OK) {
Serial.println("Deleted!");
} else if (p == FINGERPRINT_PACKETRECIEVEERR) {
Serial.println("Communication error");
return p;
} else if (p == FINGERPRINT_BADLOCATION) {
Serial.println("Could not delete in that location");
return p;
} else if (p == FINGERPRINT_FLASHERR) {
Serial.println("Error writing to flash");
return p;
} else {
Serial.print("Unknown error: 0x"); Serial.println(p, HEX);
return p;
}
}
Complete code can be downloaded here: arduino_fingerprint