countdown?

Projects General Guidance
1

I want to learn to make the countdown time and set the time using the four buttons. "Up, down, select, go back" and 20X4 LCD screen,
My question is what I did the first step to creating a set time?

#include <LiquidCrystal.h>
LiquidCrystal lcd(7,6,5,4,3,2); 
int pin = A0;
int val =0;

void setup(){
  Serial.begin(9600);
  lcd.begin(20,4);
}
void loop(){
}

char ReadKeypad()
{
  val = analogRead(pin);
  Serial.println(val);
  
  if(val >689 && val < 700)
    return 'U';
  else if(val >839 && val < 850)
    return 'D';
  else if(val >450 && val < 500)
    return 'B';
  else if(val >550 && val < 560)
    return 'S';
}
2

it's a start. next step; print to the LCD in addition Serial

3

wg0z:
it's a start. next step; print to the LCD in addition Serial

ok, I add a first look,
What should I do to make a button to show the numbers?
starting from the number 0-60

#include <LiquidCrystal.h>
LiquidCrystal lcd(7,6,5,4,3,2); 
int but_pin = A0;
int val =0;

void setup(){
  Serial.begin(9600);
  lcd.begin(20,4);
  lcd.setCursor(0,0);
  lcd.print("SET COUNTDOWN");
  lcd.setCursor(0,1);
  lcd.print("00:00:00");
}
void loop(){

}

char ReadKeypad()
{
  val = analogRead(but_pin);
  Serial.println(val);
  
  if(val >689 && val < 700)
    return 'U';
  else if(val >839 && val < 850)
    return 'D';
  else if(val >450 && val < 500)
    return 'B';
  else if(val >550 && val < 560)
    return 'S';
}
4

fine. now start using ReadKeypad() and do things based on th retuen value
side note: ReadKeypad should probably return 'none' if and as required; your logic is apparently incomplete

5

wg0z:
fine. now start using ReadKeypad() and do things based on th retuen value
side note: ReadKeypad should probably return 'none' if and as required; your logic is apparently incomplete

sorry, how do it?