What is LCD Display Arduino?

 

 

 

What is an Arduino?

  • – Arduino is an open-source platform used for building electronics projects. Arduino consists of both a physical programmable microcontroller and a piece of software, or IDE (Integrated Development Environment) that runs on your computer, used to write and upload computer code to the physical board.

 

  • – The Arduino platform unlike most previous programmable circuit boards, the Arduino does not need a separate programmer to load new code onto the board — you can simply use a USB cable. Additionally, the Arduino IDE uses a simplified version of C++, making it easier to learn to program. 

 

  • Arduino provides a standard form factor that breaks out the functions of the micro-controller into a more accessible package.

 

    Arduino Advantages

  • – Low cost: Micro for $15 to more powerful 32-bit development boards for less than $80.

 

  • – Cross platform running: Arduino software can run in Windows, OSX and Linux operating systems.

 

  • – Simple programming environment:  Easy for beginners to use and also flexible for advanced users.

 

  • – The open sources and extensible language: Arduino IDE is based on open source tool. The programming language used can be extended through the C++ library.

 

  • – The open source and expandable hardware: Arduino is based on Atmel’s ATMEGA 8-bit microcontrollers and its SAM3X8E and SAMD21 32-bit microcontrollers. Development boards and modules are planned to be released under the premise of following the “Creative Commons License Agreement”, so experienced circuit designers can make their own modules and carry out corresponding expansions and improvements. Even users who are relatively inexperienced can make a trial version of the basic Uno development board, which is easy to understand the principle of its operation and save costs.

 

  • – The Arduino hardware and software were designed for artists, designers, hobbyists, hackers, newbies, and anyone interested in creating interactive objects or environments. Arduino can interact with buttons, LEDs, motors, speakers, GPS units, cameras, the internet, and even your smart-phone or your TV.

 

The Types of Arduino

  • Arduino Uno:  The Uno is a great choice for your first Arduino.

 

  • LilyPad Arduino: used for wearable e-textile.

 

  • Arduino Mega: The Arduino Mega is like the UNO’s big brother. It has lots (54!) of digital input/output pins.

 

  • Arduino Leonardo: Arduino’s first development board to use one microcontroller with built-in USB. It is cheaper and simpler. The code libraries allow the board to emulate a computer keyboard, mouse, and more.

 

 

 

What is LCD Display Arduino?

LCD means liquid crystal display. Basically, any displays can be used with Arduino, including alphanumeric character LCD display, monochrome graphic LCD display, color TFT LCD display, IPS LCD display. It can also be used for non LCD displays like: PMOLED display, AMOLED display, E-ink (E-paper) displays.  Orient Display developed easy interface (SPI, I2C) displays which can be easily used with Arduino. 

What is the use of LCD display?

LCD displays were first used for watches and calculators.  Now, LCD display technology dominants the display world, it can be found in wearables, smart homes, mobile phones, TVs, laptops, monitors, kiosks, aircraft cockpit, digital cameras, lab instrument, power grid etc.

 

What is LCD display Module?

LCD itself can emit light itself. It has to utilize outside light sources. LCD display module normally includes LCD glass (or LCD panel), LCD driving circuitry ( can be COG, COB or TAB) and a backlight.

 

What is LCD display 16×2?

A LCD display 16*2 is actually a basic and simple to use LCD module. It includes LCD glass, COB (Chip on PCB Board) LCD control board, backlight, zebra to connect LCD glass and control board and a bezel to hold everything together.  16×2 LCD display can display 16 characters per line and there are two lines. Each character has 5×7 dot matrix pixels and the cursor underneath. All 16×2 LCD display originally used standard Hitachi HD44780 driver. Of course the legendary HD44780 controller had EOL long time ago. All the 16×2 LCD displays use HD44780 compatible LCD controllers. Some of them are drop replacement, some of them need to modify the initialization code a little.

 

 

16×2 LCD display pinout definition:

Pin1 (Ground/Source Pin): This is a GND pin of display, used to connect the GND terminal of the microcontroller unit or power source.

Pin2 (VCC/Source Pin): This is the voltage supply pin of the display, used to connect the supply pin of the power source.

Pin3 (V0/VEE/Control Pin): This pin regulates the difference of the display, used to connect a changeable POT that can supply 0 to 5V.

Pin4 (RS pin or Register Select/Control Pin): This pin toggles among command or data register, used to connect a microcontroller unit pin and obtains either 0 or 1(0 = data mode, and 1 = command mode).

Pin5 (Read/Write/Control Pin): This pin toggles the display among the read or writes operation, and it is connected to a microcontroller unit pin to get either 0 or 1 (0 = Write Operation, and 1 = Read Operation).

Pin 6 (Enable pin/Control Pin): This pin should be held high to execute Read/Write process, and it is connected to the microcontroller unit & constantly held high.

Pins 7-14 (Data Pins): These pins are used to send data to the display. These pins are connected in two-wire modes like 4-bit mode and 8-bit mode. In 4-wire mode, only four pins are connected to the microcontroller unit like 0 to 3, whereas in 8-wire mode, 8-pins are connected to microcontroller unit like 0 to 7.

Pin15 (+ve, or A pin or LED backlight anode pin): This pin is connected to +5V power supply.

Pin 16 (-ve, or K pin or LED backlight cathode pin): This pin is connected to GND.

 

  • 16×2 LCD display register

A 16×2 LCD has two registers like data register and command register. The RS (register select) is mainly used to change from one register to another. When the register set is ‘0’, then it is known as command register. Similarly, when the register set is ‘1’, then it is known as data register.

Command Register: The main function of the command register is to store the instructions of command which are given to the display. So that predefined tasks can be performed such as clearing the display, initializing, set the cursor place, and display control. Here commands processing can occur within the register.

Data Register: The main function of the data register is to store the information which is to be exhibited on the LCD screen. Here, the ASCII value of the character is the information which is to be exhibited on the screen of LCD. Whenever we send the information to LCD, it transmits to the data register, and then the process will be starting there. When register set =1, then the data register will be selected.

 

  • LCD Commands

 

16×2 LCD Display Arduino

Hardware Required:

  • Arduino Board
  • LCD Screen (compatible with Hitachi HD44780 driver)
  • pin header to solder to the LCD display pins as a connector
  • 10k ohm potentiometer
  • 220 ohm resistor
  • hook-up wires
  • breadboard

Connection LCD to Arduino (Be sure to check the datasheet or look for labels on your particular LCD)

Or with schematic

The resistor in the diagram above sets the LED backlight brightness. A typical value is 220 Ohms resistor, but other values will work too. Smaller resistors will make the backlight brighter. The potentiometer is used to adjust the screen contrast. I typically use a 10K Ohm potentiometer, but other values will also work.

 

Programming the Arduino

All of the code below uses the LiquidCrystal library that comes pre-installed with the Arduino IDE. A library is a set of functions that can be easily added to a program in an abbreviated format. In order to use a library, it needs be included in the program. Line 1 in the code below does this with the command #include <LiquidCrystal.h>. When you include a library in a program, all of the code in the library gets uploaded to the Arduino along with the code for your program.

Now we’re ready to get into the programming! I’ll go over more interesting things you can do in a moment, but for now let’s just run a simple test program. This program will print “hello, world!” to the screen. Enter this code into the Arduino IDE and upload it to the board:

 

#include <LiquidCrystal.h>

 

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

 

void setup() {

lcd.begin(16, 2);

lcd.print(“hello, world!”);

}

 

void loop() {

}

 

You have your display as below, cheers! 

 

LCD Display Options:

There are 19 different functions in the LiquidCrystal library available for us to use. These functions do things like change the position of the text, move text across the screen, or make the display turn on or off. What follows is a short description of each function, and how to use it in a program.

 

LiquidCrystal()

The LiquidCrystal() function sets the pins the Arduino uses to connect to the LCD. You can use any of the Arduino’s digital pins to control the LCD. Just put the Arduino pin numbers inside the parentheses in this order:

LiquidCrystal(RS, E, D4, D5, D6, D7)

RS, E, D4, D5, D6, D7 are the LCD pins.

For example, say you want LCD pin D7 to connect to Arduino pin 12. Just put “12” in place of D7 in the function like this: 

LiquidCrystal(RS, E, D4, D5, D6, 12)

This function needs to be placed before the void setup() section of the program.

 

lcd.begin()

This function sets the dimensions of the LCD. It needs to be placed before any other LiquidCrystal function in the void setup() section of the program. The number of rows and number of columns are specified as lcd.begin(columns, rows). For a 16×2 LCD, you would use lcd.begin(16, 2), and for a 20×4 LCD you would use lcd.begin(20, 4).

 

lcd.clear() 

This function clears any text or data already displayed on the LCD. If you use lcd.clear() with lcd.print() and the delay() function in the void loop() section, you can make a simple blinking text program. 

 

lcd.setCursor()

Similar, but more useful than lcd.home() is lcd.setCursor(). This function places the cursor (and any printed text) at any position on the screen. It can be used in the void setup() or void loop() section of your program.

The cursor position is defined with lcd.setCursor(column, row). The column and row coordinates start from zero (0-15 and 0-1 respectively). For example, using lcd.setCursor(2, 1) in the void setup() section of the “hello, world!” program above prints “hello, world!” to the lower line and shifts it to the right two spaces:

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

Liquidcrystal lcd (12, 11, 5, 4, 3, 2);

void setup () {

lcd.begin (16, 2);

lcd.setCursor (2, 1);

lcd.print(“hello, world!”);

}

void loop () {

}

 

lcd.blink()

This function creates a block style cursor that blinks on and off at approximately 500 milliseconds per cycle. Use it in the void loop() section. The function lcd.noBlink() disables the blinking block cursor. 

 

lcd.display()

This function turns on any text or cursors that have been printed to the LCD screen. The function lcd.noDisplay() turns off any text or cursors printed to the LCD, without clearing it from the LCD’s memory.

These two functions can be used together in the void loop() section to create a blinking text effect. This code will make the “hello, world!” text blink on and off.

 

lcd.scrollDisplayLeft()

This function takes anything printed to the LCD and moves it to the left. It should be used in the void loop() section with a delay command following it. The function will move the text 40 spaces to the left before it loops back to the first character. This code moves the “hello, world!” text to the left, at a rate of one second per character. 

 

lcd.scrollDisplayRight()

This function behaves like lcd.scrollDisplayLeft(), but moves the text to the right.

 

lcd.autoscroll()

This function takes a string of text and scrolls it from right to left in increments of the character count of the string. For example, if you have a string of text that is 3 characters long, it will shift the text 3 spaces to the left with each step. 

 

lcd.noAutoscroll()

lcd.noAutoscroll() turns the lcd.autoscroll() function off. Use this function before or after lcd.autoscroll() in the void loop() section to create sequences of scrolling text or animations.

 

lcd.rightToLeft()

This function sets the direction that text is printed to the screen. The default mode is from left to right using the command lcd.leftToRight(), but you may find some cases where it’s useful to output text in the reverse direction.

 

lcd.createChar()

This command allows you to create your own custom characters. Each character of a 16×2 LCD has a 5 pixel width and an 8 pixel height. Up to 8 different custom characters can be defined in a single program. To design your own characters, you’ll need to make a binary matrix of your custom character from an LCD character generator or map it yourself. This code creates a degree symbol (°).

 

The detailed LCD tutorial can be found in the article. ARDUINO LCD SET UP AND PROGRAMMING GUIDE or to check https://github.com/arduino-libraries/LiquidCrystal

 

What’s the difference between LCD Display Arduino and LCD Display Raspberry Pi?

Make it simple: Arduino has no OS (operation system), while Raspberry Pi has OS based on Linux. Have a look for Respberry Pi as below.