4 line lcd display arduino quotation

This website is using a security service to protect itself from online attacks. The action you just performed triggered the security solution. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data.

This tutorial includes everything you need to know about controlling a character LCD with Arduino. I have included a wiring diagram and many example codes. These displays are great for displaying sensor data or text and they are also fairly cheap.

The first part of this article covers the basics of displaying text and numbers. In the second half, I will go into more detail on how to display custom characters and how you can use the other functions of the LiquidCrystal Arduino library.

As you will see, you need quite a lot of connections to control these displays. I therefore like to use them with an I2C interface module mounted on the back. With this I2C module, you only need two connections to control the LCD. Check out the tutorial below if you want to use an I2C module as well:

These LCDs are available in many different sizes (16×2 1602, 20×4 2004, 16×1 etc.), but they all use the same HD44780 parallel interface LCD controller chip from Hitachi. This means you can easily swap them. You will only need to change the size specifications in your Arduino code.

For more information, you can check out the datasheets below. The 16×2 and 20×4 datasheets include the dimensions of the LCD and in the HD44780 datasheet you can find more information about the Hitachi LCD driver.

Most LCDs have a built-in series resistor for the LED backlight. You should find it on the back of the LCD connected to pin 15 (Anode). If your display doesn’t include a resistor, you will need to add one between 5 V and pin 15. It should be safe to use a 220Ω resistor, but this value might make your display a bit dim. You can check the datasheet for the maximum current rating of the backlight and use this to select an appropriate resistor value.

After you have wired up the LCD, you will need to adjust the contrast of the display. This is done by turning the 10 kΩ potentiometer clockwise or counterclockwise.

Plug in the USB connector of the Arduino to power the LCD. You should see the backlight light up. Now rotate the potentiometer until one (16×2 LCD) or 2 rows (20×4 LCD) of rectangles appear.

In order to control the LCD and display characters, you will need to add a few extra connections. Check the wiring diagram below and the pinout table from the introduction of this article.

We will be using the LCD in 4-bit mode, this means you don’t need to connect anything to D0-D3. The R/W pin is connected to ground, this will pull the pin LOW and set the LCD to WRITE mode.

To control the LCD we will be using the LiquidCrystal library. This library should come pre-installed with the Arduino IDE. You can find it by going to Sketch > Include Library > LiquidCrystal.

The example code below shows you how to display a message on the LCD. Next, I will show you how the code works and how you can use the other functions of the LiquidCrystal library.

After including the library, the next step is to create a new instance of the LiquidCrystal class. The is done with the function LiquidCrystal(rs, enable, d4, d5, d6, d7). As parameters we use the Arduino pins to which we connected the display. Note that we have called the display ‘lcd’. You can give it a different name if you want like ‘menu_display’. You will need to change ‘lcd’ to the new name in the rest of the sketch.

In the loop() the cursor is set to the third column and first row of the LCD with lcd.setCursor(2,0). Note that counting starts at 0, and the first argument specifies the column. If you do not specify the cursor position, the text will be printed at the default home position (0,0) if the display is empty, or behind the last printed character.

Next, the string ‘Hello World!’ is printed with lcd.print("Hello World!"). Note that you need to place quotation marks (” “) around the text. When you want to print numbers or variables, no quotation marks are necessary.

The LiquidCrystal Arduino library has many other built-in functions which you might find useful. You can find an overview of them below with explanation and some code snippets.

Clears the LCD screen and positions the cursor in the upper-left corner (first row and first column) of the display. You can use this function to display different words in a loop.

This function turns off any text or cursors printed to the LCD. The text/data is not cleared from the LCD memory. This means it will be shown again when the function display() is called.

Scrolls the contents of the display (text and cursor) one space to the left. You can use this function in the loop section of the code in combination with delay(500), to create a scrolling text animation.

This function turns on automatic scrolling of the LCD. This causes each character output to the display to push previous characters over by one space. If the current text direction is left-to-right (the default), the display scrolls to the left; if the current direction is right-to-left, the display scrolls to the right. This has the effect of outputting each new character to the same location on the LCD.

The following example sketch enables automatic scrolling and prints the character 0 to 9 at the position (16,0) of the LCD. Change this to (20,0) for a 20×4 LCD.

With the function createChar() it is possible to create and display custom characters on the LCD. This is especially useful if you want to display a character that is not part of the standard ASCII character set.

Technical info: LCDs that are based on the Hitachi HD44780 LCD controller have two types of memories: CGROM and CGRAM (Character Generator ROM and RAM). CGROM generates all the 5 x 8 dot character patterns from the standard 8-bit character codes. CGRAM can generate user-defined character patterns.

/* Example sketch to create and display custom characters on character LCD with Arduino and LiquidCrystal library. For more info see www.www.makerguides.com */

After including the library and creating the LCD object, the custom character arrays are defined. Each array consists of 8 bytes, 1 byte for each row. In this example 8 custom characters are created.

In this article I have shown you how to use an alphanumeric LCD with Arduino. I hope you found it useful and informative. If you did, please share it with a friend that also likes electronics and making things!

I would love to know what projects you plan on building (or have already built) with these LCDs. If you have any questions, suggestions, or if you think that things are missing in this tutorial, please leave a comment down below.

This website is using a security service to protect itself from online attacks. The action you just performed triggered the security solution. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data.

In this tutorial, I’ll explain how to set up an LCD on an Arduino and show you all the different ways you can program it. I’ll show you how to print text, scroll text, make custom characters, blink text, and position text. They’re great for any project that outputs data, and they can make your project a lot more interesting and interactive.

The display I’m using is a 16×2 LCD display that I bought for about $5. You may be wondering why it’s called a 16×2 LCD. The part 16×2 means that the LCD has 2 lines, and can display 16 characters per line. Therefore, a 16×2 LCD screen can display up to 32 characters at once. It is possible to display more than 32 characters with scrolling though.

The code in this article is written for LCD’s that use the standard Hitachi HD44780 driver. If your LCD has 16 pins, then it probably has the Hitachi HD44780 driver. These displays can be wired in either 4 bit mode or 8 bit mode. Wiring the LCD in 4 bit mode is usually preferred since it uses four less wires than 8 bit mode. In practice, there isn’t a noticeable difference in performance between the two modes. In this tutorial, I’ll connect the LCD in 4 bit mode.

Here’s a diagram of the pins on the LCD I’m using. The connections from each pin to the Arduino will be the same, but your pins might be arranged differently on the LCD. Be sure to check the datasheet or look for labels on your particular LCD:

Also, you might need to solder a 16 pin header to your LCD before connecting it to a breadboard. Follow the diagram below to wire the LCD to your 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 . 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 lets 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:

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.

TheLiquidCrystal() 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:

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 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).

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:

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:

You can use this function to write different types of data to the LCD, for example the reading from a temperature sensor, or the coordinates from a GPS module. You can also use it to print custom characters that you create yourself (more on this below). Use lcd.write() in the void setup() or void loop() section of your program.

The function lcd.noCursor() turns the cursor off. lcd.cursor() and lcd.noCursor() can be used together in the void loop() section to make a blinking cursor similar to what you see in many text input fields:

Cursors can be placed anywhere on the screen with the lcd.setCursor() function. This code places a blinking cursor directly below the exclamation point in “hello, world!”:

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.

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.

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:

Like the lcd.scrollDisplay() functions, the text can be up to 40 characters in length before repeating. At first glance, this function seems less useful than the lcd.scrollDisplay() functions, but it can be very useful for creating animations with custom characters.

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.

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:

This code prints the “hello, world!” text as “!dlrow ,olleh”. Unless you specify the placement of the cursor with lcd.setCursor(), the text will print from the (0, 1) position and only the first character of the string will be visible.

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 (°):

On previous tutorials on our website, we have covered the use of several displays, LCDs, and TFTs, with diverse Arduino boards. From Nokia 5110 LCD display to different types of OLEDs, the reason for the tutorials has been to ensure that, as a reader, you know how to use many of the most popular displays so this help you make the best choice when trying to select the perfect display for your project. For today’s tutorial, we will continue in that line and examine how to use the 20×4 I2C Character LCD Display with Arduino.

The 20×4 LCD display is essentially a bigger (increased number of rows and columns) version of the 16×2 LCD display with which we have built several projects. The display has room to display 20 columns of characters on 4 rows which makes it perfect for displaying a large amount of text without scrolling. Each of the columns has a resolution of 5×8 pixels which ensures its visibility from a substantial distance. Asides its size, the interesting thing about this version of the display being used for today’s tutorial is the fact that it communicates via I2C, which means we will only require 2 wires asides GND and VCC to connect the display to the Arduino. This is possible via the Parallel to I2C module coupled to the display as shown in picture below. The I2C module can also be bought individually, and coupled to the 16 pins version of the display.

To demonstrate how to use this display, we will build a real-time clock which will display date and time on the LCD. To generate and keep track of date and time, we will use the DS3231 Real time clock. We covered the use of the DS3231 RTC module in the tutorial on DS3231 based Real-time Clock, you can check it out to learn more about its use with the Arduino.

The exact component used for this tutorial can be bought via the links attached and the power bank is only required to run the Arduino when not connected to the computer. You can replace this with a 9V battery and a center-positive power jack.

Since the display and the real-time clock are both I2C devices, they will be connected to the same pins on the Arduino. For the Arduino Uno, the I2C pins are located on Pin A5 (SCL) and A4 (SDA). This may differ on any of the other Arduino boards. Connect the components as shown in the schematics below;

To write the code for this project, we will use three main libraries; the DS1307 Library to easily interface with the DS3231 module, the liquid crystal I2C library to easily interface with the LCD display, and the Wire library for I2C communication. While the Wire library comes built into the Arduino IDE, the other two libraries can be downloaded and installed via the links attached to them.

As mentioned during the introduction, our task for today is to obtain time and date information from the RTC module and display on the LCD. As usual, I will do a breakdown of the code and try to explain some of the concepts within it that may be difficult to understand.

We start the code by including the libraries that will be used. After which we create an object of the Liquid crystal library, with the I2C address of the LCD as an argument. The I2C address can be obtained from the seller or as described in our tutorial on using the 16×2 LCD display to ESP32.

Next, we create a set of variables which comprises of byte arrays that represent custom characters to be created and displayed.  The custom characters are usually 5pixels in width and 8 pixels in height, representing each box in the rows or columns of the LCD. The byte array represents which pixels of the box to be turned on or off.

Next, we write the void setup function and start by initializing the library using the lcd.begin() function, with the first argument representing the number of columns, and the second argument representing the number of rows. After this, the CreateCustomCharacters() function is called to convert the char variables created above into characters that can be displayed on the LCD. One of the characters created is then used to create a UI/frame which is displayed using the printFrame() function.

The first function is the printTime() which breaks down the time data stored in the “tm” variable to extract seconds, minutes and hour values. These values are then displayed on the LCD using the lcd.print() function.

The printDate function is similar to the printTime function. It extracts date information from the variable tm and uses the lcd.print() function to display it.

The printFrame() function, on the other hand, was used to create a sort of user interface for the project. it makes use of the characters created above. Each of the custom characters created is displayed using the lcd.write(byte(x)) function with x being the character number of the character to be displayed. The characters are positioned on the LCD using the lcd.setCursor() function which takes numbers representing the column and row on which the character is to be displayed, as arguments.

As usual, go over the schematics to be sure everything is connected as it should be, then connect the Arduino board to your PC and upload the code to it. Ensure all the libraries have been installed to avoid errors.

Different projects, come with different screen requirements. If you need to display a large amount of information and the size is not a constraint, the 20×4 I2C display is definitely one of the options you should consider.

ERM2004SYG-3 is small size 20 characters wide,4 rows character lcd module,SPLC780C controller (Industry-standard HD44780 compatible controller),6800 4/8-bit parallel interface,single led backlight with yellow green color included can be dimmed easily with a resistor or PWM,stn-lcd positive,dark blue text on the yellow green color,wide operating temperature range,rohs compliant,built in character set supports English/Japanese text, see the SPLC780C datasheet for the full character set, It"s optional for pin header connection,5V or 3.3V power supply and I2C adapter board for arduino.

It"s easily controlled by MCU such as 8051,PIC,AVR,ARDUINO,ARM and Raspberry Pi.It can be used in any embedded systems,industrial device,security,medical and hand-held equipment.

Granted, the Arduino doesn’t have much use for text when used on it’s own. It has no display. But a display can be attached, or text can be send/received through the serial port and other ways of communication.

In the case of a string, the array keeps going, until your Arduino finds a NULL character. The NULL character terminates the string – or indicates the end of the string.

It’s character zero. But we do not (yet) have to worry about that – but it is something to keep in mind. Since strings are quite often used, the language “C” which we use for Arduino Programming, comes with a standard library of string related functions, which handle quite a lot already automatically.

Note that if the number is bigger than the number of characters we need, then this will work just fine. However, your Arduino might allocate the extra characters as well and waste memory space as we’re not using it. On the other hand, if you expect the string to change in the program and all those characters might be needed, then you’d already be prepared.

The code highlighting of the Arduino IDE text editor, will show you if a string “breaks” or not, by changing character colors in the string you just typed.

The first line shows us the wrong way of doing it. The keywords of importance are printed in orange en the string in a green-like color. But … our string has a chunk of black text in it. The word “guest” is black. It means that this is not part of the string, which is caused by the double quotes around the word “guest”.

The third line shows us the trick with the backslash. We placed them right before the special character, so the compiler knows that the next character is special and part of the string.

Note that when you want the next character to be special as well, then you’d need to “escape” those as well. For example if we add multiple double quotes around the word “guest”: Serial.println("Hello \"\"guest\"\", welcome to Arduino");

This trick has to be used for certain other characters as well, for example starting a new line is an ASCII character (see the character table, and look in the “Esc” column). If we’d like to place a line break (start a new line) in our string, then we would need ASCII character 10, which we write as “\n”.

What this does, is that the compiler will guess the required array space, one time only! This means that it will see the string “Hans” and will determine that these 4 characters will need an array of 5 characters (text plus NULL character).

When we added ” has two nephews, called Bram and Max!” to that string/array, we royally exceed the pre-defined space, and your Arduino will try to print that anyway. Not being able to find the NULL character (we have overwritten it with a non-NULL character, a space-character, in this example), it will keep spitting out whatever is in memory until it finds a NULL character. Which might be right away, or never …

With “Serial” we have already seen the methods (functions) “begin”, “print” and “println”. We call these methods to have the object do something , like start communication, or send a string to our Serial Monitor of our Arduino IDE.

As mentioned and shown before: the array of char variant of a string is a little cumbersome to work with. So the good people at Arduino created an object to make working with strings easier. Again a reminder: it’s the “String” with a capital “S”!!!

As we have seen with the old “string”, we can simply create a variable and assign it a value in one single line. Nothing new there, well except for the keyword “String” of course and the lack of square brackets.

Line 10 could also be written as Name = String("Bram"); , which will actually work as well, but now we assign the new object (holding the string “Bram”) to the old object, versus the method in the code where we assign just a string to the object.

We create the String object “Name” and assign it the value “Hans” (lines 7 and 8), which we can print with “Serial” as we have seen before. Now in line 12, we retrieve the length of our string – which is just the number of characters in the string, and not including the NULL terminating character. This is done with the “length()” method of the “String” object: Name.length() . This method will return a number, an integer, which we send right away to “Serial.print”.

In line 14, we call the method “concat()” to concatenate ” has two nephews, called Bram and Max!” to the original string “Hans”. As you can see, this works right away. But … there is an easier way to glue an extra string to your “String” object by simply using the plus symbol (+), even the compound operator “+=” works. See lines 27 and 28, where we use “+=” and even the regular “+”.

The “String” object however is even more powerful and can right away convert a number (int in this example) to a string, and replace or attach it to an existing string – see line 34 – which is something we cannot do with the previous “string” array of characters.

Now if we know that String("some text") returns a “String” object, and we know that we can glue strings together with the plus symbol (+), and we know that “Serial.println()” take a “String” as a parameter,… then we can do some tricks to save us the hassle of writing 2 “Serial” lines (print() and println()) whenever we want to print values or variables.

If you followed my first article for getting your Arduino Nano set up (Getting Started With Arduino Using the Small, Inexpensive Nano Board[^]), you are ready to do more with your Nano now.

Most of the code samples from the Arduino site add in lines that write information to the Serial port which can then be viewed in the Arduino IDE Serial Monitor program. However, that is a bit annoying because each time you go to send upload your code to your Arudino, you"ll need to make sure the Serial Monitor isn"t running or else, you"ll often get a conflict since the Arduino is writing statements to the Serial Monitor and the program is trying to upload the new program to the Arudino.

It is so easy to add a 20 (character) X 4 (character) LCD (Liquid Crystal Display) to your Nano that I thought it might make a helpful article to show you which one to get and how to quickly hook it up and use it.

So that we have some interesting data to display, I"ll show you how to read varying values from an input pin. We can cause the values to vary easily by attaching a potentiometer to an analog pin and I"ll show you how to do that.

When I started working with the Arduino, I waited far too long to order a simple output device (LCD) and learn how to use it. It is so simple and so helpful it should really be one of the first things you learn to do. Once you do, I believe you"ll find that it opens up your Arduino programming in a dramatic way as it empowers you to know more about what the code is actually doing. Plus, it"s fun to see your little device writing to the screen.

This one includes the I2C interface (Inter-Integrated Circuit which is a binary serial communication protocol). This protocol is also known as TWI - Two Wire Interface. The LCD is only about $9.50.

Two are to power the LCD (voltage and ground), one is to carry the serial data (which will be displayed) and the fourth one is the serial clock which manages the speed for the transmitted data.

Now, compare the previous LCD to a similar one that does not implement I2C (uses a parallel interface instead). You can see that there are far more wires to deal with. Those wires will take up more of your Arduino"s pins too so if you"re building a larger project, that could limit you.

I suffered quite a bit with that 20x4 LCD because my soldering skills were poor and if any one of the data lines is hooked up perfectly properly, you will not see anything or you will see garbled characters and odd output. It is quite difficult to determine which line isn"t connected properly.

I highlighted the pins where I saw the notation for SCL and SDA with the red box. This indicates that all we have to do is connect the SDA pin to A4 and the SCL pin to A5 and the LCD will work for us.

Although using the LCD with the I2C module is much easier because there is less wiring, the I2C module isn"t directly provided with the other base libraries. Instead, we need to download it and drop it in our Arduino IDE installation directory.

Whenever an include statement uses the < and > brackets, it means that the default library paths will be searched and that is why we added the new files to our \libraries directory under the Arduino IDE installation.

Next, we need to initialize the object we will use to call the LCD functionality. We will call the object lcd. Since this object will be used throughout the program, we will initialize it in the global space outside the setup() method and the loop()method.

If you don"t have a 5K pot, you can basically grab whatever you have available. That"s because the analogRead()method has a scale of 0-1023 and it will divide the value of the voltage applied into 1024 parts so that no matter what the value, it will return a value between 0-1023. However, if you have a really small pot value like 100, you will turn the knob just a little bit and the value will change drastically.

int a3Value = analogRead(analogPin); //1 lcd.setCursor(2,1); //2 sprintf(formattedValue, "%04d", a3Value); //3 lcd.print(formattedValue); //4}

Line 3: We call the C function sprintf()(string print format) to format the a3Value (last parameter) and copy it into the formattedValue character array.

What is the purpose of declaring LiquidCrystal_I2C lcd(0x27, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE); if we are using pins A4 and A5? I know that 0x27 is the ic address but what is the rest for?

I am getting a error while i m going to add zip file of lcd library error id this zip file does not contains a valid library please help me to resolve this issue as soon as possible.....

Hey guys. My LCD works fine using the above instructions (when replacing the existing LCD library in the Arduino directory) but I can"t get the backlight to ever switch off. Suggestions?

Most of the time we use the serial plotter of the Arduino IDE to visualize our solutions or output of a sketch. This is great and a big time saver when you are doing prototyping. But there is a time when your system will go live. If you are for example only sending data from sensors to a database on a Raspberry Pi, than you are able to view the output remote from your PC by connecting to the database. But there are use cases like an indoor weather station, where you want to see the output like the current temperature directly and not when you are on you PC.

Than displays are the way to go. There are different kinds of displays like 7 Segment LED display, 4 Digit 7 Segment display, 8×8 Dot Matrix display, OLED display or the easiest and cheapest version the liquid crystal display (LCD).

Most LCD displays have either 2 rows with 16 characters per row or 4 rows with 20 characters per row. There are LCD screen with and without I2C module. I highly suggest the modules with I2C because the connection to the board is very easy and there are only 2 instead of 6 pins used. But we will cover the LCD screen with and without I2C module in this article.

The LCD display has an operating voltage between 4.7V and 5.3V with a current consumption of 1mA without backlight and 120mA with full backlight. There are version with a green and also with a blue backlight color. Each character of the display is build by a 5×8 pixel box and is therefore able to display custom generated characters. Because each character is build by (5×8=40) 40 pixels a 16×2 LCD display will have 16x2x40= 1280 pixels in total. The LCD module is able to operate in 8-bit and 4-bit mode. The difference between the 4-bit and 8-bit mode are the following:

If we use the LCD display version without I2C connection we have to add the potentiometer manually to control the contrast of the screen. The following picture shows the pinout of the LCD screen.

Also I added a table how to connect the LCD display with the Arduino Uno and the NodeMCU with a description of the LCD pin. To make it as easy as possible for you to connect your microcontroller to the display, you find the corresponding fritzing connection picture for the Arduino Uno and the NodeMCU in this chapter.

3VEEPotentiometerPotentiometerAdjusts the contrast of the display If this pin is grounded, you get the maximum contrast. We will connect the VEE pin to the potentiometer output to adjust the contrast by changing the resistance of the potentiometer.

4RSD12D2Select command register to low when we are sending commands to the LCD like set the cursor to a specific location, clear the display or turn off the display.

8Data Pin 1 (d1)Data pins 0 to 7 forms an 8-bit data line. The Data Pins are connection to the Digital I/O pins of the microcontroller to send 8-bit data. These LCD’s can also operate on 4-bit mode in such case Data pin 4,5,6 and 7 will be left free.

Of cause we want to try the connection between the microcontroller and the LCD display. Therefore you find an example sketch in the Arduino IDE. The following section shows the code for the sketch and a picture of the running example, more or less because it is hard to make a picture of the screen ;-). The example prints “hello, world!” in the first line of the display and counts every second in the second row. We use the connection we described before for this example.

Looks very complicated to print data onto the LCD screen. But don’t worry like in most cases if it starts to get complicated, there is a library to make the word for us. This is also the case for the LCD display without I2C connection.

Therefore the next step is to install the library “LiquidCrystal”. You find here an article how to install an external library via the Arduino IDE. After you installed the library successful you can include the library via: #include < LiquidCrystal.h>.

Like I told you, I would suggest the LCD modules with I2C because you only need 2 instead of 6 pins for the connection between display and microcontroller board. In the case you use the I2C communication between LCD and microcontroller, you need to know the I2C HEX address of the LCD. In this article I give you a step by step instruction how to find out the I2C HEX address of a device. There is also an article about the I2C communication protocol in detail.

The following picture shows how to connect an I2C LCD display with an Arduino Uno. We will use exact this connection for all of the examples in this article.

To use the I2C LCD display we have to install the required library “LiquidCrystal_I2C” by Frank de Brabander. You find here an article how to install an external library via the Arduino IDE. After you installed the library successful you can include the library via: #include < LiquidCrystal_I2C.h>.

The LiquidCrystal library has 20 build in functions which are very handy when you want to work with the LCD display. In the following part of this article we go over all functions with a description as well as an example sketch and a short video that you can see what the function is doing.

LiquidCrystal_I2C()This function creates a variable of the type LiquidCrystal. The parameters of the function define the connection between the LCD display and the Arduino. You can use any of the Arduino digital pins to control the display. The order of the parameters is the following: LiquidCrystal(RS, R/W, Enable, d0, d1, d2, d3, d4, d5, d6, d7)

If you are using an LCD display with the I2C connection you do not define the connected pins because you do not connected to single pins but you define the HEX address and the display size: LiquidCrystal_I2C lcd(0x27, 20, 4);

xlcd.begin()The lcd.begin(cols, rows) function has to be called to define the kind of LCD display with the number of columns and rows. The function has to be called in the void setup() part of your sketch. For the 16x2 display you write lcd.begin(16,2) and for the 20x4 lcd.begin(20,4).

xxlcd.clear()The clear function clears any data on the LCD screen and positions the cursor in the upper-left corner. You can place this function in the setup function of your sketch to make sure that nothing is displayed on the display when you start your program.

xxlcd.setCursor()If you want to write text to your LCD display, you have to define the starting position of the character you want to print onto the LCD with function lcd.setCursor(col, row). Although you have to define the row the character should be displayed.

xxlcd.print()This function displays different data types: char, byte, int, long, or string. A string has to be in between quotation marks („“). Numbers can be printed without the quotation marks. Numbers can also be printed in different number systems lcd.print(data, BASE) with BIN for binary (base 2), DEC for decimal (base 10), OCT for octal (base 8), HEX for hexadecimal (base 16).

xlcd.println()This function displays also different data types: char, byte, int, long, or string like the function lcd.print() but lcd.println() prints always a newline to output stream.

xxlcd.display() / lcd.noDisplay()This function turn on and off any text or cursor on the display but does not delete the information from the memory. Therefore it is possible to turn the display on and off with this function.

xxlcd.scrollDisplayLeft() / lcd.scrollDisplayRight()This function scrolls the contents of the display (text and cursor) a one position to the left or to the right. After 40 spaces the function will loops back to the first character. With this function in the loop part of your sketch you can build a scrolling text function.

Scrolling text if you want to print more than 16 or 20 characters in one line, than the scrolling text function is very handy. First the substring with the maximum of characters per line is printed, moving the start column from the right to the left on the LCD screen. Than the first character is dropped and the next character is printed to the substring. This process repeats until the full string is displayed onto the screen.

xxlcd.autoscroll() / lcd.noAutoscroll()The autoscroll function turn on or off the functionality that each character is shifted by one position. The function can be used like the scrollDisplayLeft / scrollDisplayRight function.

xxlcd. leftToRight() / lcd.rightToLeft()The leftToRight and rightToLeft functions changes the direction for text written to the LCD. The default mode is from left to right which you do not have to define at the start of the sketch.

xxlcd.createChar()There is the possibility to create custom characters with the createChar function. How to create the custom characters is described in the following chapter of this article as well as an example.

xlcd.backlight()The backlight function is useful if you do not want to turn off the whole display (see lcd.display()) and therefore only switch on and off the backlight. But before you can use this function you have to define the backlight pin with the function setBacklightPin(pin, polarity).

xlcd.moveCursorLeft() / lcd.moveCursorRight()This function let you move the curser to the left and to the right. To use this function useful you have to combine it with lcd.setCursor() because otherwise there is not cursor to move left or right. For our example we also use the function lcd.cursor() to make the cursor visible.

xlcd.on() / lcd.off()This function switches the LCD display on and off. It will switch on/off the LCD controller and the backlight. This method has the same effect of calling display/noDisplay and backlight/noBacklight.

Show or hide a cursor (“_”) that is useful when you create a menu as navigation bar from the left to the right or from the top to the bottom, depending on a horizontal of vertical menu bar. If you are interested how to create a basic menu with the ESP or Arduino microcontroller in combination with the display, you find here a tutorial.

The following code shows you the Arduino program to use all three LCD display functions of the library divided into three separate functions. Also the video after the program shows the functions in action.

The creation of custom characters is very easy if you use the previous mentioned libraries. The LiquidCrystal and also the LiquidCrystal_I2C library have the function “lcd.createChar()” to create a custom character out of the 5×8 pixels of one character. To design your own characters, you need to make a binary matrix of your custom character from an LCD character generator or map it yourself. This code creates a wiggling man.

In the section of the LCD display pinout without I2C we saw that if we set the RS pin to how, that we are able to send commands to the LCD. These commands are send by the data pins and represented by the following table as HEX code.

During this second week with Ian we learned how to use libraries and displays on Arduino. First of all Ian gived us two documents to install, one was the library and the other one was the code.

I don’t know why on my computer the code wasn’t working, so i just tried to install another LiquidCrystal_I2C.h library and i changed the code by myself, then i added the library to the Arduino environment.

Arduino LCD Display Modules are mostly used in embedded projects, because of its affordability and availability. The 16×2 Display LCD Module represents 16 Columns and 2 Rows. There are so many other combinations like 8×1, 8×2, 10×2, 16×1 and so on. However, 16 x 2 display LCD is most commonly used.

Arduino 16×2 LCD Display Module has 16 characters by a 2-line LCD display screen with an I2C interface. It displays 2 lines of 16 characters, white characters are displayed on a blue background.

This I2C 16×2 Arduino LCD Display Module uses the I2C communication interface. This means that we can use 4 pins for the display that is: VCC, GND, SDA, SCL. Thus, it gives us the advantage of saving 4 digital / analog pins on Arduino.

This website is using a security service to protect itself from online attacks. The action you just performed triggered the security solution. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data.