Thanks for clearing it up man! I really appreciate your help!
Maybe I'm doing it the other way as you do, but your explanation of it helps me a lot.
While I was stuck with the 'true' error, I tried to code it on my way.
Everything works fine, unless the countdown:
So first off all, I need to enter the setup password, it that is correct, then I need to set the countdown time.
If I've set the countdown time(for example 120(seconds)), and I press '#' on the keypad, then the time is set and I need to enter the arm code.
If I've entered the arm code, then the countdown starts, but with problems: it wont countdown for the countdown value I set before. It just countdown from the number of keys I've pressed. So for 120 it will countdown from 3 to 0, because 120 has 3 numbers. For 1200 it will countdown from 4 to 0, because 1200 has 4 numbers, from 12 it will countdown from 2 to 0,...and so forth.
I think there is something wrong in my code, but I don't see what. Maybe you can see what's wrong?
Probably it is wrong in the arrays(TimeValue or inputTimeArray), the Countdown function or the SetTimeCode.
Again, thanks for helping me. 
#include <LiquidCrystal.h>
#include <ShiftLCD.h> // Include Library's
#include <Keypad.h>
#define SETUP 0
#define SETTIME 1 // case for setting time
#define ARMCODE 2 // case for arming bomb
#define ARMED 3 // case for countdown
#define DISARMED 4 // case for stopping countdown
#define DETONATED 5 // case for finished countdown
int bombState=0; // 0 = Setup, 1 = Set time, 2 = Arm Code, 3 = Armed ,4 = Disarmed, 5 = Detonated
int time;
int setTime;
const byte ROWS = 4; // Keypad has 4 rows
const byte COLS = 4; // Keypad has 4 columns
char keys[ROWS][COLS] = {
{'1','2','3','A'},
{'4','5','6','B'}, // define which character is on a button
{'7','8','9','C'},
{'*','0','#','D'}
};
byte rowPins[ROWS] = {5,6,7,8}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {9,10,11,12}; //connect to the column pinouts of the keypad
Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );
ShiftLCD lcd(2, 4, 3); // pins connected to LCD
char clearButton[1] = {'*'};
char EnterButton[1] = {'#'};
char SetupPW[] = {'1','2','3','4'};
char TimeValue[4];
char ArmCode[4] = {'7','8','9','1'}; // password to arm the bomb
char inputTimeArray[4]; // array to gather user keypad presses
char inputSetupArray[4];
char inputArmArray[4];
int i = 0; // store keypresses here
int x = 0; // store the keypresses here
int a = 0;
void setup()
{
lcd.begin(16,2); // open the LCD
// bootup screen
lcd.print("AIRSOFT BOMB V1"); // print some text
lcd.setCursor(4,1);
lcd.print("BY TIBO");
delay(2500); // display text for 2500ms
lcd.clear(); // clear display
}
void loop()
{
// cases
switch(bombState) {
////////////// SET COUNTDOWN TIME//////////////////////////
case SETUP:
{
SetupCode();
}
break;
case SETTIME: // set the countdown time
{
SetTimeCode();
}
break;
case ARMCODE: // enter the right code to arm the bomb
{
TypeArmCode();
}
break;
case ARMED:
{
Countdown();
}
break;
}
}
////////////////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////SetupCode//////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////
boolean SetupCode() {
lcd.setCursor(0,0);
lcd.print("Enter Password:");
char key = keypad.getKey();
//if a key is pressed
if(key)
{
inputSetupArray[x] = key; //store entry into array
x++;
lcd.setCursor(0,1); // set cursor at column 0 and row 1
lcd.print(key); // print keypad character entry to lcd
if (x == 4) // if 4 presses on the keypad have been made
{
if (inputSetupArray[0] == SetupPW[0] && // if first character pressed on keypad = first character in password for arming bomb
inputSetupArray[1] == SetupPW[1] && // and if second character pressed on keypad = second character in password for arming bomb
inputSetupArray[2] == SetupPW[2] && // and if third character pressed on keypad = third character in password for arming bomb
inputSetupArray[3] == SetupPW[3] ) // and if fourth charactet pressed on keypad = fourth character in password for arming bomb
{
lcd.clear(); // clear display
lcd.setCursor(0,0);
lcd.print("Pass Correct"); // display some text
delay(1000); // display text for 1000ms
lcd.clear();
bombState = SETTIME; // switch to ARMED case
}
else {
lcd.clear(); // clear display
lcd.setCursor(0,0);
lcd.print("Pass Incorrect"); // display some text
delay(1000); // display text for 1000ms
x = 0; //Reset your entryindex so that it effectively clears your entry.
inputSetupArray[x] = '/0'; //Always add the null
lcd.clear();
}
}
}
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////SetTimeCode//////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
boolean SetTimeCode() {
lcd.setCursor(0,0);
lcd.print("Enter Time:");
char key = keypad.getKey();
//if a key is pressed
if(key)
{
inputTimeArray[i] = key; //store entry into array
i++;
inputTimeArray[i] = '/0';
lcd.setCursor(0,1); // set cursor at column 0 and row 1
lcd.print(key); // print keypad character entry to lcd
if (key == '#') {
inputTimeArray[i] = TimeValue[i];
lcd.clear(); // clear display
lcd.setCursor(0,0);
lcd.print("Time Set"); // display some text
delay(1000); // display text for 1000ms
bombState = ARMCODE; // switch to ARMED case
lcd.clear();
}
}
}
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////TypeArmCode////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
boolean TypeArmCode() {
lcd.setCursor(0,0);
lcd.print("Enter ArmCode:");
char key = keypad.getKey();
//if a key is pressed
if(key)
{
inputArmArray[a] = key; //store entry into array
a++;
lcd.setCursor(0,1); // set cursor at column 0 and row 1
lcd.print(key); // print keypad character entry to lcd
if (a == 4) // if 4 presses on the keypad have been made
{
if (inputArmArray[0] == ArmCode[0] && // if first character pressed on keypad = first character in password for arming bomb
inputArmArray[1] == ArmCode[1] && // and if second character pressed on keypad = second character in password for arming bomb
inputArmArray[2] == ArmCode[2] && // and if third character pressed on keypad = third character in password for arming bomb
inputArmArray[3] == ArmCode[3] ) // and if fourth charactet pressed on keypad = fourth character in password for arming bomb
{
lcd.clear(); // clear display
lcd.setCursor(0,0);
lcd.print("Bomb Armed!"); // display some text
delay(1000); // display text for 1000ms
lcd.clear();
bombState = ARMED; // switch to ARMED case
}
else {
lcd.clear(); // clear display
lcd.setCursor(0,0);
lcd.print("Code Incorrect"); // display some text
delay(1000); // display text for 1000ms
a = 0; //Reset your entryindex so that it effectively clears your entry.
inputSetupArray[a] = '/0'; //Always add the null
lcd.clear();
}
}
}
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////Countdown/////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
boolean Countdown() {
while(i > 0) {
lcd.setCursor(0,0);
lcd.print("Time remaining:");
i -= 1;
delay(1000);
lcd.clear();
lcd.setCursor(7,1);
lcd.print(i);
if (i == 0) {
lcd.clear();
lcd.setCursor(0,0);
lcd.print("Bomb Exploded");
}
}
}