adafruit tft lcd tutorial quotation

Hi there, I recently picked up an Adafruit 2.8"" TFT display for use with a Raspberry Pi 2. I installed the recommended Adafruit image, updated Raspbian, and everything seems to be working great, but have found the screen is so small, I can"t actually make use of the entire desktop. For instance, when I open a window, it cuts short, preventing me from accessing the lower options and commands. Most of the icons overlap, too. I"ve tried using the ctrl-left-click method to scan across the desktop, but that doesn"t seem to be working. I"ve also tried installing Kodi, but it doesn"t seem to want to load, either. Lastly, I tried changing the resolution settings through config.txt, but they haven"t seemed to have taken effect. Would I be right in saying that a fixed resolution may be hard-coded into the screen itself?

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.

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.

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.

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:

Displays are one of the best ways to provide feedback to users of a particular device or project and often the bigger the display, the better. For today’s tutorial, we will look on how to use the relatively big, low cost, ILI9481 based, 3.5″ Color TFT display with Arduino.

This 3.5″ color TFT display as mentioned above, is based on the ILI9481 TFT display driver. The module offers a resolution of 480×320 pixels and comes with an SD card slot through which an SD card loaded with graphics and UI can be attached to the display. The module is also pre-soldered with pins for easy mount (like a shield) on either of the Arduino Mega and Uno, which is nice since there are not many big TFT displays that work with the Arduino Uno.

One of the good things about this module is the ease with which it can be connected to either of the Arduino Mega or Uno. For this tutorial, we will use the Arduino Uno, since the module comes as a shield with pins soldered to match the Uno’s pinout. All we need to do is snap it onto the top of the Arduino Uno as shown in the image below, thus no wiring required.

To easily write code to use this display, we will use the GFX and TFT LCD libraries from “Adafruit” which can be downloaded here. With the library installed we can easily navigate through the examples that come with it and upload them to our setup to see the display in action. By studying these examples, one could easily learn how to use this display. However, I have compiled some of the most important functions for the display of text and graphics into an Arduino sketch for the sake of this tutorial. The complete sketch is attached in a zip file under the download section of this tutorial.

As usual, we will do a quick run through of the code and we start by including the libraries which we will use for the project, in this case, the Adafruit GFX and TFT LCD libraries.

With this done, the Void Setup() function is next. We start the function by issuing atft.reset() command to reset the LCD to default configurations. Next, we specify the type of the LCD we are using via the LCD.begin function and set the rotation of the TFT as desired. We proceed to fill the screen with different colors and display different kind of text using diverse color (via the tft.SetTextColor() function) and font size (via the tft.setTextSize() function).

The Adafruit library helps reduce the amount of work one needs to do while developing the code for this display, leaving the quality of the user interface to the limitations of the creativity and imagination of the person writing the code.

That’s it for this tutorial guys, thanks for reading. If you made some cool projects based on this or you just want to ask questions about this tutorial, feel free to reach out via the comment section below.

Displays are one of the best ways to provide feedback to users of a particular device or project and often the bigger the display, the better. For today’s tutorial, we will look on how to use the relatively big, low cost, ILI9481 based, 3.5″ Color TFT display with Arduino.

This 3.5″ color TFT display as mentioned above, is based on the ILI9481 TFT display driver. The module offers a resolution of 480×320 pixels and comes with an SD card slot through which an SD card loaded with graphics and UI can be attached to the display. The module is also pre-soldered with pins for easy mount (like a shield) on either of the Arduino Mega and Uno, which is nice since there are not many big TFT displays that work with the Arduino Uno.

One of the good things about this module is the ease with which it can be connected to either of the Arduino Mega or Uno. For this tutorial, we will use the Arduino Uno, since the module comes as a shield with pins soldered to match the Uno’s pinout. All we need to do is snap it onto the top of the Arduino Uno as shown in the image below, thus no wiring required.

To easily write code to use this display, we will use the GFX and TFT LCD libraries from “Adafruit” which can be downloaded here. With the library installed we can easily navigate through the examples that come with it and upload them to our setup to see the display in action. By studying these examples, one could easily learn how to use this display. However, I have compiled some of the most important functions for the display of text and graphics into an Arduino sketch for the sake of this tutorial. The complete sketch is attached in a zip file under the download section of this tutorial.

As usual, we will do a quick run through of the code and we start by including the libraries which we will use for the project, in this case, the Adafruit GFX and TFT LCD libraries.

With this done, the Void Setup() function is next. We start the function by issuing atft.reset() command to reset the LCD to default configurations. Next, we specify the type of the LCD we are using via the LCD.begin function and set the rotation of the TFT as desired. We proceed to fill the screen with different colors and display different kind of text using diverse color (via the tft.SetTextColor() function) and font size (via the tft.setTextSize() function).

The Adafruit library helps reduce the amount of work one needs to do while developing the code for this display, leaving the quality of the user interface to the limitations of the creativity and imagination of the person writing the code.

That’s it for this tutorial guys, thanks for reading. If you made some cool projects based on this or you just want to ask questions about this tutorial, feel free to reach out via the comment section below.

With four bright white LED backlight and 240 x 320 pixels with individual RGB pixel control, this colour 2.8in. TFT display features a resistive touchscreen for fingertip detection across the entire screen surface. The workload is lifted from the microcontroller by a built-in controller equipped with RAM buffering, and the display board has two modes: 8-bit and SPI.

It appears some TFT displays have the red and blue pixel elements swapped. This is rather odd because the default colour order is the same as the Adafruit libraries for that display.

Anyway, I have updated the master library driver files for the HX8357D display to permit the colour order to be defined in the setup file. By default the colour order is RGB (as in Adafruit libraries) but this can be changed to BGR. The Setup_15 header has been updated with the following two lines:

From TFT color displays to Adafruit display options, choose from the devices available here at Allied Electronics & Automation, part of RS Group. We stock high-quality products by leading manufacturers.

In order to explain what a thin-film-transistor - or TFT - display is, it"s worth explaining what TFT is. This is a field-effect transistor (FET) that is typically used in a liquid crystal display (LCD).

A TFT features a type of metal oxide semiconductor field-effect transistor (MOSFET) that"s made using large, thin films of active semiconductor layers. TFTs also feature a layer that acts as an electrical insulator and metal contacts. This is all layered over a substrate, which is typically glass.

The reason glass is the most commonly used substrate is that TFT is used in LCD displays and there is a TFT for each individual pixel. LCD technology sees liquid crystals manipulate light. The molecules in these crystals move as the temperature changes, and the temperature is changed using an electrical current.

While early LCD screens used a passive matrix of pixels, where each pixel was controlled by an electrical charge, this caused blurring of images on the screen. However, the introduction of TFT technology meant that the mix of pixels became active, thanks to the thin film transistors in the TFT, which are individually controlled.

Pixels in the active matrix used in a TFT LCD display are paired with a transistor that allows individual pixels to maintain charge without an electrical current being required whenever the pixel had to be changed.

As these TFT displays feature a TFT liquid crystal that includes a semiconductor switch for each pixel, each pixel can be directly controlled. This means that the TFT is acting as individual switches for each pixel.

As mentioned previously, early LCD displays were often blurry due to the need for an electrical charge for the pixels. TFT allows the images on the screen to sharpen up, becoming more defined. It also offers a high-quality color contrast and brightness setting.Better for the user

The higher-definition images are ideal for the user in terms of reducing eye strain. TFT technology also means that on a practical level, any fixes that are needed are easier to managed as pixels operate on an individual level.Less energy consumption

In comparison with LED screens, TFT displays have a longer half-life. They are also available in a range of sizes, which means that half-life can be extended again.Versatile

TFT displays are used in everyday applications, from computer work and TV watching, to corporate settings where larger screens are needed for meetings. They are also used in photography, featuring in cameras that require high definition, and navigation systems, mobile phones, and car dashboards.

At Allied Electronics & Automation, part of RS Group, we stock a range of TFT displays that are designed to provide you with the high-quality, high-definition screens you need. From Adafruit displays to interactive TFT LCD touchscreen displays, there are different options available to suit your needs.

We are a leading authorized distributor in North America and stock products by leading names including Lumex, Adafruit Industries, and we also have Focus Display Solutions and IEE displays available.

The Adafruit 2.8in. TFT LCD Touchscreen Display brings QVGA graphics to your next project using only 5 x SPI pins or 12 x GPIO pins if you can spare them. The screen is bright with a 4-LED backlight and can display 18-bits of colour (262,000 colours). There"s a display controller built in so your microcontroller doesn"t need to get involved in refreshing the screen, it just has to write the pixels once then it can move on to other tasks. SPI mode uses less pins but is slower while 8-bit mode uses more pins and is faster, the choice is up to you. Adafruit have software and tutorials to support you whichever mode you decide to use, see the links below. The board also has a micro-SD card socket that you can use to store files and images.

Visit https://learn.adafruit.com where Adafruit provide a free tutorial for the Raspberry Pi, and another tutorial for the Arduino. They also have an open source library to drive the display in 8-bit mode, and another to use SPI mode. Please note that while the screen is capable of 18-bit colour, the Adafruit code uses 16-bits for efficiency. It"s highly unlikely that you"ll ever notice any difference.