/* 
 * This is how to write a block comment.
 *
 * Not all LCD displays are the same, 
 * maybe this matches your 16 x 2 LCD.
 * I have the display that is in this video.
 * https://www.youtube.com/watch?v=4BaDaGTUgIY
 *
 * This is where you can get more information
 * http://www.arduino.cc/en/Tutorial/LiquidCrystal
 * 
 * Library originally added 18 Apr 2008	 
 * by David A. Mellis	 
 * library modified 5 Jul 2009	 
 * by Limor Fried (http://www.ladyada.net)	 
 * example added 9 Jul 2009	 
 * by Tom Igoe	 
 * modified 22 Nov 2010	 
 * by Tom Igoe	 
 * modified 7 Nov 2016	 
 * by Arturo Guadalupi	
 * modified 30 Jan 2022
 * by Edoctoor
 *
 * https://wokwi.com/arduino/projects/321995158308520530
 *
 * This example code is in the public domain.	
 * http://www.arduino.cc/en/Tutorial/LiquidCrystalHelloWorld
 *
 */


// include the LiquidCrystal.h library 
#include <LiquidCrystal.h>

/*
 * initialize the library with the interface pins values
 * First create the variables and assign the values
 * because LiquidCrystal lcd(7, 6, 12, 10, 9, 8);
 * will not tell you what wire goes where.
 *
 * TIP: Do the GND and POWER wires after you have made
 * all other connections and you have checked your 
 * schematic several times.
 * 
 * Connect the LCD wires to the pins on the Arduino
 * 
 * Pin LCD Descriptions:
 * Pin 1 --- Ground
 * Pin 2 --- VDD Power for the LCD
 * Pin 3 --- Contrast Adjust
 * Pin 4 --- Register Select (RS)
 * Pin 5 --- Read / Write select (R/W)
 * Pin 6 --- Enable (E)
 * Pin 7 --- not used
 * Pin 8 --- not used
 * Pin 9 --- not used
 * Pin 10 -- not used
 * Pin 11 -- Data line (D4) 4-bits at a time
 * Pin 12 -- Data line (D5) 4-bits at a time
 * Pin 13 -- Data line (D6) 4-bits at a time
 * Pin 14 -- Data line (D7) 4-bits at a time
 * Pin 15 -- Backlight Power
 * Pin 16 -- Backlight Ground (GND) remember 220 ohms resistor
 * 
 */
                    // Double slash for adding single line comments
const int rs = 7;   // Pin 7  on Arduino to pin 4  (RS) on LCD
const int en = 6;   // Pin 6  on Arduino to pin 6  (E)  on LCD
const int d4 = 12;  // Pin 12 on Arduino to pin 11 (D4) on LCD
const int d5 = 10;  // Pin 10 on Arduino to pin 12 (D5) on LCD
const int d6 = 9;   // Pin 9  on Arduino to pin 13 (D6) on LCD
const int d7 = 8;   // Pin 8  on Arduino to pin 14 (D7) on LCD

/* 
  10k potentiometer 
  Connect swipe pin of the potentiometer to the VO pin on the 16 x 2 LCD

  Lastly the Ground (Black) and power wires (Red) 
  from the Arduino to the following pins on the LCD display

  GND   = VSS, RW, and (K with 220 ohms) 
  POWER = VDD, A
 */

LiquidCrystal lcd(rs, en, d4, d5, d6, d7);

void setup() {
  // Set up the LCD's number of columns and rows:
  lcd.begin(16, 2);
  // Print Hello World! to the LCD.
  lcd.print("Hello World!");
}

void loop() {
  // The location of line one is 0
  // The location of line two is 1
  // set the cursor to column 0, line 1 the print the second line
  lcd.setCursor(0, 1);
  lcd.print("Seconds ");
  lcd.print(millis() / 1000);
}