lcd display not working arduino made in china
Bookmark the Vilros Raspberry Pi and Arduino Downloads page for future reference. Here you will find PDF versions of Quick Start Guides, Example Arduino Code, and even our downloadable version of NOOBS and RetroPie.
Read the past posts. I hooked up wrong to the backlite, and the pot worked to dim the backlight. I hooked up as it should have been, and the LCD contrast does not work.
That"s good summary. I still don"t recommend using 10K pot for backlight though but I get how overconfident you are so do what you want. So now you can"t make the contrast to change. Please disconnect all data, RS, EN wires from the LCD if you want to try the contrast. I didn"t get whether you are running some LCD code or not. Just don"t run LCD code and get the contrast step to work first. Bear in mind, you did connect up wrong wires so the LCD may have already been damaged beyond operation. Things happen rather quickly when wires are connected up wrong. Again, where are those pictures? You apparently were overconfident and under-organized but a few pictures will redeem yourself here. You were "connecting everything correctly" and that made several helpers think hard what other things could have gone wrong, all wasting their time, only if you showed a pic or two.
i have tested with 2 computers (win10, win7 and linux) with the last arduino ide versions (store and web download for windows), with arduino web ide, i always have the same issue and the same reactions on the board
I have updated the drivers, the code is compiled and executed proprely but i can not send any commands (and maybe other features are disactivated, but i didn"t find them yet)
This stems from the fact that the LCD controller itself does not inherently support the function and in fact treats the ASCII codes for and as displayable characters instead of control codes.
The fact that the LiquidCrystal library inherits from Print class and thus permits the use of println() essentially makes things worse. Instead of barfing and spitting out an error message it just happily displays two unrelated characters on the screen and the uninitiated have no idea of the cause.
In my opinion the basic LiquidCrystal library should concentrate on implementing all of the capabilities of the LCD controller and no more. If people want a library that more closely emulates a CRT (or LCD) terminal that is fine, but I think it should be done in a different library.
@Railroader Thanks for your advice, although I felt that it was a little patronising. But I guess that since the Arduino is primarily targeted at schoolchildren and for educational purposes, that"s a fair enough assumption of my age and career.
I am aware that there are better alternatives for screens that can be found for under £15. I was curious what was in a £15 quid projector and bought it for that reason. Disassembling it was fun and has already netted me lenses, heatsinks, and LEDs etc. for other projects which is worth more than its cost. The reason I asked was because a) I am loathe to bin the LCD and hence contribute to our electronic waste problems, and b) I am specifically looking for LEDs (most of the displays on eBay and Amazon are OLEDs) as I want to make an ESP32-controlled projector as a project. Non-OLEDs are difficult to find on eBay/Amazon nowadays. Hence I was asking on the off-chance that this screen might be similar to something else in Occidental part of the world that I could use.
From what you say it feels its very unlikely for there to be a shortcut and I"ll have decode the signals manually. Designing and manufacturing (or finding a 30 pin adapter) is not a problem but I can"t justify to myself spending the better part of my weekends in a month to decode the signals just to use it when I can spend £10 buying an SPI LCD from eBay which does the exact same thing. I"ll probably bite the bullet and do that.
Shame about having to bin the screen though. I have found the schematics for the GM8284DD chip and probably with a magnifying glass would be able to make out the LCD connections (RGB input etc.) on the circuit board but again, I"m not sure if its that cost-efficient spending that many weekends working on it...
i bought a bunch of LCDs with I2C from china and i used some of them and they work great. after a month of the purchase, i opened one of the NEW LCD displays and only exchanged the wires with a perfectly working one (to make sure there is no code or wire errors) but its not working.
I have a project where I"ll have to interface 5-6 sensors with arduino via LCD and wireless module as well. I"m trying to interface LCD for now without any sensors.
I switched to using an I2C Port Expander Module , still I"m not getting any viable results. All I get is one row of boxes followed by an empty one then another row of boxes followed by another empty row.
Learn how to wire the 20x4 LCD to Arduino Uno in a few simple steps. The primary components for this circuit are: Arduino Uno - R3 and 20x4 LCD. Drag and drop these components onto the canvas, and instantly get a list of secondary parts, wiring...
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 next example is controlling an RGB LED using these three RGB sliders. For example if we start to slide the blue slider, the LED will light up in blue and increase the light as we would go to the maximum value. So the sliders can move from 0 to 255 and with their combination we can set any color to the RGB LED, but just keep in mind that the LED cannot represent the colors that much accurate.
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.
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.
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 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 next example is controlling an RGB LED using these three RGB sliders. For example if we start to slide the blue slider, the LED will light up in blue and increase the light as we would go to the maximum value. So the sliders can move from 0 to 255 and with their combination we can set any color to the RGB LED, but just keep in mind that the LED cannot represent the colors that much accurate.
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.
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.
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 post we are going to solve Arduino software and driver related issues which are driving some beginners crazy and we will also address some of the problems related to Arduino hardware.
You landed on this page because you could not upload your sketch to Arduino or it is not even detected by your trusty computer. Here we will discuss the possible problems why your Arduino board is not detected or why you couldn’t upload the sketch/code and we will see the recommended solutions.
This is a very common issue faced by most Arduino beginners and sometimes even who has intermediate experience with Arduino. Your IDE will not show the connected Arduino board and you device manager will say “unknown USB device”, when you try to fix with windows tools you will still end up not fixing the issue.
A USB to serial converter module is utilized on all Arduino boards to uploading sketches to the microcontroller and also for serial communication between the computer and the main microcontroller.
Here is an Arduino UNO clone with ATmega16U2 controller which is used as USB to serial converter, the same converter is also utilized on genuine Arduino boards.
The above Arduino board is SMD type; this board has exactly same specification as genuine Arduino UNO. As you can see there is a difference in the USB to serial converter chip. This is called CH340G USB to serial converter chip.
You can see this on cheap Chinese Arduino clones; this chip will not be detected neither by your computer nor the IDE. You have to install CH340G driver to your computer only then your computer will recognize the device and able to upload sketches.
Most beginners make this mistake, they select wrong COM port. Each computer has different COM port numbers and you have to select the right one for your PC. If your Arduino board sport ATmega16U2 chip it will show you to which COM port number your board is connected to and select that one.
Whenever you are uploading a code to your Arduino board, make sure that Tx and Rx pins are not connected anywhere else in the circuit. Once you finish uploading the code, you may reconnect the Tx and Rx pins to your circuit. The Tx and Rx (pin number 0 and 1) are the pins where the code gets uploaded to the microcontroller.
A defective USB cable can make your Arduino board undetectable on your computer, not even detectable on your device manager and also may cause frequent disconnection from your PC. If you find yourself in this circumstance, please replace the USB cable that connects to your computer and Arduino board.
A dusty / rusted USB port on your computer may cause frequent disconnections or may prevent uploading of the code altogether, this could be because the rusted USB lines may not establish proper physical contact with the USB cable.
Always connect your Arduino board to a good USB port of your computer and make sure that USB port on the Arduino board also has no physical defects. If problems arise from a particular USB port, don’t use that again.
There could be problems with microcontroller IC or with other components which are not visually inspect-able / visible or replaceable, in such case replacing the whole board is the only solution.
Download a fresh copy of IDE from the official website of Arduino and install it to your computer. Re-installing the latest / same version of Arduino IDE may solve some installation issues with your computer.
There could be situations where the newer IDE didn’t work well with your Arduino board, if so please try roll backing to the previous version which you have been using before.
This is the final troubleshooting step if you can’t get your Arduino board to work. Connect your board to another computer (with proper drivers) which is known for uploading Arduino sketches without any issues. If the issue still persist, your board has some problem and please replace your board.
As a 2inch IPS display module with a resolution of 240 * 320, it uses an SPI interface for communication. The LCD has an internal controller with basic functions, which can be used to draw points, lines, circles, and rectangles, and display English, Chinese as well as pictures.
The 2inch 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 LCD supports 12-bit, 16-bit, and 18-bit input color formats per pixel, namely RGB444, RGB565, and RGB666 three color formats, this demo uses RGB565 color format, which is also a commonly used RGB format.
For most LCD controllers, the communication mode of the controller can be configured, usually with an 8080 parallel interface, three-wire SPI, four-wire SPI, and other communication methods. This LCD uses a four-wire SPI communication interface, which can greatly save the GPIO port, and the communication speed will be faster.
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.
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.
Note: The script will replace the corresponding /boot/config.txt and /etc/rc.local and restart, if the user needs, please back up the relevant files in advance.
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).
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.
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.;
2. The module_init() function is automatically called in the INIT () initializer on the LCD, but the module_exit() function needs to be called by itself
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.
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.
Arduino (open-source hardware and software company, project, and user community that designs and manufactures single-board microcontrollers and microcontroller kits for building digital devices. Its hardware products are licensed under a CC BY-SA license, while software is licensed under the GNU Lesser General Public License (LGPL) or the GNU General Public License (GPL),manufacture of Arduino boards and software distribution by anyone. Arduino boards are available commercially from the official website or through authorized distributors.
Arduino board designs use a variety of microprocessors and controllers. The boards are equipped with sets of digital and analog input/output (I/O) pins that may be interfaced to various expansion boards ("shields") or breadboards (for prototyping) and other circuits. The boards feature serial communications interfaces, including Universal Serial Bus (USB) on some models, which are also used for loading programs. The microcontrollers can be programmed using the C and C++ programming languages, using a standard API which is also known as the Arduino Programming Language, inspired by the Processing language and used with a modified version of the Processing IDE. In addition to using traditional compiler toolchains, the Arduino project provides an integrated development environment (IDE) and a command line tool developed in Go.
The Arduino project began in 2005 as a tool for students at the Interaction Design Institute Ivrea, Italy,sensors and actuators. Common examples of such devices intended for beginner hobbyists include simple robots, thermostats and motion detectors.
The name Arduino comes from a bar in Ivrea, Italy, where some of the founders of the project used to meet. The bar was named after Arduin of Ivrea, who was the margrave of the March of Ivrea and King of Italy from 1002 to 1014.
The Arduino project was started at the Interaction Design Institute Ivrea (IDII) in Ivrea, Italy.BASIC Stamp microcontroller at a cost of $50. In 2003 Hernando Barragán created the development platform Casey Reas. Casey Reas is known for co-creating, with Ben Fry, the Processing development platform. The project goal was to create simple, low cost tools for creating digital projects by non-engineers. The Wiring platform consisted of a printed circuit board (PCB) with an ATmega128 microcontroller, an IDE based on Processing and library functions to easily program the microcontroller.Arduino.
Following the completion of the platform, lighter and less expensive versions were distributed in the open-source community. It was estimated in mid-2011 that over 300,000 official Arduinos had been commercially produced,
At the end of 2008, Gianluca Martino"s company, Smart Projects, registered the Arduino trademark in Italy and kept this a secret from the other co-founders for about two years. This was revealed when the Arduino company tried to register the trademark in other areas of the world (they originally registered only in the US), and discovered that it was already registered in Italy. Negotiations with Martino and his firm to bring the trademark under control of the original Arduino company failed. In 2014, Smart Projects began refusing to pay royalties. They then appointed a new CEO, Federico Musto, who renamed the company Arduino SRL and created the website arduino.org, copying the graphics and layout of the original arduino.cc. This resulted in a rift in the Arduino development team.
At the World Maker Faire in New York on 1 October 2016, Arduino LLC co-founder and CEO Massimo Banzi and Arduino SRL CEO Federico Musto announced the merger of the two companies.
In April 2017, Wired reported that Musto had "fabricated his academic record... On his company"s website, personal LinkedIn accounts, and even on Italian business documents, Musto was, until recently, listed as holding a PhD from the Massachusetts Institute of Technology. In some cases, his biography also claimed an MBA from New York University." Wired reported that neither university had any record of Musto"s attendance, and Musto later admitted in an interview with Wired that he had never earned those degrees.open source licenses, schematics, and code from the Arduino website, prompting scrutiny and outcry.
By 2017 Arduino AG owned many Arduino trademarks. In July 2017 BCMI, founded by Massimo Banzi, David Cuartielles, David Mellis and Tom Igoe, acquired Arduino AG and all the Arduino trademarks. Fabio Violante is the new CEO replacing Federico Musto, who no longer works for Arduino AG.
In October 2017, Arduino announced its partnership with ARM Holdings (ARM). The announcement said, in part, "ARM recognized independence as a core value of Arduino ... without any lock-in with the ARM architecture". Arduino intends to continue to work with all technology vendors and architectures.
Under Violante"s guidance, the company started growing again and releasing new designs. The Genuino trademark was dismissed and all products were branded again with the Arduino name. As of February 2020, the Arduino community included about 30 million active users based on the IDE downloads.
In August 2018, Arduino announced its new open source command line tool (arduino-cli), which can be used as a replacement of the IDE to program the boards from a shell.
Arduino is open-source hardware. The hardware reference designs are distributed under a Creative Commons Attribution Share-Alike 2.5 license and are available on the Arduino website. Layout and production files for some versions of the hardware are also available.
Although the hardware and software designs are freely available under copyleft licenses, the developers have requested the name Arduino to be exclusive to the official product and not be used for derived works without permission. The official policy document on use of the Arduino name emphasizes that the project is open to incorporating work by others into the official product.-duino.
An early Arduino boardRS-232 serial interface (upper left) and an Atmel ATmega8 microcontroller chip (black, lower right); the 14 digital I/O pins are at the top, the 6 analog input pins at the lower right, and the power connector at the lower left.
Most Arduino boards consist of an Atmel 8-bit AVR microcontroller (ATmega8,ATmega328, ATmega1280, or ATmega2560) with varying amounts of flash memory, pins, and features.Arduino Due, based on the Atmel SAM3X8E was introduced in 2012.shields. Multiple and possibly stacked shields may be individually addressable via an I2C serial bus. Most boards include a 5 V linear regulator and a 16 MHz crystal oscillator or ceramic resonator. Some designs, such as the LilyPad,
Arduino microcontrollers are pre-programmed with a boot loader that simplifies uploading of programs to the on-chip flash memory. The default bootloader of the Arduino Uno is the Optiboot bootloader.RS-232 logic levels and transistor–transistor logic (TTL) level signals. Current Arduino boards are programmed via Universal Serial Bus (USB), implemented using USB-to-serial adapter chips such as the FTDI FT232. Some boards, such as later-model Uno boards, substitute the FTDI chip with a separate AVR chip containing USB-to-serial firmware, which is reprogrammable via its own ICSP header. Other variants, such as the Arduino Mini and the unofficial Boarduino, use a detachable USB-to-serial adapter board or cable, Bluetooth or other methods. When used with traditional microcontroller tools, instead of the Arduino IDE, standard AVR in-system programming (ISP) programming is used.
The Arduino board exposes most of the microcontroller"s I/O pins for use by other circuits. The Diecimila,Duemilanove,Unopulse-width modulated signals, and six analog inputs, which can also be used as six digital I/O pins. These pins are on the top of the board, via female 0.1-inch (2.54 mm) headers. Several plug-in application shields are also commercially available. The Arduino Nano, and Arduino-compatible Bare Bones Boardbreadboards.
Many Arduino-compatible and Arduino-derived boards exist. Some are functionally equivalent to an Arduino and can be used interchangeably. Many enhance the basic Arduino by adding output drivers, often for use in school-level education,
Arduino and Arduino-compatible boards use printed circuit expansion boards called shields, which plug into the normally supplied Arduino pin headers.3D printing and other applications, GNSS (satellite navigation), Ethernet, liquid crystal display (LCD), or breadboarding (prototyping). Several shields can also be made do it yourself (DIY).
Some shields offer stacking headers which allows multiple shields to be stacked on top of an Arduino board. Here, a prototyping shield is stacked on two Adafruit motor shield V2s.
A program for Arduino hardware may be written in any programming language with compilers that produce binary machine code for the target processor. Atmel provides a development environment for their 8-bit AVR and 32-bit ARM Cortex-M based microcontrollers: AVR Studio (older) and Atmel Studio (newer).
The Arduino integrated development environment (IDE) is a cross-platform application (for Microsoft Windows, macOS, and Linux) that is written in the Java programming language. It originated from the IDE for the languages brace matching, and syntax highlighting, and provides simple one-click mechanisms to compile and upload programs to an Arduino board. It also contains a message area, a text console, a toolbar with buttons for common functions and a hierarchy of operation menus. The source code for the IDE is released under the GNU General Public License, version 2.
The Arduino IDE supports the languages C and C++ using special rules of code structuring. The Arduino IDE supplies a software library from the Wiring project, which provides many common input and output procedures. User-written code only requires two basic functions, for starting the sketch and the main program loop, that are compiled and linked with a program stub main() into an executable cyclic executive program with the GNU toolchain, also included with the IDE distribution. The Arduino IDE employs the program avrdude to convert the executable code into a text file in hexadecimal encoding that is loaded into the Arduino board by a loader program in the board"s firmware.
From version 1.8.12, Arduino IDE windows compiler supports only Windows 7 or newer OS. On Windows Vista or older one gets "Unrecognized Win32 application" error when trying to verify/upload program. To run IDE on older machines, users can either use version 1.8.11, or copy "arduino-builder" executable from version 11 to their current install folder as it"s independent from IDE.
Most Arduino boards contain a light-emitting diode (LED) and a current-limiting resistor connected between pin 13 and ground, which is a convenient feature for many tests and program functions.Hello, World!, is "blink", which repeatedly blinks the on-board LED integrated into the Arduino board. This program uses the functions pinMode(), digitalWrite(), and delay(), which are provided by the internal libraries included in the IDE environment.
The open-source nature of the Arduino project has facilitated the publication of many free software libraries that other developers use to augment their projects.
This post is an introduction to the Nextion display with the Arduino. We’re going to show you how to configure the display for the first time, download the needed resources, and how to integrate it with the Arduino UNO board. We’ll also make a simple graphical user interface to control the Arduino pins.
Nextion is a Human Machine Interface (HMI) solution. Nextion displays are resistive touchscreens that makes it easy to build a Graphical User Interface (GUI). It is a great solution to monitor and control processes, being mainly applied to IoT applications.
The Nextion has a built-in ARM microcontroller that controls the display, for example it takes care of generating the buttons, creating text, store images or change the background. The Nextion communicates with any microcontroller using serial communication at a 9600 baud rate.
To design the GUI, you use the Nextion Editor, in which you can add buttons, gauges, progress bars, text labels, and more to the user interface in an easy way. We have the 2.8” Nextion display basic model, that is shown in the following figure.
Connecting the Nextion display to the Arduino is very straightforward. You just need to make four connections: GND, RX, TX, and +5V. These pins are labeled at the back of your display, as shown in the figure below.
You can power up the Nextion display directly from the Arduino 5V pin, but it is not recommended. Working with insufficient power supply may damage the display. So, you should use an external power source. You should use a 5V/1A power adaptor with a micro USB cable. Along with your Nextion display, you’ll also receive a USB to 2 pin connector, useful to connect the power adaptor to the display.
The best way to get familiar with a new software and a new device is to make a project example. Here we’re going to create a user interface in the Nextion display to control the Arduino pins, and display data.
The user interface has two pages: one controls two LEDs connected to the Arduino pins, and the other shows data gathered from the DHT11 temperature and humidity sensor;
We won’t cover step-by-step how to build the GUI in the Nextion display. But we’ll show you how to build the most important parts, so that you can learn how to actually build the user interface. After following the instructions, you should be able to complete the user interface yourself.
Additionally, we provide all the resources you need to complete this project. Here’s all the resources you need (be aware that you may need to change some settings on the user interface to match your display size):
We’ll start by adding a background image. To use an image as a background, it should have the exact same dimensions as your Nextion display. We’re using the 2.8” display, so the background image needs to be 240×320 pixels. Check your display dimensions and edit your background image accordingly. As an example, we’re using the following image:
Here you can select the font height, type, spacing and if you want it to be bold or not. Give it a name and click the Generate font button. After that, save the .zi file and add the generator font by clicking yes.
Note: At the time of writing this instructions there is an issue with font types. Whatever font type you chose, it will always look the same.Still, you can edit the font size and if it is bold or not.
At this moment, you can start adding components to the display area. For our project, drag three buttons, two labels and one slider, as shown in the figure below. Edit their looks as you like.
All components have an attribute called objname. This is the name of the component. Give good names to your components because you’ll need them later for the Arduino code. Also note that each component has one id number that is unique to that component in that page. The figure below shows the objname and id for the slider.
You should trigger an event for the touchable components (the buttons and the slider) so that the Arduino knows that a component was touched. You can trigger events when you press or when you release a component.
Our second page will display data from the DHT11 temperature and humidity sensor. We have several labels to hold the temperature in Celsius, the temperature in Fahrenheit, and the humidity. We also added a progress bar to display the humidity and an UPDATE button to refresh the readings. The bBack button redirects to page0.
Notice that we have labels to hold the units like “ºC”, “ºF” and “%”, and empty labels that will be filled with the readings when we have our Arduino code running.
Once the GUI is ready, you need to write the Arduino code so that the Nextion can interact with the Arduino and vice-versa. Writing code to interact with the Nextion display is not straightforward for beginners, but it also isn’t as complicated as it may seem.
A good way to learn how to write code for the Arduino to interact with the Nextion display is to go to the examples folder in the Nextion library folder and explore. You should be able to copy and paste code to make the Arduino do what you want.
The first thing you should do is to take note of your components in the GUI that will interact with the Arduino and take note of their ID, names and page. Here’s a table of all the components the code will interact to (your components may have a different ID depending on the order you’ve added them to the GUI).
Finally, you need a function for the bUpdate (the update button). When you click this button the DHT temperature and humidity sensor reads temperature and humidity and displays them on the corresponding labels, as well as the humidity on the progress bar. That is the bUpdatePopCallback() function.
In this post we’ve introduced you to the Nextion display. We’ve also created a simple application user interface in the Nextion display to control the Arduino pins. The application built is just an example for you to understand how to interface different components with the Arduino – we hope you’ve found the instructions as well as the example provided useful.
In our opinion, Nextion is a great display that makes the process of creating user interfaces simple and easy. Although the Nextion Editor has some issues and limitations it is a great choice for building interfaces for your electronics projects. We have a project on how to create a Node-RED physical interface with the Nextion display and an ESP8266 to control outputs. Feel free to take a look.