ShiftLcd Library for Arduino

This Arduino library provides an easy-to-use interface for controlling an HD44780U (or similar) LCD display with a SN74HC595 (or similar) shift register. It can control the display with only four pins from the Arduino.

Table of Contents

• Features
• Wiring
• Installation
• Usage
• Interface

Features

• Display text on an LCD screen.
• Scroll text left or right with customizable delays.
• Blink the display with a specified blink rate.
• Clear the display for a clean slate.
• See the interface section for all features.

Wiring

1. Connect everything according to the picture:
   • The pull down resistor connected to the LCDs D7-pin should be ca 10 kOhms.
   • The 10 kOhms potentiometer connected to the LCDs V0-pin can be replaced by a ca 5 kOhms resistor.

Installation

Installation can be done either from the Arduino IDE or from the source code.

Arduino IDE:

1. Go to: Sketch > Include Library > Manage Libraries.
2. Search after "ShiftLcd".
3. Click install.

From source:

1. Clone the repository to your projects directory.

   cd <directoryOfProject>
   git clone https://github.com/eb1992/ShiftLcd

2. Import the library via relative path instead:

   
   #include "ShiftLcd/src/ShiftLcd.h"

## Usage

1. Include the `ShiftLcd` library in your Arduino sketch and create an instance of it:

```cpp
  #include <ShiftLcd.h>

  int LCD_EN = 2;
  int LCD_D7 = 3; 
  int SHIFT_SER = 4; 
  int SHIFT_SRCLK = 5;

  ShiftLcd lcd(LCD_EN, LCD_D7, SHIFT_SER, SHIFT_SRCLK);

2. Initialize the LCD in the setup() function and write a message:

  void setup() {
    lcd.begin();
    lcd.write("Hello, World!");
  }

3. Use the library functions to control the LCD in the loop() function:

  void loop() {
    lcd.scrollLeft();
  }

Interface

Constructor. Initializes the LCD with specified pin numbers:

  ShiftLcd(int LCD_EN, int LCD_D7, int SHIFT_SER, int SHIFT_SRCLK);

Methods for LCD control

Initialize the LCD:

  void begin();  

Turn on the LCD:

  void on();     

Turn off the LCD:

  void off();    

Shift the display text one step to the left:

  void shiftLeft();   

Shift the display text one step to the right:

  void shiftRight();  

Scroll text to the right:

  void scrollRight(unsigned long delay);  

Scroll text to the right with the default time:

  void scrollRight();                     

Scroll text to the left:

  void scrollLeft(unsigned long delay);   

Scroll text to the left with the default time:

  void scrollLeft();                      

Blink the display:

  void blink(unsigned long delay);       

Blink the display with the default time:

  void blink();                           

Clear the LCD display:

  void clear();                           

Methods for writing to the LCD

Write a character array:

  void write(char msg[]);                   

Write two character arrays to the two rows of the display:

  void write(char msg1[], char msg2[]);      

Write a character array and an integer to the two rows of the display:

  void write(char msg[], int n);            

Write an integer:

  void write(int n);                        

Write a String:

  void write(String msg);                   

Write two Strings to the two rows of the display:

  void write(String msg1, String msg2);     

Write a String and an integer to the two rows of the display:

  void write(String msg, int n);