Why doesn't it run on arduino mega2560?

In tinkercad, it was output normally, but in Arduino mega2560, why does the void clock part and stopwatch part blink alternately and the button does not work?

#include <LiquidCrystal.h>;
const int rs = 12, en = 11, d4 = 6, d5 = 5, d6 = 4, d7 = 3;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);

bool isAlarm = false, isStopwatch = false, isTimer = false;
const int led = 13;
const int pushbtn1 = 10; 
const int pushbtn2 = 9;
const int pushbtn3 = 8;
const int pushbtn4 = 7;

int hour=10, minute=15, second=5, pis=0, mls=0, lastTime=0, now;
int hourAlarm=0, minuteAlarm=0, secondAlarm=0;
int mode=0;
int flag = 0, flagAlarm = 0;  //indicates 0 = AM, 1 = PM


int btnstate1; //indicates pushbtn's state
int btnstate2;
int btnstate3;
int btnstate4;


void setup() {
  lcd.begin(16, 2);
  pinMode(pushbtn2, INPUT);
  pinMode(pushbtn3, INPUT);
  pinMode(pushbtn4, INPUT);
  pinMode(pushbtn1, INPUT);
  pinMode(led, OUTPUT);
  Serial.begin(9600);
}

void loop(){
  if(mode==0)clock();
  else if(mode==1)setTime();
  else if(mode==2)setAlarm();
  else if(mode==3)setTimer();
  else if(mode==4)stopwatch();
}


//////////****************CHECKING FOR NEW SCREEN***************//////////
void checkState(){
  btnstate1=digitalRead(pushbtn1);
  btnstate2=digitalRead(pushbtn2);
  btnstate3=digitalRead(pushbtn3);
  btnstate4=digitalRead(pushbtn4);
  if(btnstate1|btnstate2|btnstate3|btnstate4) {
     if(btnstate1==1){
       mode=1;
     }
     if(btnstate2==1){
       mode=2;
     }
     if(btnstate3==1){
       mode=3;
     }
     if(btnstate4==1){
       mode=4;
     }
    }
    else {
       mode=0;
    }
}


//////////****************CLOCK***************//////////
void clock(){
  lcd.setCursor(0,0);
  lcd.print("What time is it?");
  lcd.setCursor(0,1);
  lcd.print("It's ");
  if(hour<10)lcd.print("0");
  lcd.print(hour);
  lcd.print(":");
  if(minute<10)lcd.print("0");
  lcd.print(minute);
  lcd.print(":");
  if(second<10)lcd.print("0");
  lcd.print(second);

 if(flag==0) lcd.print(" AM");
 if(flag==1) lcd.print(" PM");
 
 checkState();
 delay(200);
 runningClock(&hour, &minute, &second, &now, &lastTime, &mls, &flag);
}

void runningClock(int* _hour,int* _minute, int* _second, int* _now, int* _lastTime, int* _mls, int* _flag){
 int increHour=0; 
 *_now=(millis());
 *_mls+=(*_now-*_lastTime);
 *_lastTime=*_now;

 if(*_mls >= 1000){
  *_second+=(*_mls/1000); 
  *_mls%=1000;
  }
 if(*_second >= 60){
   *_minute+=*_second/60;
   *_second%=60;
  }
 if(*_minute >= 60){
   increHour=*_minute/60;
   	*_minute%=60;
  }
  if(increHour%24==0); //hour as before
  else {
    increHour%=24;
    if(increHour<12){
      if(*_hour==12){
        *_hour=increHour;
      }
      else if(*_hour+increHour>=12){
        *_hour-=12;
        *_flag=*_flag==0?1:0;
      }
    }
    else{
      *_hour=((*_hour+increHour)%12);
      *_flag=*_flag==0?1:0;
      
    }
 	if(*_flag==0 & *_hour==12)*_hour=0;
 	else if(*_flag==1 & *_hour==0)*_hour=12;
 }
}



//////////****************TIMESETTING***************//////////
void setTime() {
  int *main_var;
  int X, Y;
  lcd.clear();
  
  int currentChangeIn = 1; //1 is hour 2 is minute and so on
  while(true) 
  {
    lcd.setCursor(0,0);
  	lcd.print("Set Time");
  	lcd.setCursor(0,1);
  	if(hour<10)lcd.print("0");
  	lcd.print(hour);
  	lcd.print(":");
  	if(minute<10)lcd.print("0");
  	lcd.print(minute);
  	lcd.print(":");
  	if(second<10)lcd.print("0");
  	lcd.print(second);

  	if(flag==0) lcd.print(" AM");
  	if(flag==1) lcd.print(" PM");
    
   	btnstate1=digitalRead(pushbtn1);
  	btnstate2=digitalRead(pushbtn2);
  	btnstate3=digitalRead(pushbtn3);
  	btnstate4=digitalRead(pushbtn4);
    if(btnstate1==1){
      mode=0;
      delay(200);
      break;
    }
    if(btnstate3==1){
      if(currentChangeIn==3)currentChangeIn=0;
      currentChangeIn+=1;
      delay(200);
    }
    if(currentChangeIn==1){
      main_var = &hour;
      X = 0;
      Y = 1;
     
      if(digitalRead(pushbtn2)==1){
        hour+=1;
        if(hour==13)hour=1;
        else if(hour==12 & flag==0)hour=0;
        delay(200);
      }
    }
    if(currentChangeIn==2){
      main_var = &minute;
      X = 3;
      Y = 1;
     
      if(digitalRead(pushbtn2)==1){
        minute+=1;
        if(minute==60)minute=0;
        delay(200);
      }
    }
    if(currentChangeIn==3){
      main_var = &second;
      X = 6;
      Y = 1;
     
      if(digitalRead(pushbtn2)==1){
        second+=1;
        if(second==60)second=0;
        delay(200);
      }
    }
    if(btnstate4==1){
      flag=flag==0?1:0;
      if(flag==0 & hour==12)hour=0;
      else if(flag==1 & hour==0)hour=12;
      delay(200);
    }
    blink(*main_var,X,Y);
	runningClock(&hour, &minute, &second, &now, &lastTime, &mls, &flag);
  }
}



//////////****************ALARM***************//////////
void setAlarm() {
  int *main_var;
  int X, Y;
  lcd.clear();
  
  int currentChangeIn = 1; //1 is hour 2 is minute and so on
  while(true) 
  {
    lcd.setCursor(0,0);
  	lcd.print("Set Alarm");
  	lcd.setCursor(0,1);
  	if(hourAlarm<10)lcd.print("0");
  	lcd.print(hourAlarm);
  	lcd.print(":");
  	if(minuteAlarm<10)lcd.print("0");
  	lcd.print(minuteAlarm);
  	lcd.print(":");
  	if(secondAlarm<10)lcd.print("0");
  	lcd.print(secondAlarm);

  	if(flagAlarm==0) lcd.print(" AM");
  	if(flagAlarm==1) lcd.print(" PM");
    
   	btnstate1=digitalRead(pushbtn1);
  	btnstate2=digitalRead(pushbtn2);
  	btnstate3=digitalRead(pushbtn3);
  	btnstate4=digitalRead(pushbtn4);
    if(btnstate1==1){
      mode=0;
      delay(200);
      break;
    }
    if(btnstate3==1){
      if(currentChangeIn==3)currentChangeIn=0;
      currentChangeIn+=1;
      delay(200);
    }
    if(currentChangeIn==1){
      main_var=&hourAlarm;
      X = 0;
      Y = 1;
     
      if(digitalRead(pushbtn2)==1){
        hourAlarm+=1;
        if(hourAlarm==13)hourAlarm=1;
        else if(hourAlarm==12 & flagAlarm==0)hourAlarm=0;
        delay(200);
      }
    }
    if(currentChangeIn==2){
      main_var=&minuteAlarm;
      X = 3;
      Y = 1;
     
      if(digitalRead(pushbtn2)==1){
        minuteAlarm+=1;
        if(minuteAlarm==60)minuteAlarm=0;
        delay(200);
      }
    }
    if(currentChangeIn==3){
      main_var=&secondAlarm;
      X = 6;
      Y = 1;
     
      if(digitalRead(pushbtn2)==1){
        secondAlarm+=1;
        if(secondAlarm==60)secondAlarm=0;
        delay(200);
      }
    }
    if(btnstate4==1){
      flagAlarm=flagAlarm==0?1:0;
      if(flagAlarm==0 & hourAlarm==12)hourAlarm=0;
      else if(flagAlarm==1 & hourAlarm==0)hourAlarm=12;
      delay(200);
    }
    blink(*main_var,X,Y);
  }
  isAlarm=true;
  runningClock(&hour, &minute, &second, &now, &lastTime, &mls, &flag);
}

//////////****************TIMER***************//////////
void setTimer() {
  int minuteTimer=0, secondTimer=0, mlsTimer=0, lastTimeTimer;
  int *main_var;
  int X, Y;
  lcd.clear();
  int brFlag=0; //blinking stopper
  int currentChangeIn = 2; //1 is hour 2 is minute and so on
  while(true) 
  {
    lcd.setCursor(0,0);
  	lcd.print("Set Timer");
  	lcd.setCursor(0,1);
  	if(minuteTimer<10)lcd.print("0");
  	lcd.print(minuteTimer);
  	lcd.print(":");
  	if(secondTimer<10)lcd.print("0");
  	lcd.print(secondTimer);
    
   	btnstate1=digitalRead(pushbtn1);
  	btnstate2=digitalRead(pushbtn2);
  	btnstate3=digitalRead(pushbtn3);
  	btnstate4=digitalRead(pushbtn4);
    if(btnstate1==1){
      mode=0;
      delay(200);
      break;
    }
    if(btnstate3==1){
      currentChangeIn+=1;
      if(currentChangeIn==4)currentChangeIn=2;
      delay(200);
    }
    if(currentChangeIn==2){
      main_var=&minuteTimer;
      X = 0;
      Y = 1;
     
      if(digitalRead(pushbtn2)==1){
        minuteTimer+=1;
        delay(200);
      }
    }
    if(currentChangeIn==3){
      main_var=&secondTimer;
      X = 3;
      Y = 1;
     
      if(digitalRead(pushbtn2)==1){
        secondTimer+=1;
        if(secondTimer==60)secondTimer=0;
        delay(200);
      }
    }
    if(btnstate4==1){
      if(!isTimer)isTimer=true;
      else{
        isTimer=false;
      }
      brFlag=1;
      lastTimeTimer=millis();
      delay(200);
    }
    if(isTimer)runningTimer(&minuteTimer, &secondTimer, &mlsTimer, &lastTimeTimer);
    if(minuteTimer==0&secondTimer==0)brFlag=0;
    if(brFlag==0)blink(*main_var,X,Y);
    delay(200);
    runningClock(&hour, &minute, &second, &now, &lastTime, &mls, &flag);
  }
}

void runningTimer(int* _minute, int* _second, int* _mls, int* _lastTime){
 int _now=millis();
 *_mls+=(_now-*_lastTime);
 *_lastTime=_now;
 if(*_mls >= 1000){
  *_second-=(*_mls/1000); 
  *_mls%=1000;
  }
 if(*_second <= 0){
   if(*_minute == 0 & *_second < 0){
   	isTimer=false;
   	digitalWrite(led, HIGH);
   	delay(3000);
   	digitalWrite(led, LOW);
    *_second=0;
  }
   else if(*_minute>0){
    *_minute-=1;
   	*_second=59;
   }
 }
}



//////////****************STOPWATCH***************//////////
void stopwatch(){
  int hourStopwatch=0, minuteStopwatch=0, secondStopwatch=0, mlsStopwatch=0, lastTimeStopwatch=0;
  lcd.clear();
  
  while(true) 
  {
    lcd.setCursor(0,0);
  	lcd.print("Stopwatch");
  	lcd.setCursor(0,1);
  	if(hourStopwatch<10)lcd.print("0");
  	lcd.print(hourStopwatch);
  	lcd.print(":");
  	if(minuteStopwatch<10)lcd.print("0");
  	lcd.print(minuteStopwatch);
  	lcd.print(":");
  	if(secondStopwatch<10)lcd.print("0");
  	lcd.print(secondStopwatch);
    
   	btnstate1=digitalRead(pushbtn1);
  	btnstate2=digitalRead(pushbtn2);
  	btnstate3=digitalRead(pushbtn3);
  	btnstate4=digitalRead(pushbtn4);
    if(btnstate1==1){
      mode=0;
      delay(200);
      break;
    }
    if(btnstate2==1){
      isStopwatch=true;
      lastTimeStopwatch=millis();
      delay(200);
    }
    if(btnstate3==1){
      isStopwatch=false;
      delay(200);
    }
    if(btnstate4==1){
      isStopwatch=false;
   	  hourStopwatch=0;
      minuteStopwatch=0;
      secondStopwatch=0;
      delay(200);
    }
    if(isStopwatch)runningStopwatch(&hourStopwatch, &minuteStopwatch, &secondStopwatch, &lastTimeStopwatch, &mlsStopwatch);
 	runningClock(&hour, &minute, &second, &now, &lastTime, &mls, &flag);
  }
}

void runningStopwatch(int* _hour,int* _minute, int* _second, int* _lastTime, int* _mls){
 int increHour=0, _now; 
 _now=(millis());
 *_mls+=(_now-*_lastTime);
 *_lastTime=_now;

 if(*_mls >= 1000){
  *_second+=(*_mls/1000); 
  *_mls%=1000;
  }
 if(*_second >= 60){
   *_minute+=*_second/60;
   *_second%=60;
  }
 if(*_minute >= 60){
   *_hour=*_minute/60;
   	*_minute%=60;
  }
  if(*_hour>=12){
    isStopwatch=false;
  }
}


//////////****************COMMON FUNCTION***************//////////
void blink(int main_var, int X, int Y){
  lcd.setCursor(X, Y);
  	if(pis == 0){ 
  	  if(main_var<10)lcd.print("0");
  	  lcd.print(main_var);
  	  delay(200);
  	}
  	if(pis == 1){
 	  lcd.print("  ");
 	  delay(200);
    }
  	pis=(pis+1)%2;
}

//////////****************THANK YOU***************//////////

How are your buttons connected? Did you attach pulldown resistors to your button pins?
Tinkercad is not real life :wink:

In reality, unlike the picture above, it is connected without a resistor.

Will connecting a resistor solve it?

Your switches are upside down logically.

You have logic that suggests they are normally 0 (LOW), and when pressed yield a 1 (HIGH).

I wired them as pulled-down INPUTs, and the buttons pull up the pin. That's what you have to do to get "true" readings from the buttons - pressed = 1, not = 0.

I would normally just have inverted the digitalRead at the very point it was done

!digitalRead(BUTTONX);

with the '!', so all interpretation would be flipped, but you had them scattered all over, so I did the fix in hardware.

BTW very nice clock!

I see quite a few delay() calls in you code. This looks like an attempt to tame the pushbuttons, and seems effective. This is not, however, the best way to go.

You should look into button handling including state change detection and debouncing. It will make your code more something, at the very least easier to read, understand and modify or enhance.

Added : yes, your buttons are very finicky due to the way you handle them. It takes a bit of practice to be on the button just right… even sustituting wokwi.com's "bouvnceless" pushbuttons did not help. So this is where you should focus on improvments.

a7

If you don't have a pulldown resistor, then your input is floating when the button is not pressed. Your readings are random an you don't get a stable value.

@slthdwnsl could you post a little user manual?

Of course we could read all your code and figure out the functions and how the buttons (are supposed to) work… easier if you just say, then we might be able to help you fix it up a but.

a7