====== Using LCD Display ======

An alphanumerical LCD is a straightforward and widely used output device in embedded systems and IoT applications. The LCD used here has a fixed organization of 2 lines and 16 characters per line (2x16).

This scenario guides you through displaying text on the LCD using Arduino.

===== Prerequisites =====
  * Familiarize yourself with Arduino hardware reference.
  * Install the LiquidCrystal library (built-in Arduino library).

===== Hardware Connections =====
| LCD Pin       | Arduino Pin |
|---------------|-------------|
| RS            | 8           |
| EN            | 9           |
| D4            | 4           |
| D5            | 5           |
| D6            | 6           |
| D7            | 7           |
| Buttons Input | A0          |

===== Suggested Knowledge Resources =====
  * Arduino basic programming fundamentals.
  * [[taltech:arduino:hardware|Arduino Uno Hardware Reference]]

===== Task =====
Display the text "Hello World" on the first line and "Hello IoT" on the second line of the LCD.

===== Steps =====

=== Step 1: Include Library ===
Add the LCD library to your Arduino sketch:
<code c>
#include <LiquidCrystal.h>
</code>

=== Step 2: Declare GPIO Pins ===
Define GPIO pins connected to LCD control lines:
<code c>
const int rs = 8, en = 9, d4 = 4, d5 = 5, d6 = 6, d7 = 7;
</code>

=== Step 3: Initialize LCD ===
Create an instance of the LCD:
<code c>
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);
</code>

Set up the display dimensions (2 rows, 16 columns):
<code c>
lcd.begin(16, 2);
</code>

=== Step 4: Display Text ===
Write text to the LCD screen:
<code c>
lcd.setCursor(0, 0); // top left corner
lcd.print("Hello World");

lcd.setCursor(0, 1); // second line
lcd.print("Hello IoT");
</code>

===== Validation =====
The LCD should clearly display "Hello World" on line 1 and "Hello IoT" on line 2.

===== Useful Methods =====
  * ''lcd.clear()'' – clears all text from the LCD.
  * ''lcd.setCursor(col, row)'' – positions the cursor.
  * ''lcd.print(data)'' – prints data to the display.

===== Troubleshooting =====
If the LCD shows incorrect characters or nothing:
  - Double-check wiring and pin assignments.
  - Verify correct initialization (`lcd.begin(16,2)`).
  - Adjust the contrast potentiometer on the LCD, if available.