Hello all! I just finished my first "all-me" project. It's a digital combination lock. Easily crackable, and super simple. I wanted to go into this all on my own (not referring to tutorials or other projects) using only what I can recall from throughout my endeavours. It incorporates 5 tactile buttons, an LCD screen from Adafruit, a servo, two LEDs, and of course, the Uno. The code is below, followed by a pic. Comments most definitely welcome! The code is very messy (I'm sure there are dozens of other ways to do it) but I'm still a rookie/n00b, so suggestions and tips are also welcome 
(I'm a fan of constructive criticism!).
#include <Servo.h>
#include <LiquidCrystal.h>
LiquidCrystal lcd(2,3,4,5,6,7);
Servo myservo;
const int button1 = 8;
const int button2 = 9;
const int button3 = 10;
const int button4 = 11;
const int button5 = 12;
int count1 = 0;
int count2 = 0;
int count3 = 0;
int count4 = 0;
int count5 = 0;
int state1 = 0;
int state2 = 0;
int state3 = 0;
int state4 = 0;
int state5 = 0;
int prev1 = 0;
int prev2 = 0;
int prev3 = 0;
int prev4 = 0;
int prev5 = 0;
int totalcount = 0;
int rows = 0;
int red = A0;
int green = A1;
void setup(){
pinMode(button1, INPUT);
pinMode(button2, INPUT);
pinMode(button3, INPUT);
pinMode(red, OUTPUT);
pinMode(green, OUTPUT);
lcd.begin(16,2);
lcd.setCursor(0,0);
lcd.print(" :ENTER CODE: ");
Serial.begin(9600); // For debug. Visually see the button presses.
myservo.attach(13);
myservo.write(0);
}
void loop(){
state1 = digitalRead(button1);
state2 = digitalRead(button2);
state3 = digitalRead(button3);
state4 = digitalRead(button4);
state5 = digitalRead(button5);
if (state1 != prev1){
delay(10);
if (state1 == HIGH){
count1++;
}
else{}
}
if (state2 != prev2){
delay(10);
if (state2 == HIGH){
count2++;
}
else{}
}
if (state3 != prev3){
delay(10);
if (state3 == HIGH){
count3++;
}
else{}
}
if (state4 != prev4){
delay(10);
if (state4 == HIGH){
count4++;
}
else{}
}
if (state5 != prev5){
delay(10);
if (state5 == HIGH){
count5++;
}
else{}
}
prev1 = state1;
prev2 = state2;
prev3 = state3;
prev4 = state4;
prev5 = state5;
totalcount = count1 + count2 + count3 + count4 + count5;
for (rows = 0; rows < totalcount; rows+1){
lcd.setCursor(rows,1);
lcd.print("*");
rows++;
}
if (totalcount == 5){
if (count1 == 2 && count2 == 0 && count3 == 1 && count4 == 2 && count5 == 0){
lcd.clear();
lcd.print(" CODE ACCEPTED ");
myservo.write(90);
digitalWrite(green, HIGH);
digitalWrite(red, LOW);
count1 = 0;
count2 = 0;
count3 = 0;
count4 = 0;
count5 = 0;
totalcount = 0;
delay(10000);
lcd.clear();
lcd.setCursor(0,0);
lcd.print(" :ENTER CODE: ");
myservo.write(0);
digitalWrite(green, LOW);
}
else if (count1 != 2 && count2 != 0 && count3 != 1 && count4 != 2 && count5 != 0 && totalcount == 5){
lcd.clear();
lcd.setCursor(0,0);
lcd.print(" CODE REJECTED ");
digitalWrite(red, HIGH);
digitalWrite(green, LOW);
count1 = 0;
count2 = 0;
count3 = 0;
count4 = 0;
count5 = 0;
totalcount = 0;
delay(5000);
lcd.clear();
lcd.setCursor(0,0);
lcd.print(" :ENTER CODE: ");
digitalWrite(red, LOW);
}
else if (count1 > 2 && count2 > 0 && count3 > 1 && count4 > 2 && count5 > 0 || totalcount == 5){
lcd.clear();
lcd.setCursor(0,0);
lcd.print(" CODE REJECTED ");
digitalWrite(red, HIGH);
digitalWrite(green, LOW);
count1 = 0;
count2 = 0;
count3 = 0;
count4 = 0;
count5 = 0;
totalcount = 0;
delay(5000);
lcd.clear();
lcd.setCursor(0,0);
lcd.print(" :ENTER CODE: ");
digitalWrite(red, LOW);
}
}
Serial.print("1=");
Serial.print(count1);
Serial.print(" 2=");
Serial.print(count2);
Serial.print(" 3=");
Serial.println(count3);
}
