Change code to work with 20x4 LCD instead of 16x2

Projects Programming
24

Try this

 lcd.setCursor(x, 1); // draw first (top) row Left
    if (peaks[x] == 0) {
      lcd.setCursor(x, 1);
      lcd.print("_");  // empty
      lcd.setCursor(x, 0);
      lcd.print("_");  // empty
    }
    else {
    if (peaks[x]>4) {       //after value 8 you need to jump to next row, correct ?
     lcd.setCursor(x, 1);
     lcd.write(8);
     lcd.setCursor(x, 0);  
     lcd.write(2*(peaks[x]-4));
    }
    else {       //if not bigger we only occupy 1 row, correct ?
     lcd.setCursor(x, 1); //position inferior row
     lcd.write(2*peaks[x]);
     lcd.setCursor(x, 0);  // position superior row
     lcd.print("_");  //empty 

    }
    }