arduino lcd screen tutorial pricelist

Currently I have code to swipe in rfid tags to a reader which then using the arduino Uno it lights up an LED coordinating to which tag was swiped. What I"m looking to do now is set a dollar amount to each tag and once a tag is swiped in add it to like a current total price and then output that to LCD Screen. Is this possible with Arduino Uno? Anyone help with this?

In this Arduino touch screen tutorial we will learn how to use TFT LCD Touch Screen with Arduino. You can watch the following video or read the written tutorial below.

For this tutorial I composed three examples. The first example is distance measurement using ultrasonic sensor. The output from the sensor, or the distance is printed on the screen and using the touch screen we can select the units, either centimeters or inches.

The third example is a game. Actually it’s a replica of the popular Flappy Bird game for smartphones. We can play the game using the push button or even using the touch screen itself.

As an example I am using a 3.2” TFT Touch Screen in a combination with a TFT LCD Arduino Mega Shield. We need a shield because the TFT Touch screen works at 3.3V and the Arduino Mega outputs are 5 V. For the first example I have the HC-SR04 ultrasonic sensor, then for the second example an RGB LED with three resistors and a push button for the game example. Also I had to make a custom made pin header like this, by soldering pin headers and bend on of them so I could insert them in between the Arduino Board and the TFT Shield.

Here’s the circuit schematic. We will use the GND pin, the digital pins from 8 to 13, as well as the pin number 14. As the 5V pins are already used by the TFT Screen I will use the pin number 13 as VCC, by setting it right away high in the setup section of code.

I will use the UTFT and URTouch libraries made by Henning Karlsen. Here I would like to say thanks to him for the incredible work he has done. The libraries enable really easy use of the TFT Screens, and they work with many different TFT screens sizes, shields and controllers. You can download these libraries from his website, RinkyDinkElectronics.com and also find a lot of demo examples and detailed documentation of how to use them.

After we include the libraries we need to create UTFT and URTouch objects. The parameters of these objects depends on the model of the TFT Screen and Shield and these details can be also found in the documentation of the libraries.

Next we need to define the fonts that are coming with the libraries and also define some variables needed for the program. In the setup section we need to initiate the screen and the touch, define the pin modes for the connected sensor, the led and the button, and initially call the drawHomeSreen() custom function, which will draw the home screen of the program.

So now I will explain how we can make the home screen of the program. With the setBackColor() function we need to set the background color of the text, black one in our case. Then we need to set the color to white, set the big font and using the print() function, we will print the string “Arduino TFT Tutorial” at the center of the screen and 10 pixels  down the Y – Axis of the screen. Next we will set the color to red and draw the red line below the text. After that we need to set the color back to white, and print the two other strings, “by HowToMechatronics.com” using the small font and “Select Example” using the big font.

Now we need to make the buttons functional so that when we press them they would send us to the appropriate example. In the setup section we set the character ‘0’ to the currentPage variable, which will indicate that we are at the home screen. So if that’s true, and if we press on the screen this if statement would become true and using these lines here we will get the X and Y coordinates where the screen has been pressed. If that’s the area that covers the first button we will call the drawDistanceSensor() custom function which will activate the distance sensor example. Also we will set the character ‘1’ to the variable currentPage which will indicate that we are at the first example. The drawFrame() custom function is used for highlighting the button when it’s pressed. The same procedure goes for the two other buttons.

So the drawDistanceSensor() custom function needs to be called only once when the button is pressed in order to draw all the graphics of this example in similar way as we described for the home screen. However, the getDistance() custom function needs to be called repeatedly in order to print the latest results of the distance measured by the sensor.

Here’s that function which uses the ultrasonic sensor to calculate the distance and print the values with SevenSegNum font in green color, either in centimeters or inches. If you need more details how the ultrasonic sensor works you can check my particular tutorialfor that. Back in the loop section we can see what happens when we press the select unit buttons as well as the back button.

Ok next is the RGB LED Control example. If we press the second button, the drawLedControl() custom function will be called only once for drawing the graphic of that example and the setLedColor() custom function will be repeatedly called. In this function we use the touch screen to set the values of the 3 sliders from 0 to 255. With the if statements we confine the area of each slider and get the X value of the slider. So the values of the X coordinate of each slider are from 38 to 310 pixels and we need to map these values into values from 0 to 255 which will be used as a PWM signal for lighting up the LED. If you need more details how the RGB LED works you can check my particular tutorialfor that. The rest of the code in this custom function is for drawing the sliders. Back in the loop section we only have the back button which also turns off the LED when pressed.

In order the code to work and compile you will have to include an addition “.c” file in the same directory with the Arduino sketch. This file is for the third game example and it’s a bitmap of the bird. For more details how this part of the code work  you can check my particular tutorial. Here you can download that file:

In this guide we’re going to show you how you can use the 1.8 TFT display with the Arduino. You’ll learn how to wire the display, write text, draw shapes and display images on the screen.

The 1.8 TFT is a colorful display with 128 x 160 color pixels. The display can load images from an SD card – it has an SD card slot at the back. The following figure shows the screen front and back view.

This module uses SPI communication – see the wiring below . To control the display we’ll use the TFT library, which is already included with Arduino IDE 1.0.5 and later.

The TFT display communicates with the Arduino via SPI communication, so you need to include the SPI library on your code. We also use the TFT library to write and draw on the display.

In which “Hello, World!” is the text you want to display and the (x, y) coordinate is the location where you want to start display text on the screen.

The 1.8 TFT display can load images from the SD card. To read from the SD card you use the SD library, already included in the Arduino IDE software. Follow the next steps to display an image on the display:

In this guide we’ve shown you how to use the 1.8 TFT display with the Arduino: display text, draw shapes and display images. You can easily add a nice visual interface to your projects using this display.

In this tutorial, we will display the custom characters on an LCD 16×2. Liquid crystal display (LCDs) offer a convenient and inexpensive way to provide a user interface for a project.

By far the most popular LCD used is the text panel based on the Hitachi HD44780 chip. This displays two or four lines of text, with 16 or 20 characters per line (32 and 40 character versions are also available, but usually at much higher prices).

We want to define and display custom characters or symbols (glyphs) that we have created. The symbols we want to display are not predefined in the LCD character memory.

A library for driving text LCD displays is provided with Arduino, and you can print text on your LCD easily as on the serial monitor because of LCD and serial share the same underlying print function.

To display custom characters on LCD, we must first know about the LCD dot matrix means pixels in LCD. There are 5 pixels in rows and 8 pixels in columns means every character is a combination of 5*8 dots.

The LiquidCrystal library enables you to create up to eight custom characters, which can be printed as character codes 0 through 8. Each character on the screen is drawn on a grid of 5 x 8 pixels.

Now We want to combine two or more custom characters to print larger fonts / double-height characters than a single character; for example, double-height numbers on the screen.

Each big number is built from six of these glyphs, three forming the upper half of the big digit and three forming the lower half. BiDigitsTop and bigDigitsBot are arrays defining which custom glyph is used for the top and bottom rows on the LCD screen.

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.

You can find the previous article here. It contains a description of the LCD module, shows you how to connect the display to your Arduino UNO board and describes the basic rules of operating it using the software. Still, it needs to be admitted here that there is only a limited number of applications for an LCD alone, because in the case of such a simple LCD module no settings can be entered. To do so, you need a keyboard, which we will discuss in detail in one of the future articles, but now let us use a ready-made solution from the Arduino ecosystem – a board from Olimex – SHIELDLCD16x2.

This is a shield board which extends Arduino capabilities, equipped with an LCD module (2 lines of 16 characters each), 4 buttons and 8 additional GPIO lines. On the board, there is a PIC processor which communicates with Arduino UNO via the TWI interface. With access to a library of functions, operating this module with a built-in microcontroller should not cause any major problems. Let"s start with preparing the module for operation.

There are two steps to prepare the module for work: hardware and software. The first one is simply to plug the shield into the Arduino UNO board. The second one requires you to install a library of module operating functions.

To install the library, go to the module manufacturer"s website i.e. Olimex. Then, in the search box (next to the Search button) enter the part of the module name "LCD16x2". (Figure 1). Click on the Search button. When this text was being created, the search retuned two results – please, select "SHIELD-LCD16x2".

Under the description of the module, you can find the "SOFTWARE" section (figure 2). Each line of text in this section is also a link to a file that can be downloaded from the Olimex website. At this point, we are looking for the link saying: "OLIMEXINO-328 + SHIELD-LCD16x2 – a library and set of demo examples".

Download the ZIP file available at this link to your computer. Of course, it is worth having a look at the available examples, but for our needs it is enough to install the library saved in the LCD16x2 catalogue.

The Arduino IDE allows for various different ways of installing libraries. In this case, the easiest way is to upload the sources to the project directory, which also contains a libraries subdirectory. The project directory is created during the installation of Arduino IDE, and Windows usually places it (in the Polish language version) in subdirectory Ten Komputer → Dokumenty → Arduino. To add the library sources to today"s example, just move the LCD16x2 directory to the libraries folder. Once you"ve done that, launch the Arduino IDE.

Before getting started with your own program, you should read examples of using the LCD16x2.h library of functions available in the Examples directory. It is a much more effective method of learning than reading documentation, although it is worth remembering about the latter as well.

As mentioned before, the shield communicates with the UNO board using a serial interface. It"s easy to guess that the functions described in the previous article must be modified, because they used a parallel, 4-bit interface. As you can imagine, the microcontroller on the shield board communicates with the LCD character display module in the same way, but our Arduino UNO cannot "see" the display, and the control is done indirectly. Therefore, start the program by adding libraries to support the appropriate serial interface and the display module mounted on the shield board.

To make it simple, in order not to use the long library name, it is recommended to assign to it the lcd alias. We will use it by writing the name of the library function after the dot.

As you remember from the previous article, programs created for Arduino are divided into two parts: the initialization function and the infinite loop. The commands of the first one are written in the void setup() function, and of the latter – in the void loop() function. The commands contained within the setup function are executed only once, while those within the infinite loop are executed throughout the program.

The initialization function starts the TWI interface, clears the LCD screen, and turns on the display backlight at the maximum LED light intensity (0 parameter turns off the backlight).

Mask 0x01 corresponds to the first button on the left, while 0x08 corresponds to the first button on the right. The program numbers the buttons by giving the pressed variable a value corresponding to the conventional button number. Then, this number is shown on the LCD screen, at the position starting in the first row and the first column. The message is displayed only if the pressed value is different from 0. Otherwise, the message "No button" is displayed, indicating that no button is pressed. The message is terminated with three spaces so that when overlaid on "1 is pressed" (which is longer) the last characters of the caption are cleared.

The whole sketch is available in the resources attached to the article. Compile it and upload it to the Arduino UNO microcontroller memory using the Ctrl+U shortcut (Sketch → Upload).

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.

BONUS: I made a quick start guide for this tutorial that you can download and go back to later if you can’t set this up right now. It covers all of the steps, diagrams, and code you need to get started.

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:

This function places the cursor in the upper left hand corner of the screen, and prints any subsequent text from that position. For example, this code replaces the first three letters of “hello world!” with X’s:

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 (°):

Using a display is a common need to have data visualization for projects including mobile screen. I2C 16X2 Liquid Crystal Character LCD Display is one of most used device and can be interfaced to Arduino Uno by using Arduino IDE

Liquid crystal display is an important part of a system and it helps to display the different constraints of the project. There are many types of LCD displays are available in the market and they can be easily identified by the interface; most of the LCD displays have ten pin interfaces and require appropriate cabling and code. The I2C LCD display has compatible driver circuitry of PCF8574 I2C chip which make simpler the cabling phase.

The most common family of LCD is 16×2 characters LCD which has sixteen columns and two rows of the characters and these can be effectively programmed in an Arduino environment. The pictorial view of the 16×2 LCD is shown in the figure.

In this tutorial, the focus of the work is character LCD. The word characters mean that alphabets (A, B, C… Z, a, b, … z and symbols) and decimals (1,2,3) can be displayed on this LCD. Other graphics like graphs, waveforms are not able to be displayed on it.

I2C LCD contains 4 pins, which are VCC, GND, SCL and SDA. SCL and SDA are dedicated to i2C communication. Every microcontroller has dedicated pins of I2C. For Arduino Uno are A4 (SDA) and A5 (SCL).

Connect your PC to Arduino and open Arduino IDE. For the very first steps, you can refer to Connecting Connecting Windows PC with Arduino tutorial. Download the “arduinoLCD” code and library from this link

Extract the folder from your PC. You will have a folder named “arduinoLCD” containing a file named “arduinoLCD.ino”. Open this file with your Arduino IDE.

This is the section before setup which is used for globe variables defining and libraries additions. Wire.h is the library for I2C two-wire communication, Liquid_crystal_I2C is an LCD library that communicates in the I2C communication protocol. Child of the library is created in the third line, which defines 0x27 as the i2c address, 16 are the columns while 2 are the rows. If you have a 20X4 LCD, just write down 20 by replacing 16 and 4 by changing 2.

This is the setup section in which LCD is initialised by lcd.begin() command, while LCD contains a light that can be turned on and off. When lcd.backlight is initialised, it turns ON the LCD lights. Character LCD comes in blue and yellow backlights.

In the loop section, LCD cursors are defined at which character needs to be written, lcd.setCursor (0,0) means cursor should be at the location of column 0 and row 0. lcd.print(“Seconds”) deals the seconds as a string and directly print it. If what is written is lcd.print(seconds), without double commas, the code will consider it as a variable, which should be defined.

Lcd.print(millis()/1000) where millis() is the time of the program when the Arduino board started, dividing by 1000 means milliseconds converted to seconds.

From your Arduino IDE, compile the code. Once compile operation has finished successfully, load it in your Arduino and the LCD Display will start showing with Arduino as in the following picture: