OTP Based Door Lock Using Arduino And SIM800L

 

Circuit Diagram :-

Code :- 

//Prateek //wwww.prateeks.in //https://www.youtube.com/c/JustDoElectronics/videos #include <SoftwareSerial.h> #include <Wire.h> #include <LiquidCrystal_I2C.h> #include <Keypad.h> #define relay 4 #define red 16 #define green 15 const byte ROWS = 4; const byte COLS = 4; char hexaKeys[ROWS][COLS] = { {'1', '2', '3', 'A'}, {'4', '5', '6', 'B'}, {'7', '8', '9', 'C'}, {'*', '0', '#', 'D'} }; byte rowPins[ROWS] = {13, 12, 11, 10}; byte colPins[COLS] = {9, 8, 7, 6}; Keypad customKeypad = Keypad( makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS); LiquidCrystal_I2C lcd(0x27, 16, 2); SoftwareSerial sim800l(3, 2); int irsensor = A0; int otp; String otpstring = ""; int i = 0; void setup() { pinMode(irsensor, INPUT_PULLUP); sim800l.begin(4800); Serial.begin(115200); lcd.init(); lcd.backlight(); Serial.print("Welcome to SIM800L Project"); sim800l.println("AT"); updateSerial(); pinMode(relay, OUTPUT); pinMode(red, INPUT); pinMode(green, INPUT); digitalWrite(relay, LOW); delay(500); sim800l.println("AT+CSQ"); updateSerial(); delay(1000); } void updateSerial() { delay(500); while (Serial.available()) { sim800l.write(Serial.read()); } while (sim800l.available()) { Serial.write(sim800l.read()); } } void loop() { lcd.setCursor(0, 0); lcd.print(" OTP Based"); lcd.setCursor(0, 1); lcd.print(" Door Lock"); if (digitalRead(irsensor) == LOW) { otp = random(2000, 9999); otpstring = String(otp); Serial.println(otpstring); while (digitalRead(irsensor) == LOW) {} lcd.clear(); lcd.setCursor(0, 0); lcd.print(" OTP Sent to"); lcd.setCursor(0, 1); lcd.print(" Your Mobile"); Serial.print("OTP is "); delay(100); Serial.println(otpstring); delay(100); SendSMS(); lcd.clear(); lcd.setCursor(0, 0); lcd.print("Enter OTP :"); getotp(); } } void getotp() { String y = ""; int a = y.length(); while (a < 4) { char customKey = customKeypad.getKey(); if (customKey) { lcd.setCursor(0, 1); y = y + customKey; lcd.print(y); a = y.length(); } } Serial.print("Entered OTP is "); Serial.println(y); if (otpstring == y) { lcd.setCursor(0, 0); lcd.print("Access Granted"); lcd.setCursor(0, 1); lcd.print("Door Opening"); digitalWrite(relay, HIGH); digitalWrite(red, HIGH); digitalWrite(green, LOW); delay(5000); digitalWrite(relay, LOW); digitalWrite(red, LOW); digitalWrite(green, HIGH); } else { lcd.setCursor(0, 0); lcd.print("Access Failed"); lcd.setCursor(0, 1); lcd.print("Try Again !!!"); delay(3000); } } void SendSMS() { Serial.println("Sending SMS..."); sim800l.print("AT+CMGF=1\r"); delay(100); sim800l.print ("AT+CSMP=17,167,0,0\r"); delay(500); sim800l.print("AT+CMGS=\"+91xxxxxxxxxxx\"\r"); delay(500); sim800l.print("Your OTP is " + otpstring + " Just Type OTP And Unlock The Door"); delay(500); sim800l.print((char)26); delay(500); sim800l.println(); Serial.println("Text Sent."); delay(500); }


Video :-