ili9325 tft lcd touchscreen display module free sample

Note: Please make sure HY32D is the right LCD display panel you need before buying, mainly based on the model, brand, and the appearance to judge, some lcd display panels have the same model name, but with different appearance, example the position of the screw hole, so please carefully confirm if this is the right accessory you need. If you don"t find the right product on our website or need any help, feel free to contact us at any time.

Touchscreen displays are everywhere! Phones, tablets, self-serve kiosks, bank machines and thousands of other devices we interact with make use of touchscreen displays to provide an intuitive user interface.

Today we will learn how touchscreens work, and how to use a common inexpensive resistive touchscreen shield for the Arduino.  Future videos and articles will cover capacitive touchscreens, as well as a touchscreen HAT for the Raspberry Pi.

Although touchscreens seem to be everywhere these days we tend to forget that just a few decades ago these devices were just science fiction for most of us. For many people, the touchscreen concept was introduced 30 years ago in the television seriesStar Trek: The Next Generation.

Eric A Johnson, a researcher at the Royal Radar Establishment in Malvern UK is credited for describing and then prototyping the first practical touchscreen. HIs device was a capacitive touchscreen, and it’s first commercial use was on air traffic control screens. However, the touchscreens used then were not transparent, instead, they were mounted on the frame of the CRT display.

In 1972, a group at the University of Illinois filed for a patent on an optical touchscreen. This device used a 16×16 array of LEDs and phototransistors, mounted on a frame around a CRT display. Placing your finger, or another solid object, on the screen would break two of the light beams, this was used to determine the position and respond accordingly.

The first transparent touchscreen was developed atCERNin 1973. CERN is also home to the Large Hadron Collider, and this is where Tim Berners-Lee invented the World Wide Web.

The first resistive touchscreen was developed by American inventor George Samuel Hurst in 1975, although the first practical version was not produced until 1982.

In 1982 theUniversity of Toronto’sInput Research Group developed the first multi-touch touchscreen, a screen that could interpret more than one touch at the same time.  The original device used a video camera behind a frosted piece of glass. Three years later the same group developed a multi-touch tablet that used a capacitive touchscreen instead.

The first commercial product to use a touchscreen was a point-of-sale terminal developed by Atari and displayed at the 1986 COMDEX expo in Las Vegas. The next year Casio launched theCasio PB-1000 pocket computerwith a touchscreen consisting of a simple 4×4 matrix.

LG created the world’s first capacitive touchscreen phone, theLG Pradaused a capacitive touchscreen and was released in early 2007. A few weeks later Apple released its first iPhone.

Most early touchscreen devices were resistive, as this technology is generally less expensive than capacitive screens. However, nowadays capacitive screens are more common, being used in the majority of smartphones and tablets.

Although they were invented after capacitive touchscreens, resistive touchscreens are probably the most common type used by hobbyists. The reason for that is the price and performance, resistive touchscreens are cheaper than capacitive ones and they are generally more accurate.

A resistive touchscreen consists of two thin layers of material, separated by a tiny gap.  Spacers are used to maintain the gap and keep the two sheets apart.

In a 4-Wire Analog touchscreen, there are two electrodes or “busbars” on each of the conductive layers.  On one layer these electrodes are mounted on the two X-axis sides, the other layer has them on the two y-axes.

This is the most inexpensive method of designing a resistive touchscreen. The touchscreen display that we will be working with today uses this arrangement.

In a 5-Wire Analog touchscreen, there are four wires, one connected to a circular electrode on each corner of the bottom layer. A fifth wire is connected to a “sensing wire”, which is embedded in the top layer.

This 8-Wire Analog touchscreen uses an arrangement of electrodes identical to the 4-Wire variety. The difference is that there are two wires connected to each electrode, one to each end.

Capacitive touchscreens are actually older technology than resistive displays.  They are commonly used in phones and tablets, so you’re probably familiar with them.

The capacitive touchscreen makes use of the conductivity of the human body. The touchscreen itself consists of a glass plate that has been treated with a conductive material.

The surface capacitive touchscreen is the most inexpensive design, so it is widely used. It consists of four electrodes placed at each corner of the touchscreen, which maintain a level voltage over the entire conductive layer.

This is a more advanced touchscreen technique. In a projected capacitive touchscreen transparent electrodes are placed along the protective glass coating and are arranged in a matrix.

The module we will be experimenting with today is a very common Arduino Shield, which is rebranded by many manufacturers. You can easily find these on Amazon, eBay or at your local electronics shop.

You can also just use the shield as an LCD display and ignore the two other components, however, if you intend on doing that it would be cheaper just to buy an LCD display without any touchscreen features.

This is a TFT orThin Film Transistordevice that uses liquid crystals to produce a display.  These displays can produce a large number of colors with a pretty decent resolution.

You do need to be looking directly at the display for best color accuracy, as most of these inexpensive LCD displays suffer from distortion and “parallax error” when viewed from the side. But as the most common application for a device like this is as a User Interface (UI) this shouldn’t be a problem.

This shield uses a 4-wire analog resistive touchscreen, as described earlier.  Two of the wires (one X and one Y) are connected to a couple of the analog inputs on the Arduino. The analog inputs are required as the voltage levels need to be measured to determine the position of the object touching the screen.

The microSD card socket is a convenience, it’s normally used for holding images for the display but it can also be used for program storage.  This can be handy for holding things like calibration settings and favorite selections.

The last paragraph regarding the microSD card may make you think that an Arduino Uno is the best choice for the Touchscreen Display Shield.  And it you require the microSD card then it probably is a good choice.

As there are three devices on the shield you will need libraries for each of the ones you want to use.  TheSD Libraryis already installed in your Arduino IDE, so you will just need libraries for the display and touchscreen.

For the LCD you will have a lot of choices in libraries. Most of these shields come with a CD ROM with some sketches and libraries, so you can use the LCD libraries there. Bear in mind however that code on these CD ROMs tends to be a little dated, you may have better lick on the vendors website.

This useful resource contains code, libraries and datasheets for a wealth of LCD displays, both touchscreen and non-touchscreen. You’ll also find code for some common OLED displays as well.

I ran my touchscreen through all of the code samples I obtained from the LCD Wiki. It’s an interesting exercise, and by examining the sketch for each demo you can learn a lot about programming the display.

This test does not make use of any of the extra libraries, it drives the LCD directly. It is only a test of the LCD display, it does not make use of the touchscreen membrane.

This example does use the custom libraries, and is a very good way to learn how to use them.  You’ll note that theLCDWIKI_GUI.hlibrary is loaded, which is the graphics library for the LCD display.

Another library, LCDWIKI_KBV.h, is loaded as well. This is a hardware-specific “helper” library that provides an interface to the actual hardware for the other libraries.

A look at the loop will show how this is done. TheLCDWIKI_GUI.hlibrary has a “Fill_Screen” method that fills the screen with an RGB color. You can specify the color in both hexadecimal or decimal format, the example illustrates both ways.

This sketch uses a number of functions from theLCDWIKI_GUI.hlibrary, along with some custom functions to draw geometric shapes. It then displays a cycle of graphs, shapes, and patterns on the LCD display.

One way in which this sketch differs is that most of the graphics routines are executed in the Setup function, so they only run once. The loop then displays some text with a selection of colors and fonts. The orientation is changed as it cycles through the loop.

This example makes use of a second file that contains fonts. The Display Scroll sketch illustrates a number of different methods of scrolling characters, in different fonts, colors and even languages.

One interesting thing about this test is that it illustrates how to display text in different “aspects”, Portrait and Landscape, Right side up and Reversed.

Unlike the previous examples that put the text in with a number of graphics, this example is a pretty simple one with just a block of text in different sizes and colors.  This makes it very simple to understand how the text is positioned on the display.

The result of running the sketch is the display screen fills with rows of hexadecimal values while the background alternates between blue and black and the orientation (or “aspect”) changes.  If you stand back to see the “big picture” you’ll note that the color values form “number patterns”.

The Display Phone Call sketch draws a mockup telephone keypad. Pressing one of the keys will display the result on a line of text at the top.  There is also a key to delete your entries, as well as ones to send and disconnect the call – the latter two are “dummy” functions of course as it’s only a demo.

In addition to the graphics and “helper” libraries that have been used in the previous examples this sketch also uses theTouchScreenlibrary to read screen interaction.  This was one of the libraries included in the original ZIP file.

As its name would imply, this sketch displays a bitmap image on the display. The images need to be placed onto the root of a microSD card, which in turn is plugged into the socket on the display shield.

The images will show off the display resolution, which is reasonably impressive. You’ll also note that to see them at their best, you need to be directly in front of the display, viewing the display at an angle causes the display to distort colors.

This example draws some small “switches” on the display. The switches are active and respond to touch.  There are slide switches, a push button, some radio buttons and some text-based expandable menus to test with.

The Calibration utility lets you calibrate the resistive touchscreen.  It achieves this by placing a number of crosses on the screen. You can calibrate the screen by using the stylus to touch the center of one of the crosses as accurately as you can.

After calibration, the sketch will display a number of calibration values for the resistive touchscreen. These values can be used in your future sketches to make the touchscreen more accurate.

The examples are a great way to demonstrate the capabilities of your touchscreen. But to really put your interface to work you’ll need to write your own interface code.

Writing a touchscreen interface can be challenging. I would suggest that you start by modifying one of the example codes, one that is closest to your desired interface.

The digital I/O connector at the back of the Mega is still accessible even when the touchscreen display shield is installed, so I used three of those connections for the LEDs. I hooked up each LED anode through a 220-ohm dropping resistor and connected them as follows:

The sketch is based upon the telephone keypad sketch. I modified it to eliminate the other functions and just display three buttons.  Then I added code to toggle the LEDs.

TheAdafruit GFX Libraryis a comprehensive graphics library that can be used in a variety of display applications.  It is a “core library”, meaning that it is called by other Adafruit libraries.

TheAdafruit TFTLCD Libraryis used. It uses the previous library to provide an easy method of drawing on the LCD display.  It works with LCD displays that use driver chips like the ILI9325 and ILI9328.

TheTouchScreenlibrary comes in the code that you downloaded from the LCD Wiki or from the CD ROM included with your touchscreen shield.  As its name implies it is used to interface with the touchscreen.

TheMCUFRIEND_kbvlibrary is also included in the software you obtained for your display shield. It takes care of supplying the correct hardware information for your display shield to the other libraries.

Next, we define some touchscreen parameters. You can ‘fine-tune” your code here by using parameters from your own display, which you can obtain from the Calibration Sketch we ran from the sample code.  Otherwise, just use the values here and you should be fine.

Next, we reset the display and try to identify it. This will run through a list of display chip drivers in the MCUFRIEND_kbv library and will attempt to select the correct one.

Now, still in the Setup, we set up the LCD display rotation and fill the background in black. Next step is to draw our buttons. Once we are done that the Setup is finished, and our screen should be displaying the three buttons on a black background.

We start by triggering the touchscreen, which is done by toggling pin 13 on the Arduino high. If something is touching the screen we read it and assign it to a TSPoint object named “p”.

We then need to reset the pin modes for two of the touchscreen pins back to outputs. This is done as these pins get shared with other LCD display functions and get set as inputs temporarily.

Touchscreen interfaces are used in a number of products, and now you can design your own devices using them. They can really make for an intuitive and advanced display and will give your project a very professional “look and feel” if done correctly.

This is not the only time we will look at touchscreen displays. Next time we’ll examine a capacitive touchscreen and we’ll explore the Adafruit Graphics libraries further to create some very fancy displays with controls and indicators.

Let"s learn how to use a touchscreen with the Arduino. We will examine the different types of touchscreens and will then create a simple interface using an inexpensive Arduino touchscreen shield.

Atmel ASF library has the driver for ili9325 controller, but I"m not sure if you"ll be able to use it with Mega series. At least you can run Atmel Studio, there are example projects for this lcd controller (for atmel boards with this controller) with the source code that you can use in your projects. You can review and edit it to implement your own code.

Displaying a custom image or graphic on a LCD display is a very useful task as displays are now a premium way of providing feedback to users on any project. With this functionality, we can build projects that display our own logo, or display images that help users better understand a particular task the project is performing, providing an all-round improved User Experience (UX) for your Arduino or ESP8266 based project. Today’s tutorial will focus on how you can display graphics on most Arduino compatible displays.

The procedure described in this tutorial works with all color displays supported by Adafruit’s GFX library and also works for displays supported by the TFTLCD library from Adafruit with little modification. Some of the displays on which this procedure works include:

While these are the displays we have, and on which this tutorial was tested, we are confident it will work perfectly fine with most of the other Arduino compatible displays.

For each of the displays mentioned above, we have covered in past how to program and connect them to Arduino. You should check those tutorials, as they will give you the necessary background knowledge on how each of these displays works.

For this tutorial, we will use the 2.8″ ILI9325 TFT Display which offers a resolution of 320 x 340 pixels and we will display a bitmap image of a car.

As usual, each of the components listed above can be bought from the links attached to them. While having all of the displays listed above may be useful, you can use just one of them for this tutorial.

To demonstrate how things work, we will use the 2.8″ TFT Display. The 2.8″ TFT display comes as a shield which plugs directly into the Arduino UNO as shown in the image below.

Not all Arduino displays are available as shields, so when working with any of them, connect the display as you would when displaying text (we recommend following the detailed tutorial for the display type you use of the above list). This means no special connection is required to display graphics.

Before an image is displayed on any of the Arduino screens, it needs to be converted to a C compatible hex file and that can only happen when the image is in bitmap form. Thus, our first task is to create a bitmap version of the graphics to be displayed or convert the existing image to a bitmap file. There are several tools that can be used for creation/conversion of bitmap images including, Corel Draw and Paint.net, but for this tutorial, we will use the Paint.net.

The resolution of the graphics created should be smaller than the resolution of your display to ensure the graphics fit properly on the display. For this example, the resolution of the display is 320 x 340, thus the resolution of the graphics was set to195 x 146 pixels.

Image2Code is an easy-to-use, small Java utility to convert images into a byte array that can be used as a bitmap on displays that are compatible with the Adafruit-GFX or Adafruit TFTLCD (with little modification) library.

With this done, we are now ready to write the code. Do note that this procedure is the same for all kind of displays and all kind of graphics. Convert the graphics to a bitmap file and use the Img2code utility to convert it into a hex file which can then be used in your Arduino code.

To reduce the amount of code, and stress involved in displaying the graphics, we will use two wonderful libraries; The GFX library and the TFTLCD library from Adafruit.

The GFX library, among several other useful functions, has a function called drawBitmap(), which enables the display of a monochrome bitmap image on the display. This function allows the upload of monochrome only (single color) graphics, but this can be overcome by changing the color of the bitmap using some code.

The Adafruit libraries do not support all of the displays but there are several modifications of the libraries on the internet for more displays. If you are unable to find a modified version of the library suitable for your the display, all you need do is copy the code of the drawBitmap() function from the GFX library and paste it in the Arduino sketch for your project such that it becomes a user-defined function.

The first two are thex and y coordinates of a point on the screen where we want the image to be displayed. The next argument is the array in which the bitmap is loaded in our code, in this case, it will be the name of the car and the text array located in the graphics.c file. The next two arguments are the width and height of the bitmap in pixels, in other words, the resolution of the image. The last argument is the color of the bitmap, we can use any color we like. The bitmap data must be located in program memory since Arduino has a limited amount of RAM memory available.

As usual, we start writing the sketch by including the libraries required. For this procedure, we will use the TFTLCD library alone, since we are assuming you are using a display that is not supported by the GFX library.

Next, we specify the name of the graphics to be displayed; car and title. At this stage, you should have added the bit array for these two bitmaps in the graphics.c file and the file should be placed in the same folder as the Arduino sketch.

With that done, we proceed to the void loop function, under the loop function, we call the drawbitmap() function to display the car and the text bitmap using different colors.

The last section of the code is the drawBitmap function itself, as earlier mentioned, to use the drawbitmap() function with the Adafruit TFTLCD library, we need to copy the function’s code and paste into the Arduino sketch.

Plug in your screen as shown above. If you are using any other display, connect it as shown in the corresponding linked tutorial. With the schematics in place, connect the Arduino board to your PC and upload the code. Don’t forget the graphics file needs to be in the same folder as the Arduino sketch.

That’s it for this tutorial guys. The procedure is the same for all kinds of Arduino compatible displays. If you get stuck while trying to replicate this using any other display, feel free to reach out to me via the comment sections below.

We’ve done quite a number of tutorials on the use of several displays with Arduino boards and today we will add another tutorial to that list. We will look at the ILI9325 based 2.8″ touchscreen display shown below and how it can be used with the Arduino to deliver a better user experience for your projects.

For today’s tutorial, we will use the ILI9325 driver based, 2.8″ display from Geekcreit. The display comes as a shield so it’s ready to be used for Arduino based projects. It is an 18-bit color display with a total of 262,000 different color shades. The display has a resolution of 240 x 320 pixels with individual pixel control.

Today’s project involves some very simple tasks which we will use to demonstrate the capabilities of the display. We will create a button which when touched, will trigger the Arduino to display a message on the screen. At the end of today’s tutorial, we would have gone through how to create a user interface on the touchscreen, how to detect when the screen is touched and how to display data on the screen.

The 2.8″ TFT display used for this project comes as a shield with the form factor of the Arduino Uno. This makes it easy to connect the shield to boards like the Uno, Mega and Due, as all we need to do, is plug it directly into the board, eliminating all the mess made by wires.  Plug the display to the Arduino as shown in the image below.

The fact that the display comes as a shield becomes a disadvantage when its used with the Arduino Uno as it occupies almost all the pins leaving just 2 digital pins and one analog pin for other uses. This can however, be overcome by using either the Arduino Mega or Due as they both work perfectly well with the display.

The code for this tutorial is heavily reliant on a modified version of Adafruit’s TFT LCD,GFX and touchscreen libraries. These libraries can be downloaded from the links attached to them.

As mentioned earlier, our focus for this tutorial will be to demonstrate, how UI can be created on the display and interpret touches to trigger actions. To achieve this, we will develop a simple sketch which displays a Youtube subscribe button. When the subscribe button is pressed, a text is displayed on the screen.

Calibration needs to be done before the touchscreen functionality of this display can be used. To calibrate the screen, we upload the code and Open the Serial Monitor to obtain the values of the display’s edges. Click (touch) on the top left corner of the display and write down the X and Y values displayed on the serial monitor. Then we edit the code to reflect those values. The X value goes to the TS_MAXX variable and the Y value goes to the TS_MAXY variable. Next, click on the bottom right corner of the display and enter the values displayed on the serial monitor for the TS_MINX and TS_MINY variables. With this done our display is now calibrated and ready for use.

Next, we declare the colors to be used with their hexadecimal values and we create an object of the Adafruit TFTLCD library, indicating the variables used to represent the pins of the Arduino to which the display is connected.

We start by initializing the serial monitor and the display. After this, we set the orientation of the LCD and fill the screen with a black color to serve as the background.

next, we draw a white frame on the display, set the text cursor to the desired location, change its color to white, and print the “Hello” text on the screen. By following the same procedure, we display the red YouTube text as well.

With the setup function all done, we move to the loop function, the algorithm in operation for the loop section is simple, each time the user clicks on the screen, we convert the point coordinates of the touch point into pixels using the Map function. After conversion, if that point is inside the red rectangle area, it means that the user has pressed the button, so we disable the button by setting this variable to false and we clear the screen so to display the “Thank you for Subscribing” message on the screen.

Copy the code above and create a new Arduino sketct. Ensure the libraries are installed and upload the code to the setup described under the schematics section. Once the upload is complete, you should see the display come up as shown below.

The LCD I am using is a 2.8″ TFT LCD with SPI communication. I also have another 16-bit Parallel TFT LCD but it will be another story for another time. For this post, let’s focus on how to display what you want on the 2.8″ LCD. You can find all details about this LCD from this page:http://www.lcdwiki.com/2.8inch_SPI_Module_ILI9341_SKU:MSP2807

First thing first, this LCD use SPI as the main communication protocol with your MCU. For STM32 users, HAL Library has already implemented this protocol which makes this project easier for us. But, a little knowledge about this protocol does not hurt anyone. SPI is short for Serial Peripheral Interface which, aside from two data lines, also has a clock line and select lines to choose between devices you want to communicate with.

This LCD uses ILI9341 as a single-chip SOC driver for a display with a resolution of 240×320. More details can be found in the official document of ILI9341. But the most important thing is that we have to establish astart sequencein order for this LCD to work. The “start sequence” includes many other sequences which are also defined in the datasheet. Each sequence starts when you send a command to ILI9341 and then some parameters to follow up. This sequence is applied for all communication between MCU and ILI9341.

For this project, I recommend using theSystem Workbench for STM32for coding and building the code. After installing and open the program, go to the source code you have just downloaded and double click the.cprojectfile. It will automatically be open in your IDE. Then build the program by right click on the folder you just open (TFTLCD) and chooseBuild Project. Wait for it to finish and upload it to the board by right clicking the folder, choose Run As and then clickAc6 STM32C/C++ Application. And that’s it for running the example.

The most important library for this project is obviously the ILI9341_Driver. This driver is built from the provided source code in the lcdwiki.com page. I only choose the part that we need to use the most in many applications like writing string, displaying image and drawing symbols. Another library from the wiki page is the TOUCH library. Most of the libraries I got from the Internet were not working properly due to some adjustments to the original one.

To draw symbols or even display images, we need a “byte array” of that image or symbol. As an illustration, to display an image from a game called Transistor, I have a “byte array” of that image stored in a file named transistor.h. You can find this file in the link below. Then, I draw each pixel from the image to the LCD by adding the code in the Display_Picture() function in the Display folder.void Display_Picture()

The above example is just only for displaying black and white image. In order to show a color image, we need to a little bit different. First, go tothis websiteto generate the array of the colour image. Remember to change your size to 320×240 and choose the 65K color option. Because it now takes up two bytes for one pixel, we need to send two bytes at once. You can check the Display_Color_Picture() function in the Display folder.void Display_Color_Picture()