/* 
 * 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);

byte customChar[] = {
  B00000,
  B00000,
  B00000,
  B00000,
  B00000,
  B00000,
  B00000,
  B11111
};

char numberArray[10];
char arr[10];

char floatStr[10];
char *pointer[] = { "uno", "due",  "pro"};

float val;
int move = 2;
int select = 3;
void setup() {
  // Set up the LCD's number of columns and rows:
  lcd.begin(16, 2);
  // Print Hello World! to the LCD.
  lcd.createChar(0, customChar);
  pinMode(A0,INPUT);
  pinMode(move, INPUT_PULLUP);
  pinMode(select, INPUT_PULLUP);
  
}

unsigned long now,prev = 0;
unsigned long interval = 500;

int i = 0;
int pointer_val = 0;
void loop() {
  val = analogRead(A0) * (5.0/1023.0)*3;
  dtostrf(val, -6, 2, floatStr);  // 6 char min total width, 2 after decimal -. left justified. so -


  //sprintf(numberArray, "%s", floatStr );
  //snprintf(numberArray,  sizeof(numberArray),"%s",  floatStr); // more good.
  now = millis();

  lcd.setCursor(0,0);
  lcd.print("VOLT: ");
  lcd.setCursor(5,0);
  lcd.print(floatStr);

  lcd.setCursor(0,1);
  sprintf(arr, "%s", pointer[i] );
  lcd.print(arr);

    lcd.setCursor(13,0);
    lcd.print(pointer[pointer_val]);

  if(digitalRead(move) == LOW){
    i = i + 1;

    if(i == 3) {i = 0;}
  }
  if(digitalRead(select) == LOW)
  {
    pointer_val = i;
  }
  // if((now-prev) >= interval)
  // {
  //   i = i+1;
  //   if(i == 3) {i = 0;}
  //   prev = now;
  // }
}