arduino lcd module tutorial supplier

Do you want your Arduino projects to display status messages or sensor readings? Then these LCD displays can be a perfect fit. They are extremely common and fast way to add a readable interface to your project.

This tutorial will help you get up and running with not only 16×2 Character LCD, but any Character LCD (16×4, 16×1, 20×4 etc.) that is based on Hitachi’s LCD Controller Chip – HD44780.

True to their name, these LCDs are ideal for displaying only text/characters. A 16×2 character LCD, for example, has an LED backlight and can display 32 ASCII characters in two rows of 16 characters each.

The good news is that all of these displays are ‘swappable’, which means if you build your project with one you can just unplug it and use another size/color LCD of your choice. Your code will have to change a bit but at least the wiring remains the same!

Vo (LCD Contrast) controls the contrast and brightness of the LCD. Using a simple voltage divider with a potentiometer, we can make fine adjustments to the contrast.

RS (Register Select) pin is set to LOW when sending commands to the LCD (such as setting the cursor to a specific location, clearing the display, etc.) and HIGH when sending data to the LCD. Basically this pin is used to separate the command from the data.

R/W (Read/Write) pin allows you to read data from the LCD or write data to the LCD. Since we are only using this LCD as an output device, we are going to set this pin LOW. This forces it into WRITE mode.

E (Enable) pin is used to enable the display. When this pin is set to LOW, the LCD does not care what is happening on the R/W, RS, and data bus lines. When this pin is set to HIGH, the LCD processes the incoming data.

Now we will power the LCD. The LCD has two separate power connections; One for the LCD (pin 1 and pin 2) and the other for the LCD backlight (pin 15 and pin 16). Connect pins 1 and 16 of the LCD to GND and 2 and 15 to 5V.

Most LCDs have a built-in series resistor for the LED backlight. You’ll find this near pin 15 on the back of the LCD. If your LCD does not include such a resistor or you are not sure if your LCD has one, you will need to add one between 5V and pin 15. It is safe to use a 220 ohm resistor, although a value this high may make the backlight a bit dim. For better results you can check the datasheet for maximum backlight current and select a suitable resistor value.

Next we will make the connection for pin 3 on the LCD which controls the contrast and brightness of the display. To adjust the contrast we will connect a 10K potentiometer between 5V and GND and connect the potentiometer’s center pin (wiper) to pin 3 on the LCD.

That’s it. Now turn on the Arduino. You will see the backlight lit up. Now as you turn the knob on the potentiometer, you will start to see the first row of rectangles. If that happens, Congratulations! Your LCD is working fine.

Let’s finish connecting the LCD to the Arduino. We have already made the connections to power the LCD, now all we have to do is make the necessary connections for communication.

We know that there are 8 data pins that carry data to the display. However, HD44780 based LCDs are designed in such a way that we can communicate with the LCD using only 4 data pins (4-bit mode) instead of 8 (8-bit mode). This saves us 4 pins!

The sketch begins by including the LiquidCrystal library. The Arduino community has a library called LiquidCrystal which makes programming of LCD modules less difficult. You can find more information about the library on Arduino’s official website.

First we create a LiquidCrystal object. This object uses 6 parameters and specifies which Arduino pins are connected to the LCD’s RS, EN, and four data pins.

In the ‘setup’ we call two functions. The first function is begin(). It is used to specify the dimensions (number of columns and rows) of the display. If you are using a 16×2 character LCD, pass the 16 and 2; If you’re using a 20×4 LCD, pass 20 and 4. You got the point!

After that we set the cursor position to the second row by calling the function setCursor(). The cursor position specifies the location where you want the new text to be displayed on the LCD. The upper left corner is assumed to be col=0, row=0.

There are some useful functions you can use with LiquidCrystal objects. Some of them are listed below:lcd.home() function is used to position the cursor in the upper-left of the LCD without clearing the display.

lcd.scrollDisplayRight() function scrolls the contents of the display one space to the right. If you want the text to scroll continuously, you have to use this function inside a for loop.

lcd.scrollDisplayLeft() function scrolls the contents of the display one space to the left. Similar to above function, use this inside a for loop for continuous scrolling.

If you find the characters on the display dull and boring, you can create your own custom characters (glyphs) and symbols for your LCD. They are extremely useful when you want to display a character that is not part of the standard ASCII character set.

As discussed earlier in this tutorial a character is made up of a 5×8 pixel matrix, so you need to define your custom character within that matrix. You can use the createChar() function to define a character.

CGROM is used to store all permanent fonts that are displayed using their ASCII codes. For example, if we send 0x41 to the LCD, the letter ‘A’ will be printed on the display.

CGRAM is another memory used to store user defined characters. This RAM is limited to 64 bytes. For a 5×8 pixel based LCD, only 8 user-defined characters can be stored in CGRAM. And for 5×10 pixel based LCD only 4 user-defined characters can be stored.

Creating custom characters has never been easier! We have created a small application called Custom Character Generator. Can you see the blue grid below? You can click on any 5×8 pixel to set/clear that particular pixel. And as you click, the code for the character is generated next to the grid. This code can be used directly in your Arduino sketch.

If you’ve ever tried to connect an LCD display to an Arduino, you might have noticed that it consumes a lot of pins on the Arduino. Even in 4-bit mode, the Arduino still requires a total of seven connections – which is half of the Arduino’s available digital I/O pins.

The solution is to use an I2C LCD display. It consumes only two I/O pins that are not even part of the set of digital I/O pins and can be shared with other I2C devices as well.

True to their name, these LCDs are ideal for displaying only text/characters. A 16×2 character LCD, for example, has an LED backlight and can display 32 ASCII characters in two rows of 16 characters each.

At the heart of the adapter is an 8-bit I/O expander chip – PCF8574. This chip converts the I2C data from an Arduino into the parallel data required for an LCD display.

If you are using multiple devices on the same I2C bus, you may need to set a different I2C address for the LCD adapter so that it does not conflict with another I2C device.

An important point here is that several companies manufacture the same PCF8574 chip, Texas Instruments and NXP Semiconductors, to name a few. And the I2C address of your LCD depends on the chip manufacturer.

So your LCD probably has a default I2C address 0x27Hex or 0x3FHex. However it is recommended that you find out the actual I2C address of the LCD before using it.

Connecting an I2C LCD is much easier than connecting a standard LCD. You only need to connect 4 pins instead of 12. Start by connecting the VCC pin to the 5V output on the Arduino and GND to ground.

Now we are left with the pins which are used for I2C communication. Note that each Arduino board has different I2C pins that must be connected accordingly. On Arduino boards with the R3 layout, the SDA (data line) and SCL (clock line) are on the pin headers close to the AREF pin. They are also known as A5 (SCL) and A4 (SDA).

After wiring up the LCD you’ll need to adjust the contrast of the display. On the I2C module you will find a potentiometer that you can rotate with a small screwdriver.

Plug in the Arduino’s USB connector to power the LCD. You will see the backlight lit up. Now as you turn the knob on the potentiometer, you will start to see the first row of rectangles. If that happens, Congratulations! Your LCD is working fine.

To drive an I2C LCD you must first install a library called LiquidCrystal_I2C. This library is an enhanced version of the LiquidCrystal library that comes with your Arduino IDE.

The I2C address of your LCD depends on the manufacturer, as mentioned earlier. If your LCD has a Texas Instruments’ PCF8574 chip, its default I2C address is 0x27Hex. If your LCD has NXP Semiconductors’ PCF8574 chip, its default I2C address is 0x3FHex.

So your LCD probably has I2C address 0x27Hex or 0x3FHex. However it is recommended that you find out the actual I2C address of the LCD before using it. Luckily there’s an easy way to do this, thanks to the Nick Gammon.

But, before you proceed to upload the sketch, you need to make a small change to make it work for you. You must pass the I2C address of your LCD and the dimensions of the display to the constructor of the LiquidCrystal_I2C class. If you are using a 16×2 character LCD, pass the 16 and 2; If you’re using a 20×4 LCD, pass 20 and 4. You got the point!

In ‘setup’ we call three functions. The first function is init(). It initializes the LCD object. The second function is clear(). This clears the LCD screen and moves the cursor to the top left corner. And third, the backlight() function turns on the LCD backlight.

After that we set the cursor position to the third column of the first row by calling the function lcd.setCursor(2, 0). The cursor position specifies the location where you want the new text to be displayed on the LCD. The upper left corner is assumed to be col=0, row=0.

There are some useful functions you can use with LiquidCrystal_I2C objects. Some of them are listed below:lcd.home() function is used to position the cursor in the upper-left of the LCD without clearing the display.

lcd.scrollDisplayRight() function scrolls the contents of the display one space to the right. If you want the text to scroll continuously, you have to use this function inside a for loop.

lcd.scrollDisplayLeft() function scrolls the contents of the display one space to the left. Similar to above function, use this inside a for loop for continuous scrolling.

If you find the characters on the display dull and boring, you can create your own custom characters (glyphs) and symbols for your LCD. They are extremely useful when you want to display a character that is not part of the standard ASCII character set.

As discussed earlier in this tutorial a character is made up of a 5×8 pixel matrix, so you need to define your custom character within that matrix. You can use the createChar() function to define a character.

CGROM is used to store all permanent fonts that are displayed using their ASCII codes. For example, if we send 0x41 to the LCD, the letter ‘A’ will be printed on the display.

CGRAM is another memory used to store user defined characters. This RAM is limited to 64 bytes. For a 5×8 pixel based LCD, only 8 user-defined characters can be stored in CGRAM. And for 5×10 pixel based LCD only 4 user-defined characters can be stored.

Creating custom characters has never been easier! We have created a small application called Custom Character Generator. Can you see the blue grid below? You can click on any 5×8 pixel to set/clear that particular pixel. And as you click, the code for the character is generated next to the grid. This code can be used directly in your Arduino sketch.

After the library is included and the LCD object is created, custom character arrays are defined. The array consists of 8 bytes, each byte representing a row of a 5×8 LED matrix. In this sketch, eight custom characters have been created.

The lcd.begin(16,2) command set up the LCD number of columns and rows. For example, if you have an LCD with 20 columns and 4 rows (20x4) you will have to change this to lcd.begin(20x4).

The lcd.print("--message--") command print a message to first column and row of lcd display. The "message" must have maximum length equal to lcd columns number. For example, for 16 columns display max length is equal with 16 and for 20 columns display max length is equal with 20.

Thelcd.setCursor(0,1) command will set cursor to first column of second row. If you have an LCD 20x4 and you want to print a message to column five and third row you have to use: lcd.setCursor(4,2).

Try downloading the codebender plugin and clicking on the Run on Arduino button to program your Arduino with this sketch. And that"s it, you"ve programmed your Arduino board!

The LCD can be connected in the 4 bit as well as 8 bit mode. In the 4 bit mode we have to use only the 4 data pins while in the 8 bit mode we will have to use all the 8 data pins. You can do almost everything in the 4 bit mode, so in this example we are going to connect it in the 4 bit mode.

The Arduino family of devices is features rich and offers many capabilities. The ability to interface to external devices readily is very enticing, although the Arduino has a limited number of input/output options. Adding an external display would typically require several of the limited I/O pins. Using an I2C interface, only two connections for an LCD character display are possible with stunning professional results. We offer both a 4 x 20 LCD.

The character LCD is ideal for displaying text and numbers and special characters. LCDs incorporate a small add-on circuit (backpack) mounted on the back of the LCD module. The module features a controller chip handling I2C communications and an adjustable potentiometer for changing the intensity of the LED backlight. An I2C LCD advantage is that wiring is straightforward, requiring only two data pins to control the LCD.

A standard LCD requires over ten connections, which can be a problem if your Arduino does not have many GPIO pins available. If you happen to have an LCD without an I2C interface incorporated into the design, these can be easily

The LCD displays each character through a matrix grid of 5×8 pixels. These pixels can display standard text, numbers, or special characters and can also be programmed to display custom characters easily.

Connecting the Arduino UNO to the I2C interface of the LCD requires only four connections. The connections include two for power and two for data. The chart below shows the connections needed.

The I2C LCD interface is compatible across much of the Arduino family. The pin functions remain the same, but the labeling of those pins might be different.

Located on the back of the LCD screen is the I2C interface board, and on the interface is an adjustable potentiometer. This adjustment is made with a small screwdriver. You will adjust the potentiometer until a series of rectangles appear – this will allow you to see your programming results.

The Arduino module and editor do not know how to communicate with the I2C interface on the LCD. The parameter to enable the Arduino to send commands to the LCD are in separately downloaded LiquidCrystal_I2C library.

Before installing LiquidCrystal_I2C, remove any other libraries that may reside in the Arduino IDE with the same LiquidCrystal_I2C name. Doing this will ensure that only the known good library is in use. LiquidCrystal_I2C works in combination with the preinstalled Wire.h library in the Arduino editor.

To install the LiquidCrystal_I2C library, use the SketchSketch > Include Library > Add .ZIP Library…from the Arduino IDE (see example). Point to the LiquidCrystal_I2C-master.zip which you previously downloaded and the Library will be installed and set up for use.

Several examples and code are included in the Library installation, which can provide some reference and programming examples. You can use these example sketches as a basis for developing your own code for the LCD display module.

There may be situations where you should uninstall the Arduino IDE. The reason for this could be due to Library conflicts or other configuration issues. There are a few simple steps to uninstalling the IDE.

The I2c address can be changed by shorting the address solder pads on the I2C module. You will need to know the actual address of the LCD before you can start using it.

Once you have the LCD connected and have determined the I2C address, you can proceed to write code to display on the screen. The code segment below is a complete sketch ready for downloading to your Arduino.

The code assumes the I2C address of the LCD screen is at 0x27 and can be adjusted on the LiquidCrystal_I2C lcd = LiquidCrystal_I2C(0x27,16,2); as required.

This function turns off any characters displayed to the LCD. The text will not be cleared from the LCD memory; rather, it is turned off. The LCD will show the screen again when display() is executed.

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

The LCD driver backpack has an exciting additional feature allowing you to create custom characters (glyph) for use on the screen. Your custom characters work with both the 16×2 and 20×4 LCD units.

To aid in creating your custom characters, there are a number of useful tools available on Internet. Here is a LCD Custom Character Generator which we have used.

The purpose of this guide is to get your 0.96″ color LCD display successfully operating with your Arduino, so you can move forward and experiment and explore further types of operation with the display. This includes installing the Arduino library, making a succesful board connection and running a demonstration sketch.

Although you can use the display with an Arduino Uno or other boad with an ATmega328-series microcontroller – this isn’t recommended for especially large projects. The library eats up a fair amount of flash memory – around 60% in most cases.

So if you’re running larger projects we recommend using an Arduino Mega or Due-compatible board due to the increased amount of flash memory in their host microcontrollers.

(As the display uses the ST7735S controller IC, you may be tempted to use the default TFT library included with the Arduino IDE – however it isn’t that reliable. Instead, please follow the instructions below).

The display uses the SPI data bus for communication, and is a 3.3V board. You can use it with an Arduino or other 5V board as the logic is tolerant of higher voltages.

This article includes everything you need to know about using acharacter I2C LCD with Arduino. I have included a wiring diagram and many example codes to help you get started.

Once you know how to display text and numbers on the LCD, I suggest you take a look at the articles below. In these tutorials, you will learn how to measure and display sensor data on the LCD.

Each rectangle is made up of a grid of 5×8 pixels. Later in this tutorial, I will show you how you can control the individual pixels to display custom characters on the LCD.

They all use the same HD44780 Hitachi LCD controller, so you can easily swap them. You will only need to change the size specifications in your Arduino code.

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

Note that an Arduino Uno with the R3 layout (1.0 pinout) also has the SDA (data line) and SCL (clock line) pin headers close to the AREF pin. Check the table below for more details.

After you have wired up the LCD, you will need to adjust the contrast of the display. On the I2C module, you will find a potentiometer that you can turn with a small screwdriver.

The LiquidCrystal_I2C library works in combination with the Wire.h library which allows you to communicate with I2C devices. This library comes pre-installed with the Arduino IDE.

To install this library, go to Tools > Manage Libraries (Ctrl + Shift + I on Windows) in the Arduino IDE. The Library Manager will open and update the list of installed libraries.

Note that counting starts at 0 and the first argument specifies the column. So lcd.setCursor(2,1) sets the cursor on the third column and the second row.

Next the string ‘Hello World!’ is printed with lcd.print("Hello World!"). Note that you need to place quotation marks (” “) around the text since we are printing a text string.

The example sketch above shows you the basics of displaying text on the LCD. Now we will take a look at the other functions of the LiquidCrystal_I2C library.

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.

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.

Hello friend welcome to “Techno-E-Solution” in this article we are going to learn how to connect LCD display with Arduino Uno and print "Hello World!" on LCD using Arduino Uno. The 16x2 LCD is most popular LCD in electronics projects. In upcoming project we need this display in our project so it"s the beginners level tutorial learn this tutorial with fun. So friends let"s get started..........

Previous examples connect the white LED backlight to power. The following example is specifically for those using an LCD with a RGB LED backlight. The only difference between the connection is the LED"s backlight on pins 15-18.

Copy and paste the code below. Just make sure to select the correct board (in this case the Arduino/ Genuino Uno) and the COM port that the Arduino enumerated on. Then upload the code to your Arduino.

After uploading, you will notice the same "Hello, world!" and time since the Arduino was last reset in the first example. The only difference is that the current color of the backlight will be printed as it cycles through each of the primary, secondary, and tertiary colors. You should see something similar to the image below.

LCD, or Liquid Crystal Displays, are great choices for many applications. They aren’t that power-hungry, they are available in monochrome or full-color models, and they are available in all shapes and sizes.

Today we will see how to use this display with both an Arduino and an ESP32. We will also use a pair of them to make some rather spooky animated eyeballs!

Waveshare actually has several round LCD modules, I chose the 1.28-inch model as it was readily available on Amazon. You could probably perform the same experiments using a different module, although you may require a different driver.

This display can be used for the experiments we will be doing with the ESP32, as that is a 3.3-volt logic microcontroller. You would need to use a voltage level converter if you wanted to use one of these with an Arduino Uno.

The Arduino Uno is arguably the most common microcontroller on the planet, certainly for experiments it is. However, it is also quite old and compared to more modern devices its 16-MHz clock is pretty slow.

The Waveshare device comes with a cable for use with the display. Unfortunately, it only has female ends, which would be excellent for a Raspberry Pi (which is also supported) but not too handy for an Arduino Uno. I used short breadboard jumper wires to convert the ends into male ones suitable for the Arduino.

The Waveshare Wiki does provide some information about the display and a bit of sample code for a few common controllers. It’s a reasonable support page, unfortunately, it is the only support that Waveshare provides(I would have liked to see more examples and a tutorial, but I guess I’m spoiled by Adafruit and Sparkfun LOL).

Open the Arduino folder. Inside you’ll find quite a few folders, one for each display size that Waveshare supports. As I’m using the 1.28-inch model, I selected theLCD_1inch28folder.

Once you do that, you can open your Arduino IDE and then navigate to that folder. Inside the folder, there is a sketch file namedLCD_1inch28.inowhich you will want to open.

When you open the sketch, you’ll be greeted by an error message in your Arduino IDE. The error is that two of the files included in the sketch contain unrecognized characters. The IDE offers the suggestion of fixing these with the “Fix Encoder & Reload” function (in the Tools menu), but that won’t work.

Unfortunately, Waveshare doesn’t offer documentation for this, but you can gather quite a bit of information by reading theLCD_Driver.cppfile, where the functions are somewhat documented.

Here is the hookup for the ESP32 and the GC9A01 display.  As with most ESP32 hookup diagrams, it is important to use the correct GPIO numbers instead of physical pins. The diagram shows the WROVER, so if you are using a different module you’ll need to consult its documentation to ensure that you hook it up properly.

The TFT_eSPI library is ideal for this, and several other, displays. You can install it through your Arduino IDE Library Manager, just search for “TFT_eSPI”.

The GC9A01 LCD module is a 1.28-inch round display that is useful for instrumentation and other similar projects. Today we will learn how to use this display with an Arduino Uno and an ESP32.

In this digital age, we come across LCDs all around us from simple calculators to smartphones, computers and television sets, etc. The LCDs use liquid crystals to produce images or texts and are divided into different categories based on different criteria like type of manufacturing, monochrome or colour, and weather Graphical or character LCD. In this tutorial, we will be talking about the 16X2 character LCD Modules.

The 16x2 LCDs are very popular among the DIY community. Not only that, but you can also find them in many laboratory and industrial equipment. It can display up to 32 characters at a time. Each character segment is made up of 40 pixels that are arranged in a 5x8 matrix. We can create alphanumeric characters and custom characters by activating the corresponding pixels. Here is a vector representation of a 16x2 LCD, in which you can see those individual pixels.

As the name indicates, these character segments are arranged in 2 lines with 16 characters on each line. Even though there are LCDs with different controllers are available, The most widely used ones are based on the famous HD44780 parallel interface LCD controller from Hitachi.

The 16x2 has a 16-pin connector. The module can be used either in 4-bit mode or in 8-bit mode. In 4-bit mode, 4 of the data pins are not used and in 8-bit mode, all the pins are used. And the connections are as follows:

Vo / VEE Contrast adjustment; the best way is to use a variable resistor such as a potentiometer. The output of the potentiometer is connected to this pin. Rotate the potentiometer knob forward and backwards to adjust the LCD contrast.

The 16x2 LCD modules are popular among the DIY community since they are cheap, easy to use and most importantly enable us to provide information very efficiently. With just 6 pins, we can display a lot of data on the display.

The module has 16 pins. Out of these 16 pins, two pins are for power, two pins are for backlight, and the remaining twelve pins are for controlling the LCD.

If you look at the backside of the module you can simply see that there are not many components. The main components are the two controller chips that are under the encapsulation. There is an onboard current limiting resistor for the backlight. This may vary from different modules from different manufacturers. The only remaining components are a few complimentary resistors for the LCD controller.

In the module PCB, you may have noticed some unpopulated footprints. These footprints are meant for charge pump circuits based on switched capacitor voltage converters like ICL7660 or MAX660. You can modify your LCD to work with 3.3V by populating this IC and two 10uF capacitors to C1 and C2 footprint, removing Jumper J1 and adding jumper J3. This modification will generate a negative contrast voltage of around 2.5V. This will enable us to use the LCD even with a VCC voltage of 3.3V.

To test whether a 16x2 LCD works or not, connect the VDD, GND and backlight pins to 5v and GND. Connect the centre terminal of a 10K variable resistor to the VEE pin. Connect the other two terminals to VCC and GND. Simply rotate the variable resistor you will see that the contrast will be adjusted and small blocks are visible. If these rectangles are visible, and you were able to adjust the contrast, then the LCD is working

There are 16 pins on the display module. Two of them are for power (VCC, GND), one for adjusting the contrast (VEE), three are control lines (RS, EN, R/W), eight pins are data lines(D0-D7) and the last two pins are for the backlight (A, K).

The 16x2 LCD has 32 character areas, which are made up of a 5x8 matrix of pixels. By turning on or off these pixels we can create different characters. We can display up to 32 characters in two rows.

Controlling the LCD module is pretty simple. Let’s walk through those steps. To adjust the contrast of the LCD, the Vo/ VEE pin is connected to a variable resistor. By adjusting the variable resistor, we can change the LCD contrast.

The RS or registry select pin helps the LCD controller to know whether the incoming signal is a control signal or a data signal. When this pin is high, the controller will treat the signal as a command instruction and if it’s low, it will be treated as data. The R/W or Read/Write pin is used either to write data to the LCD or to read data from the LCD. When it’s low, the LCD module will be in write mode and when it’s high, the module will be in reading mode.

The Enable pin is used to control the LCD data execution. By default, this pin is pulled low. To execute a command or data which is provided to the LCD data line, we will just pull the Enable pin to high for a few milliseconds.

To test the LCD module, connect the VDD, GND, and backlight pins to 5v and GND. Connect the center terminal of a 10K variable resistor to the VEE pin. Connect the other two terminals to VCC and GND as per the below connection diagram-

Simply rotate the variable resistor you will see that the contrast will be adjusted and small blocks are visible. If these rectangles are visible, and you were able to adjust the contrast, then the LCD is working.

Let’s see how to connect the LCD module to Arduino. For that first, connect the VSS to the GND and VDD to the 5V. To use the LCD backlight, connect the backlight Anode to the 5V and connect the backlight cathode to the GND through a 220Ωresistor. Since we are not using the read function connect the LCD R/W pin to the GND too. To adjust the contrast, connect the centre pin of a 10KΩ trimmer resistor to the VEE pin and connect the side pins to the VCC and GND. Now connect the registry select pin to D12 and Enable pin to D11.

Now let’s connect the data pins. The LCD module can work in two modes, 8-bit and 4-bit. 8-bit mode is faster but it will need 8 pins for data transfer. In 4-bit mode, we only need four pins for data. But it is slower since the data is sent one nibble at a time. 4-bit mode is often used to save I/O pins, while the 8-bit mode is used when speed is necessary. For this tutorial, we will be using the 4-bit mode. For that connect the D4, D5, D6 and D7 pins from the LCD to the D5, D4, D3 and D2 pins of the Arduino.

The following Arduino 16x2 LCD code will print Hello, World! on the first line of the display and the time the Arduino was running in seconds on the second line.

Now let’s discuss the code. As usual, the sketch starts by including the necessary libraries. For this tutorial, we will be including the LiquidCrystal library from Arduino. This library is compatible with LCDs based on the Hitachi HD44780, or any compatible chipset. You can find more details about this library on the Arduino website.

Let’s create an object to use with the LiquidCrystal library. The following line of code will create an object called lcd. We will be using this object in the entire code to access the library functions. The object is initialized with the pin numbers.

Now let’s look at the setup()function. The lcd.begin function is used to initialize the LCD module. This function will send all the initialization commands. The parameters used while calling this function are the number of columns and the number of rows. And the next function is lcd.print. with this function, we have printed the word Circuit Digest! to the LCD. Since the LCD cursor is set to home position within the lcd.begin, we don’t need to set any cursor position. This text will stay there for two seconds. After that, the text will scroll from left to right until the entire text is out of the display. To scroll the display to the right, we have used the function lcd.scrollDisplayRight. After that, to clear display, we used lcd.clear, this will clear any characters on the display.

Now let’s look at theloop function. The for loop will count from 0 to 9, and when it reaches 9, it will reset the count and repeat the process all over again. lcd.setCursor is used to set the cursor position. lcd.setCursor(8, 1) will set the LCD cursor to the eighth position in the second row. In the LCD, the first row is addressed as 0 and the second row is addressed as 1. And the lcd.print(i) will print the count value stored in the variable i to the display.

Wrong characters are displayed: This problem occurs usually when the LCD is not getting the correct data. Make sure you are sending the correct ASCII value. If you are sending the correct ASCII characters, but still showing the wrong one on the LCD, check your connections for loose contact or short circuits.

Contrast and delay are ok, but still no display: Make sure you are powering the LCD from a 5V source. By default, these displays won’t work with a supply voltage below 5V. So if you are using the display with a 3.3V microcontroller make sure to power the display from 5V and use level shifters in between the display and the microcontroller.

In this project we will provide the input voice using Google Voice Keyboard via a Android App (BlueTerm) and print the text on 16x2 LCD using Raspberry Pi.

In this tutorial we are interfacing a Liquid Crystal Display (LCD) module with the Raspberry Pi Pico using Micropython to display strings, and characters on the LCD.

We used some Python scripts to find the local IP address of your Raspberry Pi on the network and display it on the 16x2 LCD Screen. We also added the script in the Crontab so that it can be run on every 10 minutes and we will have the updated IP address every time.

To establish a good communication between human world and machine world, display units play an important role. And so they are an important part of embedded systems. Display units - big or small, work on the same basic principle. Besides complex display units like graphic displays and 3D dispays, one must know working with simple displays like 16x1 and 16x2 units. The 16x1 display unit will have 16 characters and are in one line. The 16x2 LCD will have 32 characters in total 16in 1st line and another 16 in 2nd line. Here one must understand that in each character there are 5x10=50 pixels so to display one character all 50 pixels must work together. But we need not to worry about that because there is another controller (HD44780) in the display unit which does the job of controlling the pixels. (you can see it in LCD unit, it is the black eye at the back ).

In this tutorial, we are going to interface a 16x2 LCD with ARDUINO UNO. Unlike normal development boards interfacing an LCD to an ARDUINO is quite easy. Here we don’t have to worry about data sending and receiving. We just have to define the pin numbers and it will be ready to display data on LCD.

Note:We updated this tutorial and added some more additional information along with a step-by-step guide to interface 16x2 LCD withArduino. You can follow the below link for an updated tutorial.

In 16x2 LCD there are 16 pins over all if there is a back light, if there is no back light there will be 14 pins. One can power or leave the back light pins. Now in the 14 pins there are 8 data pins (7-14 or D0-D7), 2 power supply pins (1&2 or VSS&VDD or GND&+5v), 3rd pin for contrast control (VEE-controls how thick the characters should be shown), and 3 control pins (RS&RW&E).

In the circuit, you can observe I have only took two control pins, this gives the flexibility. The contrast bit and READ/WRITE are not often used so they can be shorted to ground. This puts LCD in highest contrast and read mode. We just need to control ENABLE and RS pins to send characters and data accordingly.

The ARDUINO IDE allows the user to use LCD in 4 bit mode. This type of communication enables the user to decrease the pin usage on ARDUINO, unlike other the ARDUINO need not to be programmed separately for using it in 4 it mode because by default the ARDUINO is set up to communicate in 4 bit mode. In the circuit you can see we have used 4bit communication (D4-D7).

First we need to enable the header file (‘#include ’), this header file has instructions written in it, which enables the user to interface an LCD to UNO in 4 bit mode without any fuzz. With this header file we need not have to send data to LCD bit by bit, this will all be taken care of and we don’t have to write a program for sending data or a command to LCD bit by bit.

Second we need to tell the board which type of LCD we are using here. Since we have so many different types of LCD (like 20x4, 16x2, 16x1 etc.). Here we are going to interface a 16x2 LCD to the UNO so we get ‘lcd.begin(16, 2);’. For 16x1 we get ‘lcd.begin(16, 1);’.

In this instruction we are going to tell the board where we connected the pins. The pins which are connected need to be represented in order as “RS, En, D4, D5, D6, D7”. These pins are to be represented correctly. Since we have connected  RS to PIN0 and so on as show in the circuit diagram, we represent the pin number to board as “LiquidCrystal lcd(0, 1, 8, 9, 10, 11);”. The data which needs to be displayed in LCD should be written as “ cd.print("hello, world!");”. With this command the LCD displays ‘hello, world!’.

In this project, I will show you how to interface a 128X64 Graphical LCD with Arduino UNO. This particular LCD Module is based ST7920 LCD Controller. So, we will first see a little bit about the Graphical LCD Module and its LCD Controller ST7920.

In the previous Arduino project, I have interfaced a Nokia 5110 LCD Module with Arduino. It is also a graphical LCD which can display some basic bitmap images and graphics. But the issue with Nokia 5110 LCD Module is its resolution.

At 84 x 48 pixels, the Nokia 5110 LCD can be used for implementing a menu-based user interface. Due to its small size, the resulting menu will be limited to 3 or 4 items per page.

If we want a bigger display with more real estate to work with, then the obvious choice is to go for the bigger and better 128×64 Graphical LCD Module.

As a demonstration, after making all the hardware connections, I will display a bitmap image on the Graphical LCD Module. If you are interested in implementing a simple 16×2 Alpha-Numeric LCD with Arduino, then check out this tutorial.

At first glance, the 128×64 Graphical LCD Module seems like a bigger brother to the famous 16×2 LCD or 20×4 LCD Modules, with their similar construction and almost similar pin layout.

But there is a significant difference between those two. 16×2 or 20×4 LCDs are essentially character displays. They can only display alpha-numeric characters and some simple custom characters that are confined to a 5×8 matrix.

By using different combinations of pixels, we can basically display characters of various sizes. But the magic doesn’t end there. You can display images and graphics (small animations) as well. In a 128×64 LCD Module, there are 64 rows and 128 columns.

There are several versions of the Graphical LCD in the market. Even though the usage, application and implementations are almost identical, the main difference lies in the internal LCD Controller used to drive the dot matrix display.

Some of the commonly used LCD Controllers are KS0108, SSD1306, ST7920, SH1106, SSD1322, etc. The pin out of the final LCD Module might vary depending on the LCD Controller used. So, please verify the LCD Controller as well as the pin out before making a purchase.

The Graphical LCD Module I purchased consists of ST7920 Controller. It is manufactured by Sitronix and supports three types of bus interfaces i.e., 8-bit mode, 4-bit mode and Serial interface.

If you have used 16×2 LCD Display earlier, then you might be familiar with both 4-bit as well as 8-bit parallel interfaces. The serial interface is something new and we will explore this option in this project.

As I already mentioned, double-check with the manufacturer about the pinout of the Graphical LCD Module. The following table describes the pinout of the 128×64 LCD Module that I have.

Now that we have seen a little bit about the Graphical LCD and its controller ST7920, let us now proceed with interfacing the 128×64 Graphical LCD with Arduino. I will implement a simple circuit to demonstrate how easy it is to interface the LCD and Arduino using very few external components.

So, connect the RS, RW and E of the LCD to Digital IO pins 10, 11 and 13 of Arduino UNO. Also, in order to select the Serial Interface Mode, the PCB pin must be connected to GND.

The remaining connections are similar to a traditional 16×2 LCD. VCC and GND are connected to 5V and ground of the power supply. VO is connected to the wiper of a 10KΩ POT while the other two terminals of the POT are connected to 5V and GND respectively.

I have used the above “The Office” logo. Remember that the resolution of the 128×64 LCD is, well 128×64 pixels. So, the maximum image size should be 128×64. So, using Microsoft Paint, I have brought down the resolution of the above image to 128×64 pixels and also saved it as Monochrome Bitmap Image.

Before writing the code, you need to download a special library called “U8g2”. In the Arduino IDE, go to Tools -> Manage Libraries… Search for “u8g2” and install the latest version. It is a complex library and its github page consists of all the necessary documentation.

A simple project for interfacing the 128×64 Graphical LCD with Arduino is implemented here. Instead of displaying plain characters, I have displayed a bitmap image on the LCD to show its capability.

With the support of LiquidCrystal library, we even can use LCD WITHOUT knowing the meaning of these pins. However, if you are curious or want to know in-depth, let"s see these pins and their functionality:

Vo (LCD Contrast) pin: controls the contrast and brightness of the LCD, can be connected to 5V (the highest contrast and brightness), or connected to a potentiometer (to adjust to the contrast and brightness)

RS (Register Select) pin: There are two kinds of data that need to send to LCD: command (to control LCD) and data. These two are sent on the same data bus. RS pin tells the LCD whether the data on the data bus is the commands or the data.

8-bit mode is faster than the 4-bit mode, but use more pins than 4-bit mode. The mode selection is performed at the initialization process by sending a command to LCD.

Controlling LCD is a quite complicated task. Fortunately, thanks to the LiquidCrystal library, this library simplifies the process of controlling LCD for you so you don"t need to know the low-level instructions. You just need to connect Arduino to LCD and use the functions of the library. The using LCD is a piece of cake.