rotate view of tft display arduino in stock
I am a total newbie. I have the Adafruit 2.2" 240x320 TFT LCD using the ILI9340 graphictest sketch and I am able to display the tiger.bmp image fine from the SD card. However, I can"t figure out how to rotate from the current portrait to landscape.
----> 2.2 18-bit color TFT LCD display with microSD card breakout [EYESPI Connector] : ID 1480 : $24.95 : Adafruit Industries, Unique & fun DIY electronics and kits
I have a “square” rotating on my 3.5 Inch TFT screen (ILI9486 driver) with dots/circles at each of its 4 corners. It is connected to an Arduino MEGA 2560 There are a few issues with how it is currently implemented that I would like guidance on:
This code/project is just to familiarise myself with the lower-level theory of rotating images on a screen. I am following 3Blue1Brown’s linear algebra series and became interested in using matrices as transformations. I will eventually work up to the 3D case, but I’d prefer to get the 2D technical issues out of the way first.
As I stated in the problem summary, the square is “flashing”. See below for a video. The flashing is caused by how I clear and display the square. The process is essentially:
My second major issue is that the square is not “closed”. It"s not apparent in the images above because they had a smaller angle of rotation. This image shows what I’m talking about:
I’ve labelled the vertices 1 – 4 in the picture. I know that the issue is caused by how I’m updating the square – the line connecting vertices 1 and 4 is only valid for a very short time interval – it is drawn just after vertex 4 is drawn, after which the position of 1 is immediately updated, so the line is pointing to the old position of vertex 1 for the majority of the time. I’ve tried altering the order in which lines are drawn but this only shifts the problem to different vertices.
In this article, you will learn how to use TFT LCDs by Arduino boards. From basic commands to professional designs and technics are all explained here.
In electronic’s projects, creating an interface between user and system is very important. This interface could be created by displaying useful data, a menu, and ease of access. A beautiful design is also very important.
There are several components to achieve this. LEDs, 7-segments, Character and Graphic displays, and full-color TFT LCDs. The right component for your projects depends on the amount of data to be displayed, type of user interaction, and processor capacity.
TFT LCD is a variant of a liquid-crystal display (LCD) that uses thin-film-transistor (TFT) technology to improve image qualities such as addressability and contrast. A TFT LCD is an active matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven LCDs with a few segments.
In Arduino-based projects, the processor frequency is low. So it is not possible to display complex, high definition images and high-speed motions. Therefore, full-color TFT LCDs can only be used to display simple data and commands.
In this article, we have used libraries and advanced technics to display data, charts, menu, etc. with a professional design. This can move your project presentation to a higher level.
In electronic’s projects, creating an interface between user and system is very important. This interface could be created by displaying useful data, a menu, and ease of access. A beautiful design is also very important.
There are several components to achieve this. LEDs, 7-segments, Character and Graphic displays, and full-color TFT LCDs. The right component for your projects depends on the amount of data to be displayed, type of user interaction, and processor capacity.
TFT LCD is a variant of a liquid-crystal display (LCD) that uses thin-film-transistor (TFT) technology to improve image qualities such as addressability and contrast. A TFT LCD is an active matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven LCDs with a few segments.
In Arduino-based projects, the processor frequency is low. So it is not possible to display complex, high definition images and high-speed motions. Therefore, full-color TFT LCDs can only be used to display simple data and commands.
In this article, we have used libraries and advanced technics to display data, charts, menu, etc. with a professional design. This can move your project presentation to a higher level.
Size of displays affects your project parameters. Bigger Display is not always better. if you want to display high-resolution images and signs, you should choose a big size display with higher resolution. But it decreases the speed of your processing, needs more space and also needs more current to run.
After choosing the right display, It’s time to choose the right controller. If you want to display characters, tests, numbers and static images and the speed of display is not important, the Atmega328 Arduino boards (such as Arduino UNO) are a proper choice. If the size of your code is big, The UNO board may not be enough. You can use Arduino Mega2560 instead. And if you want to show high resolution images and motions with high speed, you should use the ARM core Arduino boards such as Arduino DUE.
In electronics/computer hardware a display driver is usually a semiconductor integrated circuit (but may alternatively comprise a state machine made of discrete logic and other components) which provides an interface function between a microprocessor, microcontroller, ASIC or general-purpose peripheral interface and a particular type of display device, e.g. LCD, LED, OLED, ePaper, CRT, Vacuum fluorescent or Nixie.
The display driver will typically accept commands and data using an industry-standard general-purpose serial or parallel interface, such as TTL, CMOS, RS232, SPI, I2C, etc. and generate signals with suitable voltage, current, timing and demultiplexing to make the display show the desired text or image.
The LCDs manufacturers use different drivers in their products. Some of them are more popular and some of them are very unknown. To run your display easily, you should use Arduino LCDs libraries and add them to your code. Otherwise running the display may be very difficult. There are many free libraries you can find on the internet but the important point about the libraries is their compatibility with the LCD’s driver. The driver of your LCD must be known by your library. In this article, we use the Adafruit GFX library and MCUFRIEND KBV library and example codes. You can download them from the following links.
You must add the library and then upload the code. If it is the first time you run an Arduino board, don’t worry. Just follow these steps:Go to www.arduino.cc/en/Main/Software and download the software of your OS. Install the IDE software as instructed.
By these two functions, You can find out the resolution of the display. Just add them to the code and put the outputs in a uint16_t variable. Then read it from the Serial port by Serial.println(); . First add Serial.begin(9600); in setup().
First you should convert your image to hex code. Download the software from the following link. if you don’t want to change the settings of the software, you must invert the color of the image and make the image horizontally mirrored and rotate it 90 degrees counterclockwise. Now add it to the software and convert it. Open the exported file and copy the hex code to Arduino IDE. x and y are locations of the image. sx and sy are sizes of image. you can change the color of the image in the last input.
Upload your image and download the converted file that the UTFT libraries can process. Now copy the hex code to Arduino IDE. x and y are locations of the image. sx and sy are size of the image.
In this template, We converted a .jpg image to .c file and added to the code, wrote a string and used the fade code to display. Then we used scroll code to move the screen left. Download the .h file and add it to the folder of the Arduino sketch.
In this template, We used sin(); and cos(); functions to draw Arcs with our desired thickness and displayed number by text printing function. Then we converted an image to hex code and added them to the code and displayed the image by bitmap function. Then we used draw lines function to change the style of the image. Download the .h file and add it to the folder of the Arduino sketch.
In this template, We created a function which accepts numbers as input and displays them as a pie chart. We just use draw arc and filled circle functions.
In this template, We added a converted image to code and then used two black and white arcs to create the pointer of volumes. Download the .h file and add it to the folder of the Arduino sketch.
In this template, We added a converted image and use the arc and print function to create this gauge. Download the .h file and add it to folder of the Arduino sketch.
while (a < b) { Serial.println(a); j = 80 * (sin(PI * a / 2000)); i = 80 * (cos(PI * a / 2000)); j2 = 50 * (sin(PI * a / 2000)); i2 = 50 * (cos(PI * a / 2000)); tft.drawLine(i2 + 235, j2 + 169, i + 235, j + 169, tft.color565(0, 255, 255)); tft.fillRect(200, 153, 75, 33, 0x0000); tft.setTextSize(3); tft.setTextColor(0xffff); if ((a/20)>99)
while (b < a) { j = 80 * (sin(PI * a / 2000)); i = 80 * (cos(PI * a / 2000)); j2 = 50 * (sin(PI * a / 2000)); i2 = 50 * (cos(PI * a / 2000)); tft.drawLine(i2 + 235, j2 + 169, i + 235, j + 169, tft.color565(0, 0, 0)); tft.fillRect(200, 153, 75, 33, 0x0000); tft.setTextSize(3); tft.setTextColor(0xffff); if ((a/20)>99)
In this template, We display simple images one after each other very fast by bitmap function. So you can make your animation by this trick. Download the .h file and add it to folder of the Arduino sketch.
In this template, We just display some images by RGBbitmap and bitmap functions. Just make a code for touchscreen and use this template. Download the .h file and add it to folder of the Arduino sketch.
The speed of playing all the GIF files are edited and we made them faster or slower for better understanding. The speed of motions depends on the speed of your processor or type of code or size and thickness of elements in the code.
By these two functions, You can find out the resolution of the display. Just add them to the code and put the outputs in a uint16_t variable. Then read it from the Serial port by Serial.println();. First add Serial.begin(9600); in setup().
The 1.8inch LCD uses the PH2.0 8PIN interface, which can be connected to the Raspberry Pi according to the above table: (Please connect according to the pin definition table. The color of the wiring in the picture is for reference only, and the actual color shall prevail.)
The example we provide is based on STM32F103RBT6, and the connection method provided is also the corresponding pin of STM32F103RBT6. If you need to transplant the program, please connect according to the actual pin.
ST7735S is a 132*162 pixel LCD, and this product is a 128*160 pixel LCD, so some processing has been done on the display: the display starts from the second pixel in the horizontal direction, and the first pixel in the vertical direction. Start to display, so as to ensure that the position corresponding to the RAM in the LCD is consistent with the actual position when displayed.
Note: Different from the traditional SPI protocol, the data line from the slave to the master is hidden since the device only has display requirement.
CPOL determines the level of the serial synchronous clock at idle state. When CPOL = 0, the level is Low. However, CPOL has little effect to the transmission.
CPHA determines whether data is collected at the first clock edge or at the second clock edge of serial synchronous clock; when CPHL = 0, data is collected at the first clock edge.
PS: If you are using the system of the Bullseye branch, you need to change "apt-get" to "apt", the system of the Bullseye branch only supports Python3.
Framebuffer uses a video output device to drive a video display device from a memory buffer containing complete frame data. Simply put, a memory area is used to store the display content, and the display content can be changed by changing the data in the memory.
There is an open source project on github: fbcp-ili9341. Compared with other fbcp projects, this project uses partial refresh and DMA to achieve a speed of up to 60fps
If you need to draw pictures, or display Chinese and English characters, we provide some basic functions here about some graphics processing in the directory RaspberryPi\c\lib\GUI\GUI_Paint.c(.h).
Select image buffer: The purpose of the selection is that you can create multiple image attributes, there can be multiple images buffer, you can select each image you create.
Set points of the display position and color in the buffer: here is the core GUI function, processing points display position and color in the buffer.
The fill color of a certain window in the image buffer: the image buffer part of the window filled with a certain color, usually used to fresh the screen into blank, often used for time display, fresh the last second of the screen.
Draw rectangle: In the image buffer, draw a rectangle from (Xstart, Ystart) to (Xend, Yend), you can choose the color, the width of the line, whether to fill the inside of the rectangle.
Draw circle: In the image buffer, draw a circle of Radius with (X_Center Y_Center) as the center. You can choose the color, the width of the line, and whether to fill the inside of the circle.
Write English string: In the image buffer, use (Xstart Ystart) as the left vertex, write a string of English characters, you can choose Ascii visual character library, font foreground color, font background color.
Write Chinese string: in the image buffer, use (Xstart Ystart) as the left vertex, write a string of Chinese characters, you can choose character font, font foreground color, font background color of the GB2312 encoding
Write numbers: In the image buffer,use (Xstart Ystart) as the left vertex, write a string of numbers, you can choose Ascii visual character library, font foreground color, font background color.
Display time: in the image buffer,use (Xstart Ystart) as the left vertex, display time,you can choose Ascii visual character font, font foreground color, font background color.;
Python has an image library PIL official library link, it do not need to write code from the logical layer like C, can directly call to the image library for image processing. The following will take 1.54inch LCD as an example, we provide a brief description for the demo.
The first parameter defines the color depth of the image, which is defined as "1" to indicate the bitmap of one-bit depth. The second parameter is a tuple that defines the width and height of the image. The third parameter defines the default color of the buffer, which is defined as "WHITE".
The first argument is a tuple of four elements. (20,10) is the coordinate value in the upper left corner of the rectangle, and (70,60) is the coordinate value in the lower right corner of the rectangle. Fill =" WHITE" means BLACK inside, and outline="BLACK" means the color of the outline is black.
Draw an inscribed circle in the square, the first parameter is a tuple of 4 elements, with (150, 15) as the upper left corner vertex of the square, (190, 55) as the lower right corner vertex of the square, specifying the level median line of the rectangular frame is the angle of 0 degrees, the second parameter indicates the starting angle, the third parameter indicates the ending angle, and fill = 0 indicates that the the color of the line is white.
The first parameter is the coordination of the enclosing rectangle. The second and third parameters are the beginning and end degrees of the circle. The fourth parameter is the fill color of the circle.
Note: Each character library contains different characters; If some characters cannot be displayed, it is recommended that you can refer to the encoding set ro used.
The first parameter is a tuple of 2 elements, with (40, 50) as the left vertex, the font is Font2, and the fill is the font color. You can directly make fill = "WHITE", because the regular color value is already defined Well, of course, you can also use fill = (128,255,128), the parentheses correspond to the values of the three RGB colors so that you can precisely control the color you want. The second sentence shows Micro Snow Electronics, using Font3, the font color is white.
Open main.c, you can see all the test programs, remove the comments in front of the test programs on the corresponding screen, and recompile and download.
For the screen, if you need to draw pictures, display Chinese and English characters, display pictures, etc., you can use the upper application to do, and we provide some basic functions here about some graphics processing in the directory STM32\STM32F103RB\User\GUI_DEV\GUI_Paint.c(.h)
Select image buffer:the purpose of the selection is that you can create multiple image attributes, image buffer can exist multiple, you can select each image you create.
Image buffer part of the window filling color: the image buffer part of the window filled with a certain color, generally as a window whitewashing function, often used for time display, whitewashing on a second
Draw rectangle: In the image buffer, draw a rectangle from (Xstart, Ystart) to (Xend, Yend), you can choose the color, the width of the line, whether to fill the inside of the rectangle.
Draw circle: In the image buffer, draw a circle of Radius with (X_Center Y_Center) as the center. You can choose the color, the width of the line, and whether to fill the inside of the circle.
Write English string: In the image buffer, use (Xstart Ystart) as the left vertex, write a string of English characters, can choose Ascii visual character library, font foreground color, font background color.
Write Chinese string: in the image buffer, use (Xstart Ystart) as the left vertex, write a string of Chinese characters, you can choose GB2312 encoding character font, font foreground color, font background color.
Write numbers: In the image buffer,use (Xstart Ystart) as the left vertex, write a string of numbers, you can choose Ascii visual character library, font foreground color, font background color.
Display time: in the image buffer,use (Xstart Ystart) as the left vertex, display time,you can choose Ascii visual character font, font foreground color, font background color.
For the screen, if you need to draw pictures, display Chinese and English characters, display pictures, etc., you can use the upper application to do, and we provide some basic functions here about some graphics processing in the directory GUI_Paint.c(.h)
Select image buffer:the purpose of the selection is that you can create multiple image attributes, image buffer can exist multiple, you can select each image you create.
Draw rectangle: In the image buffer, draw a rectangle from (Xstart, Ystart) to (Xend, Yend), you can choose the color, the width of the line, whether to fill the inside of the rectangle.
Draw circle: In the image buffer, draw a circle of Radius with (X_Center Y_Center) as the center. You can choose the color, the width of the line, and whether to fill the inside of the circle.
Write English string: In the image buffer, use (Xstart Ystart) as the left vertex, write a string of English characters, can choose Ascii visual character library, font foreground color, font background color.
Write Chinese string: in the image buffer, use (Xstart Ystart) as the left vertex, write a string of Chinese characters, you can choose GB2312 encoding character font, font foreground color, font background color.
Write numbers: In the image buffer,use (Xstart Ystart) as the left vertex, write a string of numbers, you can choose Ascii visual character library, font foreground color, font background color.
Write numbers with decimals: at (Xstart Ystart) as the left vertex, write a string of numbers with decimals, you can choose Ascii code visual character font, font foreground color, font background color
Display time: in the image buffer,use (Xstart Ystart) as the left vertex, display time,you can choose Ascii visual character font, font foreground color, font background color.
The four sample codes: DisplayString, DrawGraphic, ShowBMP, and TouchPanel are used to display strings, graphics, pictures in BMP format, and touch pen functions.
Before performing the ShowImage display picture experiment, first, copy the pictures in the PIC folder in the data to the root directory of the SD card
Before experimenting with the TouchPanel, the touchscreen must be calibrated according to the displayed prompts. Open the corresponding project, burn the program, and you will be prompted when running:
This demo has been tested on XNUCLEO-F103RB, just insert XNUCLEO-F103RB directly as shown below. The model of XNUCLEO-F103RB is STM32F103RBT6. If you need to transplant the program, please connect it according to the actual pin and the schematic diagram
The demos are developed based on the HAL library. Download the program, find the STM32 program file directory, and open the STM32 with four project folders: DisplayString, DrawGraphic, ShowImage, and Touchscreen.
The four sample codes: DisplayString, DrawGraphic, ShowBMP, and TouchPanel are used to display strings, graphics, pictures in BMP format, and touch pen functions.
Before performing the ShowImage display picture experiment, first, copy the pictures in the PIC folder in the data to the root directory of the SD card
Before experimenting with the TouchPanel, the touchscreen must be calibrated according to the displayed prompts. Open the corresponding project, burn the program, and you will be prompted when running:
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:
Note: some people find issues with this display when trying to read from the SD card. We don’t know why that happens. In fact, we tested a couple of times and it worked well, and then, when we were about to record to show you the final result, the display didn’t recognized the SD card anymore – we’re not sure if it’s a problem with the SD card holder that doesn’t establish a proper connection with the SD card. However, we are sure these instructions work, because we’ve tested them.
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 the previous article, I described the steps needed to install an LCD touchscreen on the Raspberry Pi. In this article, I will show you how to adjust the screen rotation of the LCD to landscape mode, and will show you how to calibrate the touchscreen pointer for optimal accuracy. Just follow the steps below to compete the process of setting up your Raspberry Pi LCD touchscreen:
1. First we need to change the setting for screen rotation in the /boot/cmdline.txt file. This setting is called fbtft_device.rotate=X. By default, this is set to X=0, which results in a portrait mode screen orientation. In order to switch the orientation to landscape mode, change fbtft_device.rotate=0 to fbtft_device.rotate=90. Enter sudo nano /boot/cmdline.txt at the command prompt. There should only be one line in this file. Go to the end of it and you will find the fbtft_device.rotate=X setting. Change the value from 0 to 90:
However, if you try to touch the screen now, you will find that the pointer movement does not correspond to your finger movement. This is because the LCD screen driver and the touchscreen controller driver have separate settings for screen rotation. We need to change the rotation of the touchscreen controller driver to match the rotation of the LCD screen driver.
2. You probably noticed that dragging your finger to the right moves the pointer up, not to the right. This indicates that the x and y axes of the touchscreen are swapped. To correct this, we need to swap the x axis for the y axis. This can be done by changing the swap_xy=X parameter in /etc/modules.
Now if you drag your finger around the screen, you will notice that the y axis (up and down) is correctly aligned with the motion of your finger. However, the x axis (left and right) is still inverted. To fix this, we need to install two more kernel modules, xinput and evtest. xinput is a Linux utility that will allow us to configure input device settings for the touchscreen controller, and evtest is an input device event monitor and query tool.
You can rotate the screen 90 degrees (as we did in this tutorial) and the power connector will be at the bottom of the screen, but you can also rotate it 270 degrees so that the power connector is at the top of the screen. To do this, simply enter fbtft_device.rotate=270 in the /boot/cmdline.txt file. Then change the DISPLAY=:0 xinput --set-prop "ADS7846 Touchscreen" "Evdev Axis Inversion" 0 1 line in the /etc/X11/xinit/xinitrc file to DISPLAY=:0 xinput --set-prop "ADS7846 Touchscreen" "Evdev Axis Inversion" 1 0. All you need to do is switch the values of the 0 and 1 at the end of this line.
Now that we have our LCD touchscreen up and running, the final step in the installation is the calibration of touch control. This will make the pointer much more accurate and easier to use.
3. The calibration tool we will use is called ts_calibrate. We will also be using a program to check the results of the calibration called ts_test. In order to use ts_calibrate and ts_test, we must first set proper environmental variables. Enter export TSLIB_TSDEVICE=/dev/input/event0 into the command prompt, then enter export TSLIB_FBDEVICE=/dev/fb1:
4. Now we can use ts_calibrate. Enter ts_calibrate at the command prompt (make sure you are still in root mode) to run the ts_calibrate program. The program will consecutively display five crosses on different parts of the screen, which you need to touch with as much precision as possible:
This calibration data will be written to a calibration file called /etc/pointercal. To view the contents of this file, enter cat /etc/pointercal at the root command prompt.
Drag the cross around the screen and observe how closely it follows your finger or stylus to test the accuracy of the calibration. Now press the “Draw” button to enter the drawing mode:
This is kind of a long process, but it is well worth it if you want to get the LCD touchscreen set up properly. So if you have any trouble setting this up or have anything to say, please leave a comment below. Also, if you found this article useful, please share it with your friends!
This is a 3.5” IPS capacitive Touchscreen Display. The module, with a resolution of 480x320, adopts ILI9488 as driver IC and SPI (4-line) communication mode. The board integrates touch chip GT911, employing I2C communication to realize multiple touchpoints controlling. The module also integrates an SD card slot allowing you to easily read the full-color bitmap. There are two modes of wiring supplied, normal pin header wiring and GDI. The latter one requires to work with a main controller board with a GDI interface (e.g. FireBeetle-M0). You can use it with only one FPC line plugging in, which reduces the complexity of the wiring. Furthermore, it features high resolution, wide viewing angle, and simple wiring, which can be used in all sorts of display applications, such as, IoT controlling device, game console, desktop event notifier, touch interface, etc.
The product is a Breakout module. It adopts SPI communication and has onboard GDI interface, which reduces the complexity of wiring and can easily display the contents read from SD card.
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.
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.
As the code is a bit longer and for better understanding I will post the source code of the program in sections with description for each section. And at the end of this article I will post the complete source 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.
Next is the distance sensor button. First we need to set the color and then using the fillRoundRect() function we will draw the rounded rectangle. Then we will set the color back to white and using the drawRoundRect() function we will draw another rounded rectangle on top of the previous one, but this one will be without a fill so the overall appearance of the button looks like it has a frame. On top of the button we will print the text using the big font and the same background color as the fill of the button. The same procedure goes for the two other buttons.
drawDistanceSensor(); // It is called only once, because in the next iteration of the loop, this above if statement will be false so this funtion won"t be called. This function will draw the graphics of the first example.
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.
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:
drawDistanceSensor(); // It is called only once, because in the next iteration of the loop, this above if statement will be false so this funtion won"t be called. This function will draw the graphics of the first example.