i2c 16x2 lcd module free sample

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.

The LiquidCrystal_I2C is available from GitHub. When visiting the GitHub page, select the Code button and from the drop-down menu, choose Download ZIP option to save the file to a convenient location on your workstation.

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.

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.

This tutorial shows how to use the I2C LCD (Liquid Crystal Display) with the ESP32 using Arduino IDE. We’ll show you how to wire the display, install the library and try sample code to write text on the LCD: static text, and scroll long messages. You can also use this guide with the ESP8266.

Additionally, it comes with a built-in potentiometer you can use to adjust the contrast between the background and the characters on the LCD. On a “regular” LCD you need to add a potentiometer to the circuit to adjust the contrast.

Before displaying text on the LCD, you need to find the LCD I2C address. With the LCD properly wired to the ESP32, upload the following I2C Scanner sketch.

After uploading the code, open the Serial Monitor at a baud rate of 115200. Press the ESP32 EN button. The I2C address should be displayed in the Serial Monitor.

Displaying static text on the LCD is very simple. All you have to do is select where you want the characters to be displayed on the screen, and then send the message to the display.

In this simple sketch we show you the most useful and important functions from the LiquidCrystal_I2C library. So, let’s take a quick look at how the code works.

The next two lines set the number of columns and rows of your LCD display. If you’re using a display with another size, you should modify those variables.

Scrolling text on the LCD is specially useful when you want to display messages longer than 16 characters. The library comes with built-in functions that allows you to scroll text. However, many people experience problems with those functions because:

In a 16×2 LCD there are 32 blocks where you can display characters. Each block is made out of 5×8 tiny pixels. You can display custom characters by defining the state of each tiny pixel. For that, you can create a byte variable to hold  the state of each pixel.

In summary, in this tutorial we’ve shown you how to use an I2C LCD display with the ESP32/ESP8266 with Arduino IDE: how to display static text, scrolling text and custom characters. This tutorial also works with the Arduino board, you just need to change the pin assignment to use the Arduino I2C pins.

In this Arduino LCD I2C tutorial, we will learn how to connect an LCD I2C (Liquid Crystal Display) to the Arduino board. LCDs are very popular and widely used in electronics projects for displaying information. There are many types of LCD. This tutorial takes LCD 16x2 (16 columns and 2 rows) as an example. The other LCDs are similar.

In the previous tutorial, we had learned how to use the normal LCD. However, wiring between Arduino and the normal LCD is complicated. Therefore, LCD I2C has been created to simplify the wiring. Actually, LCD I2C is composed of a normal LCD, an I2C module and a potentiometer.

lcd.print() function supports only ASCII characters. If you want to display a special character or symbol (e.g. heart, angry bird), you need to use the below character generator.

Depending on manufacturers, the I2C address of LCD may be different. Usually, the default I2C address of LCD is 0x27 or 0x3F. Try these values one by one. If you still failed, run the below code to find the I2C address.

The CFA533-***-KC series is a 16x2 I2C LCD with keypad. The I2C interface allows you to use just two lines (SDA & SCL) to have bi-directional communication with the I2C LCD. Other devices can also share those two I2C control lines with the LCD. Only 4 wires are needed to connect this I2C LCD: power, ground, SDA (I2C Serial DAta) and SCL (I2C Serial CLock).

The CFA533 can run on 3.3v to 5.0v directly, with no changes needed, so you do not need to do any level translation between your embedded processor and the I2C LCD. Simply power the CFA533 from the same supply as your processor and the I2C signal levels will match up.

Using only one address on your I2C bus, you can add all the elements that you need for your front panel. The CFA533 I2C LCD can also read up to 32 DS18B20 digital temperature sensors, giving you an easy way to integrate temperature sensing over the I2C bus. No additional firmware or pins are needed on the host system.

This CFA533-TFH variant features crisp dark letters against a white, backlit background. The keypad has a matching white LED backlight. Since the LCD is a backlit positive FSTN, the CFA533-TFH I2C LCD is readable in direct sunlight, as well as complete darkness.

This 2×16 character LCD Module with BLUE Backlight uses an I2C interface to communicate with the host microcontroller. This budget-conscious LCD is used on projects requiring the display of text, data, or ASCII characters of all types. Connect to Vcc, Gnd, SDA (serial data line), and SCL (serial clock line). This is a 5VDC device and will be found on the I2C bus at address 0x27 / 0x3F.

If you’ve ever attempted to connect an LCD display to an Arduino, you’ve probably noticed that it uses a lot of Arduino pins. Even in 4-bit mode, the Arduino requires seven connections – half of the Arduino’s available digital I/O pins.

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

As the name suggests, these LCDs are ideal for displaying only characters. A 16×2 character LCD, for example, can display 32 ASCII characters across two rows.

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 have multiple devices on the same I2C bus, you may need to set a different I2C address for the LCD adapter to avoid conflicting with another I2C device.

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

According to the Texas Instruments’ datasheet, the three address selection bits (A0, A1, and A2) are located at the end of the 7-bit I2C address register.

According to the NXP Semiconductors’ datasheet, the three address selection bits (A0, A1, and A2) are located at the end of the 7-bit I2C address register. However, the remaining bits in the address register are different.

So the I2C address of your LCD is most likely 0x27 or 0x3F. If you’re not sure what your LCD’s I2C address is, there’s an easy way to figure it out. You’ll learn about that later in this tutorial.

Now we are left with the pins that are used for I2C communication. Note that each Arduino board has different I2C pins that must be connected correctly. 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 referred to as A5 (SCL) and A4 (SDA).

After wiring the LCD, you will need to adjust the contrast of the LCD. On the I2C module, there is a potentiometer that can be rotated with a small screwdriver.

Now, turn on the Arduino. You will see the backlight light up. As you turn the potentiometer knob, the first row of rectangles will appear. If you have made it this far, Congratulations! Your LCD is functioning properly.

Before you can proceed, you must install the LiquidCrystal_I2C library. This library allows you to control I2C displays using functions that are very similar to the LiquidCrystal library.

Filter your search by entering ‘liquidcrystal‘. Look for the LiquidCrystal I2C library by Frank de Brabander. Click on that entry and then choose Install.

As previously stated, the I2C address of your LCD depends on the manufacturer. If your LCD has a PCF8574 chip from Texas Instruments, its I2C address is 0x27; if it has a PCF8574 chip from NXP Semiconductors, its I2C address is 0x3F.

If you’re not sure what your LCD’s I2C address is, you can run a simple I2C scanner sketch that scans your I2C bus and returns the address of each I2C device it finds.

However, before you upload the sketch, you must make a minor change to make it work for you. You must pass the I2C address of your LCD as well as the display dimensions to the LiquidCrystal_I2C constructor. If you’re using a 16×2 character LCD, pass 16 and 2; if you’re using a 20×4 character LCD, pass 20 and 4.

The next step is to create an object of LiquidCrystal_I2C class. The LiquidCrystal_I2C constructor accepts three inputs: I2C address, number of columns, and number of rows of the display.

In the setup, three functions are called. The first function is init(). It initializes the interface to the LCD. The second function is clear(). This function clears the LCD screen and positions the cursor in the upper-left corner. The third function, backlight(), turns on the LCD backlight.

The function setCursor(2, 0) is then called to move the cursor to the third column of the first row. The cursor position specifies where you want the new text to appear on the LCD. It is assumed that the upper left corner is col=0 and row=0.

There are many useful functions you can use with LiquidCrystal_I2C Object. Some of them are listed below:lcd.home() function positions 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 the above function, use this inside a for loop for continuous scrolling.

lcd.display() function turns on the LCD display, after it’s been turned off with noDisplay(). This will restore the text (and cursor) that was on the display.

The CGROM stores the font that appears on a character LCD. When you instruct a character LCD to display the letter ‘A’, it needs to know which pixels to turn on so that we see an ‘A’. This data is stored in the CGROM.

CGRAM is an additional memory for storing user-defined characters. This RAM is limited to 64 bytes. Therefore, for a 5×8 pixel LCD, only 8 user-defined characters can be stored in CGRAM, whereas for a 5×10 pixel LCD, only 4 can be stored.

There’s no limit to what you can create. The only limitation is that the LiquidCrystal_I2C library only supports eight custom characters. But don’t be sad, look at the bright side; at least we have eight characters.

After including the library and creating the LCD object, custom character arrays are defined. The array consists of 8 bytes, with each byte representing a row in a 5×8 matrix.

The Biomaker Stage-2 component pack contains a liquid crystal display (LCD) capable of displaying 2 lines of 16 characters (right). The device is equipped with an I2C interface backpack, that allows serial communication with the device. (This is the black-coloured circuit board soldered to the back of the green-coloured LCD board). The I2C interface allows communication with the LCD screen through two wires plus power supply, rather than 8+ wires required by a parallel port device. The I2C protocol allows comunication with multiple devices on the same 2 wire bus. Each device needs a unique address, usually set in the hardware.

The LCD display is powered by a 5V supply and draws about 25mA with the backlight on, and 2mA without. The green coloured backlight sits behind black coloured characters. The characters are formed in two lines of 16 characters in 5x7 dot matrices.

The display should be connected to the microcontroller via the Vcc (5V), Gnd (ground), SDA (data) and SCL (clock) wires. Because it is common to use multiple I2C devices, it is generally easier to connect through the breadboard, which allows multiple devices to share the I2C signals and power from the relevant sockets on the yellow connector on the microcontroller board.

XOD provides the software node text-lcd-16x2-i2c, that allows direct communication with the display, with inputs for each line of the display (see below). The address of the i2C device should be set at 27h using the ADDR parameter.

Advanced use: If you which to use multiple LCD displays on the I2C bus, you can add solder bridges to the jumpers A0, A1 and A2 on the I2C backpack - in order to change the address of each device, and allow them to be individually addressed. The supplied I2C backpack has a PCF8574T chip: and the IC address is (high order first) 0100 A2 A1 A0. When shipped, A2~A0 are all vacant. The default I2C address therefore: 0100 111 (0x27). If you want to modify the address yourself add the relevant jumpers, noting that floating address pad is 1, and the short circuit is 0 after adding a solder bridge.

Important: There is a potentiometer that controls the contrast setting of the display. It is a controlled by a black plastic wheel at the front left edge of the LCD screen. (Contrast can also be adjusted using the blue potentiometer on the I2C backpack). The contrast setting requires fine adjustment, and the screen will appear blank and unresponsive if badly adjusted. If, on first use, you want to check that the LCD screen is correctly connected (i.e. are using the correct I2C address), use a XOD node to switch the backlight on and off. If that works, load some text into the screen, and adjust the contrast for best legibility.

In this tutorial, you’ll learn how to interface ESP32 with an LCD display 16×2 without I2C. It can be useful in some projects, however, it’s not very common, due to the GPIO pins it does consume. But it’s going to be a good starting point if you’re new to Alphanumeric LCDs in general or just want to use the generic Arduino LiquidCrystal display library.

Alphanumeric LCD 16×2 display units are the most common and easiest solutions to get some data out of your microcontroller to the world to visually see. It’s a very cheap, easy to use, and reliable option to display strings of text/numbers to your system’s users.

The only downside to using the bare 16×2 LCD display is that it requires 6 dedicated GPIO pins of your microcontroller. In the case of our ESP32, it can be really annoying to lose 6 GPIO pins for adding only 1 LCD module to the project. However, in some projects, it can be a good option in case you don’t need the extra GPIO pins anyway.

The second most commonly preferred option is by using the I2C module with your LCD. This will reduce the GPIO pins requirement down to only 2 pins (the I2C pins SDA & SCL). Not only that, actually the 2 pins of that I2C bus can still access so many other I2C devices on the exact same bus.

You can end up having maybe 5 LCDs connected to your microcontroller using only 2 pins If you’re using that I2C module. But it’s the topic of the next tutorial. For this tutorial, we’ll be doing bare LCD interfacing in a classic way without an I2C IO expansion module.

This is the pinout for a typical LCD 16×2 display unit. It’s got 8 data lines (you can use only 4 of them or all of the 8). And remember that it needs to be powered from a +5v source despite the fact that our ESP32 is a 3.3v microcontroller device. This requirement is only for the power supply pins, not the data lines.

There are two ways to interface the LCD diver (controller) IC. You can use the full bus width (8-Bits) for data or alternatively you can use a 4-Bit interface for a reduced pin count needed to control the LCD. Specifically low pin count MCUs need to operate in the 4-Bit mode. And it’s the case for our ESP32 which has limited resources in terms of GPIO pin count.

The differences between 8-Bit mode and 4-Bit mode are that in the 8-Bit mode you’re operating the LCD at the full speed. While in 4-Bit mode, you send each data byte or command in two consecutive cycles instead of one. The other difference is the initialization routine steps. This is detailed in the full LCD article linked below.

If you’re interested in learning more about the LCD display, how it works, how does the LCD driver IC work (the circular black thing on the back), its internal registers, and more. Then, you should check outthis tutorial linked down below.

In that tutorial, we’ll be scrolling through the LCD driver datasheet, learning how it works, how to write a driver firmware library for it, and build our own library in Embedded-C with PIC microcontrollers from scratch and test it out in a couple of LABs.

In this section, I’ll give you a brief description of the LiquidCrystal library that we’ll be using in this tutorial. And it’s basic API functions to initialize and write some text on any LCD. We’ll be using the generic LiquidCrystal library (not the I2C version) which is similar to any other Arduino LCD example code you’ve seen online.

The Arduino LiquidCrystal library gives you all the functionalities that you’d need from an LCD driver and it’s very easy to use in your projects. Here are the exact steps you need to follow in order to initialize and write to an LCD in your project code (in Arduino IDE).

Step2– Create an LCD object. In which you’ll define the GPIO pins to be used for the various LCD signals (6 pins). This is done in code as shown below

Step3– Now, you need to initialize the LCD in the Setup function, and it’s better to clear the display to make sure there are no random characters on the visible display. In this step, you also define the number of rows and columns for your display. There are many versions of this LCD display not only 16×2, there are 16×4, 20×4, and maybe others.

Step4– Now, our LCD is properly initialized and ready for displaying any data or executing any commands. To write something on the LCD you can use the LCD_object.print() function. As you can see in the example code down below

We use the LCD_object.setCursor() function to set the cursor position, so the next LCD write operation occurs exactly at that location. And that’s it! Here is how it looks like in real-life testing.

The diagram down below shows you the connection between ESP32 and the LCD 16×2 display (in 4-Bit data mode). Note that the LCD requires a +5v supply and the ESP32 is a 3.3v board, however, it’s got the USB Vbus available on the Vin pin. So, we’ll be using the Vin pin as a +5v source (it’s measured to be 4.7v but it’s sufficient indeed).

The code example down below does the following: We start with including the LiquidCrystal library, then create an LCD object and initialize it. Then, we’ll write to the home position “Hello World!”, and move the cursor to the middle of the 2nd row and write “GG izi”. And nothing to be done in the main loop() function.

The LCD display’s controller (Hitachi HD44780) supports up to 8 custom characters that you can create and store on the LCD itself. Then you can send the Index of each custom character to be displayed later. Maybe 8 custom characters are not enough for your project, but it’s one little extra feature that you can occasionally use.

ERM1602SYG-1 is big 16 characters wide,2 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.

This repository contains all the code for interfacing with a 16x2 character I2C liquid-crystal display (LCD). This accompanies my Youtube tutorial: Raspberry Pi - Mini LCD Display Tutorial.

During the installation, pay attention to any messages about python and python3 usage, as they inform which version you should use to interface with the LCD driver. For example:

It is possible to define in CG RAM memory up to 8 custom characters. These characters can be prompted on LCD the same way as any characters from the characters table. Codes for the custom characters are unique and as follows: