Hello guys i want to control the lcd backlight with a push button when i press the button the backlight stays on for 30 sec then it turn of.I'm using a LCD1602 display with an i2c module

if (buttonState == LOW) {
  lcd.backlight();
}
else
  lcd.noBacklight();

Something like this but when i take off my finger from the button the lcd backlight turns off , i want to stay on for 30 sec then turn off.
PS: i don't want to use delay function

 

figuere it out , if someone need the same thing :

if (buttonState == LOW) {
    lcd.clear();
    lcdLightOn_StartMillis = millis();
    currentLcdLightOnTime = 0;
    isLcdLightOn = true;
    lcd.backlight();
  }
    if(isLcdLightOn){
      currentLcdLightOnTime = millis() - lcdLightOn_StartMillis;
      if(currentLcdLightOnTime > LCD_LIGHT_ON_TIME){
        isLcdLightOn = false;
        lcd.noBacklight();
      }
    }

 

HI,

That does not look like the entire set of code there. I take it there is a loop too.