Merging two C language codes into one of Arduino

[sindhu05]

Hello, I have two codes in C language which are to be merged and used in Arduino, in order to make the code for a Gate Lock...
However, I am not getting as to how can I combine these two codes.
Can anyone help out and give some idea for me to start with? Or some link/reference by which I can fully understand this?
Any sort of help would be really appreciated! Thank you.

Here's the code for keypad door lock with Bluetooth and Android app using Arduino,

/LCD config
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x3f,20,4);

#include <Servo.h>
#include <Keypad.h>

//Variables
int mot_min = 90;   //min servo angle  (set yours)
int mot_max = 180; //Max servo angle   (set yours)
int character = 0;
int activated =0;
char Received = 'c';
char Str[16] = {' ', ' ', ' ', ' ', ' ', ' ', '-', '*', '*', '*', ' ', ' ', ' ', ' ', ' ', ' '};  

//Pins
Servo myservo;
int buzzer=11;     //pin for the buzzer beep
int external = 12; //pin to inside open
int internal = 13; //pin to inside close

//Keypad config
const byte ROWS = 4; //four rows
const byte COLS = 4; //four columns
//define the cymbols on the buttons of the keypads
char hexaKeys[ROWS][COLS] = {
  {'1','4','7','*'},
  {'2','5','8','0'},
  {'3','6','9','#'},
  {'A','B','C','D'}
};
byte rowPins[ROWS] = {5, 4, 3, 2}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {9, 8, 7, 6}; //connect to the column pinouts of the keypad

//initialize an instance of class NewKeypad
Keypad customKeypad = Keypad( makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS); 

void setup(){
  Serial.begin(9600);
  myservo.attach(10); //attach the servo to pin D10
  pinMode(buzzer,OUTPUT); 
  pinMode(external,INPUT);
  pinMode(internal,INPUT); 
  //Init the screen and print the first text
  lcd.init();
  lcd.backlight();
  lcd.clear();
  lcd.print("    PASSWORD");
  lcd.setCursor(0,1);
  lcd.print("      -***     ");
  //put the servo in the close position first
  myservo.write(mot_min);  
  
}
  
void loop(){


///////////////Android OPEN/CLOSE/////////  
  if(Serial.available()>0)
 { 
    
    char Received = Serial.read();

    if (Received == 'c')
    {
      myservo.write(mot_min);
      activated = 0;
      character=0;
      Str[6]= '-';
      Str[7]= '*'; 
      Str[8]= '*'; 
      Str[9]= '*';
      Str[10]= ' ';   
      lcd.clear();
      lcd.setCursor(0,0);
      lcd.print("    PASSWORD");    
      lcd.setCursor(0,1);
      lcd.print(Str);  
    }
    if (Received == 'o')
    {
      myservo.write(mot_max);
      lcd.clear();
      lcd.setCursor(0,0);
      lcd.print("  ANDROID OPEN");
      activated = 2;
      analogWrite(buzzer,240);
      delay(250);
      analogWrite(buzzer,200);
      delay(250);
      analogWrite(buzzer,180);
      delay(250);
      analogWrite(buzzer,250);
      delay(250);
      analogWrite(buzzer,LOW);
     
      
      lcd.clear();    
      lcd.setCursor(4,0);
      lcd.print("WELLCOME");
      
      lcd.setCursor(2,1);
      lcd.print("ELECTRONOOBS");
      

      lcd.clear();    
      lcd.setCursor(3,0);
      lcd.print("DOOR  OPEN");
      lcd.setCursor(2,1);
      lcd.print("ELECTRONOOBS");
      delay(500);
    }
    
    
    
 }



  
///////////////EMERGENCY OPEN/CLOSE/////////
  if (digitalRead(external))
  {
      myservo.write(mot_max);
      lcd.clear();
      lcd.setCursor(2,0);
      lcd.print("INSIDE  OPEN");
      activated = 2;
      analogWrite(buzzer,240);
      delay(250);
      analogWrite(buzzer,200);
      delay(250);
      analogWrite(buzzer,180);
      delay(250);
      analogWrite(buzzer,250);
      delay(250);
      analogWrite(buzzer,LOW);
     
      
      lcd.clear();    
      lcd.setCursor(4,0);
      lcd.print("WELLCOME");
      
      lcd.setCursor(2,1);
      lcd.print("ELECTRONOOBS");
      

      lcd.clear();    
      lcd.setCursor(3,0);
      lcd.print("DOOR  OPEN");
      lcd.setCursor(2,1);
      lcd.print("ELECTRONOOBS");
      delay(500);
    
  }

  if (digitalRead(internal))
  {
    myservo.write(mot_min);
    activated = 0;
    character=0;
    Str[6]= '-';
    Str[7]= '*'; 
    Str[8]= '*'; 
    Str[9]= '*';
    Str[10]= ' ';   
    lcd.clear();
    lcd.setCursor(0,0);
    lcd.print("    PASSWORD");    
    lcd.setCursor(0,1);
    lcd.print(Str);
  }
    
///////////////KEYPAD OPEN/CLOSE////////////  
  char customKey = customKeypad.getKey(); //this function reads the presed key
  
  if (customKey){
  analogWrite(buzzer,200);
    if (character ==0)
    {  
    Serial.println(customKey);

    Str[6]= customKey;   
    lcd.clear();
    lcd.setCursor(0,0);
    lcd.print("    PASSWORD");    
    lcd.setCursor(0,1);
    lcd.print(Str);
   
    }

    if (character ==1)
    {  
    Serial.println(customKey);
    Str[7]= customKey;   
    lcd.clear();
    lcd.setCursor(0,0);
    lcd.print("    PASSWORD");    
    lcd.setCursor(0,1);
    lcd.print(Str);
   
    }

    if (character ==2)
    {  
    Serial.println(customKey);
    Str[8]= customKey;   
    lcd.clear();
    lcd.setCursor(0,0);
    lcd.print("    PASSWORD");    
    lcd.setCursor(0,1);
    lcd.print(Str);
   
    }

    if (character ==3)
    {  
    Serial.println(customKey);
    Str[9]= customKey;   
    lcd.clear();
    lcd.setCursor(0,0);
    lcd.print("    PASSWORD");    
    lcd.setCursor(0,1);
    lcd.print(Str);
   
    }

    if (character ==4)
    {  
    Serial.println(customKey);
    Str[10]= customKey;
    activated=1;
   
    }
    character=character+1;
    delay(100);
    analogWrite(buzzer,LOW);
  }

  if (activated == 1)
    {
/*Change your password below!!! 
Change each of Str[6], Str[7], Str[8], Str[9]*/

    if(Str[10]='A' && character==5 && Str[6]=='3' && Str[7]=='0' && Str[8]=='0' && Str[9]=='7' )
    {
      myservo.write(mot_max);
      lcd.clear();
      lcd.setCursor(4,0);
      lcd.print("ACCEPTED");
      activated = 2;
      analogWrite(buzzer,240);
      delay(250);
      analogWrite(buzzer,200);
      delay(250);
      analogWrite(buzzer,180);
      delay(250);
      analogWrite(buzzer,250);
      delay(250);
      analogWrite(buzzer,LOW);
      delay(1000);
      
      lcd.clear();    
      lcd.setCursor(4,0);
      lcd.print("WELLCOME");
      delay(500);
      lcd.setCursor(2,1);
      lcd.print("ELECTRONOOBS");
      delay(1000);

      lcd.clear();    
      lcd.setCursor(3,0);
      lcd.print("DOOR  OPEN");
      lcd.setCursor(2,1);
      lcd.print("ELECTRONOOBS");
      
    }
    else
    {
      lcd.clear();    
      lcd.setCursor(1,0);
      lcd.print("PASSWORD ERROR");
      lcd.setCursor(3,1);
      lcd.print("TRY  AGAIN");
      analogWrite(buzzer,150);
      delay(3000);
      analogWrite(buzzer,LOW);
      character=0;
      Str[6]= '-';
      Str[7]= '*'; 
      Str[8]= '*'; 
      Str[9]= '*';
      Str[10]= ' ';
      activated = 0;
      lcd.clear();    
      lcd.setCursor(4,0);
      lcd.print("PASSWORD");
      lcd.setCursor(0,1);
      lcd.print(Str);   
    }
  }
  if (activated == 2)
    {
    if(customKey == 'B' )
    {
      myservo.write(mot_min);
      activated = 0;
      character=0;
      Str[6]= '-';
      Str[7]= '*'; 
      Str[8]= '*'; 
      Str[9]= '*';
      Str[10]= ' ';   
      lcd.clear();
      lcd.setCursor(0,0);
      lcd.print("    PASSWORD");    
      lcd.setCursor(0,1);
      lcd.print(Str);
     
    }
  }  
}

What I want is to merge this following code into the above code so as both of them work together... This is the PIR Sensor code using Arduino,

 * PIR sensor tester
 */
 
int ledPin = 13;                // choose the pin for the LED
int inputPin = 2;               // choose the input pin (for PIR sensor)
int pirState = LOW;             // we start, assuming no motion detected
int val = 0;                    // variable for reading the pin status
 
void setup() {
  pinMode(ledPin, OUTPUT);      // declare LED as output
  pinMode(inputPin, INPUT);     // declare sensor as input
 
  Serial.begin(9600);
}
 
void loop(){
  val = digitalRead(inputPin);  // read input value
  if (val == HIGH) {            // check if the input is HIGH
    digitalWrite(ledPin, HIGH);  // turn LED ON
    if (pirState == LOW) {
      // we have just turned on
      Serial.println("Motion detected!");
      // We only want to print on the output change, not state
      pirState = HIGH;
    }
  } else {
    digitalWrite(ledPin, LOW); // turn LED OFF
    if (pirState == HIGH){
      // we have just turned of
      Serial.println("Motion ended!");
      // We only want to print on the output change, not state
      pirState = LOW;
    }
  }
}

[nuderobmonkey]

I never have an Arduino programmed with C-code, but at a closer look at your code, merging seems pretty easy:
The pin definitions belong to the pin definitions, the statements inside your setup() function needs to be merged to the setup function, and the statements of the loop() belongs into your other loop.

[salem c]

Rename all the functions to be respectively.
setup_pad()
loop_pad()
setup_pir()
loop_pir()

Then write new setup and loop

void setup() {
    setup_pad();
    setup_pir();
}

void loop() {
    loop_pad();
    loop_pir();
}