I must admit that I'm not a fan of programming a microcontroller in the same sequential way like a PET2001 or CBM64 back in the good old 70/80th ... 
If you are interested in a different way to handle your application feel free to have a look here:
https://wokwi.com/projects/391797529307245569
Sketch:
/*
Forum: https://forum.arduino.cc/t/the-lcd-screen-doesnt-show-the-input-from-the-keypad/1232826
Wokwi: https://wokwi.com/projects/391797529307245569
*/
#include <LiquidCrystal.h>
#include <Keypad.h>
// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(8, 9, 10, 11, 12, 13);
const byte ROWS = 4; //four rows
const byte COLS = 4; //four columns
int button = A5;
int board = A3;
//define the symbols on the buttons of the keypads
char timeobj;
char keys[ROWS][COLS] = {
{'1', '2', '3', 'A'},
{'4', '5', '6', 'B'},
{'7', '8', '9', 'C'},
{'*', '0', '#', 'D'}
};
byte rowPins[ROWS] = {7, 6, 5, 4}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {3, 2, 1, 0}; //connect to the column pinouts of the keypad
enum StatusType { INPUTCODE, INPUTTEMPO, GUESSCODE, SOLVED, HACKED, FAILED, WAIT};
StatusType status;
unsigned long codiceSegreto = 0;
String inputString;
int tempoTimer = 0;
int countDown = 0;
bool codiceInserito = false;
unsigned long startTime;
unsigned long countDownTime;
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);
char key;
void setup() {
lcd.begin(16, 2);
pinMode(board, INPUT);
pinMode(button, INPUT_PULLUP);
setNewStatus(INPUTCODE);
}
void loop() {
handleKeypad();
handleTimer();
handleHacking();
StateMachine();
}
void handleKeypad() {
key = keypad.getKey();
}
void StateMachine() {
switch (status) {
case INPUTCODE:
handleCodeInput();
break;
case INPUTTEMPO:
handleTempoInput();
break;
case GUESSCODE:
guessCode();
break;
case SOLVED:
solved();
break;
case HACKED:
handleHacked();
break;
case FAILED:
failed();
break;
case WAIT:
handleWait();
break;
}
}
void handleWait() {
if (key == 'A') {
setNewStatus(GUESSCODE);
}
if (key == 'D') {
setNewStatus(INPUTCODE);
}
}
void setNewStatus(StatusType newStatus) {
inputString = "";
switch (newStatus) {
case INPUTCODE:
clearLCD("Inserisci codice:");
break;
case SOLVED:
codiceInserito = false;
break;
case FAILED:
codiceInserito = false;
startTime = millis();
break;
case GUESSCODE:
lcd.clear();
codiceInserito = true;
countDownTime = millis();
countDown = tempoTimer + 1;
break;
case WAIT:
clearLCD("Again with 'A'", "New with 'D'");
break;
}
status = newStatus;
}
void clearLCD(String line) {
lcd.clear();
lcd.print(line);
}
void clearLCD(String line0, String line1) {
clearLCD(line0);
lcd.setCursor(0, 1);
lcd.print(line1);
}
boolean keyIsNumber() {
return (key >= '0' && key <= '9');
}
void addNumberToInputString(int maxLen) {
if (keyIsNumber() && inputString.length() < maxLen) {
inputString += key;
lcd.setCursor(0, 1);
lcd.print(inputString);
}
}
void handleCodeInput() {
addNumberToInputString(8);
if (key == '#' && inputString.length() >= 3) { // Use in minimum three numbers
codiceSegreto = inputString.toInt();
clearLCD("Inserisci tempo:");
setNewStatus(INPUTTEMPO);
}
}
void handleTempoInput() {
addNumberToInputString(2);
if (key == '*' && inputString.toInt() >= 5) { // Give in minimum five seconds
tempoTimer = inputString.toInt();
clearLCD("Codice e tempo", "inseriti!");
delay(2000);
setNewStatus(GUESSCODE);
}
}
void guessCode() {
addNumberToInputString(8);
if (key == 'C') {
unsigned long guess = inputString.toInt();
codiceInserito = false;
if (guess == codiceSegreto) {
setNewStatus(SOLVED);
} else {
setNewStatus(FAILED);
}
}
}
void failed() {
lcd.clear();
lcd.print("Ordigno detonato");
if (millis() - startTime > 3000 ) {
clearLCD("Out of business ...");
delay(10000);
setNewStatus(WAIT);
}
}
void solved() {
clearLCD("ordigno","disinnescato");
delay(3000);
setNewStatus(WAIT);
}
void handleHacked() {
clearLCD("Hacking ....");
delay(1000);
setNewStatus(SOLVED);
}
void handleTimer() {
static unsigned long lastCountDown = 0;
if (codiceInserito && countDown > 0) {
if (lastCountDown == 0) {
lastCountDown = millis();
}
if (millis() - lastCountDown > 1000) {
lastCountDown = millis();
countDown--;
lcd.setCursor(0, 0);
lcd.print("Count Down: ");
lcd.setCursor(12, 0);
lcd.print(countDown);
}
if (countDown == 0) {
setNewStatus(FAILED);
}
} else {
lastCountDown = 0;
}
}
void handleHacking() {
if (!codiceInserito) {
return;
}
if (digitalRead(button) == LOW ||
digitalRead(board) == HIGH) {
setNewStatus(HACKED);
}
}
The sketch uses your original wiring but a state machine to switch between different states of your application:
-
INPUTCODE
-
INPUTTEMPO
-
GUESSCODE
-
SOLVED
-
HACKED
-
FAILED
-
WAIT
-
Some states can only be left by a given key input, some change state after a certain time.
-
The secret code requires in minimum three numbers,
-
The tempoTimer requires in minimum five seconds,
-
Hacking is only possible while a valid secret code is active. There are two buttons in Wokwi (the red one "simulates" the external Arduino board pin).
-
A handleTimer() routine takes care of the count down after input of a valid secret code and tempoTimer value.
-
In WAIT state you can choose whether you go for another turn with the same or if you want to input new data.
As each state has its own routine and the preparation before entering a certain state is done in the function setNewStatus().
If you are not happy with one or the other function do not hesitate to change its behaviour.
Be aware that I changed the secret code variables (e.g. codiceSegreto) to unsigned long to handle 8 digits ...
Hope it is of assistance ...
Good luck and have fun!
ec2021
