tft display graph free sample
Hi, nice article and I would like to be able to apply it to my idea of making a component testing curve tracer. Now it would normally use an analog oscilloscope set in the XY mode but it would be a way to bulky and space-hungry to my liking and that’s why an Arduino style 328P MCU made into a miniature oscilloscope (with a color TFT screen and XY inputs capable of withstanding up to 0.1 to 40Vp-p voltages would be a great candidate but have no idea how to do it since my programming skills are quite limited. Any help would be much appreciated TNX
The ST7789 TFT module contains a display controller with the same name: ST7789. It’s a color display that uses SPI interface protocol and requires 3, 4 or 5 control pins, it’s low cost and easy to use. This display is an IPS display, it comes in different sizes (1.3″, 1.54″ …) but all of them should have the same resolution of 240×240 pixel, this means it has 57600 pixels. This module works with 3.3V only and it doesn’t support 5V (not 5V tolerant).
The ST7789 display module shown in project circuit diagram has 7 pins: (from right to left): GND (ground), VCC, SCL (serial clock), SDA (serial data), RES (reset), DC (or D/C: data/command) and BLK (back light).
As mentioned above, the ST7789 TFT display controller works with 3.3V only (power supply and control lines). The display module is supplied with 3.3V (between VCC and GND) which comes from the Arduino board.
To connect the Arduino to the display module, I used voltage divider for each line which means there are 4 voltage dividers. Each voltage divider consists of 2.2k and 3.3k resistors, this drops the 5V into 3V which is sufficient.
The first library is a driver for the ST7789 TFT display which can be installed from Arduino IDE library manager (Sketch —> Include Library —> Manage Libraries …, in the search box write “st7789” and install the one from Adafruit).
Normally we show example of real-time reading things like DHT11 on monochrome LCD displays. We can graph that information. Graphing With Arduino on TFT LCD Color Display Probably a Needed Matter to Many Users. Graphing Can Become Difficult On Display With Less Known Drivers. Previously we have talked around MCUFRIEND TFT LCD Calculator. That one had problem with working codes. There are worse displays which are sold. Worse in the sense – most of the Arduino users need some easy working library which works with most common matters. This guide discuss some of the basic matters for the displays which use Elegoo Libraries (Adafruit Industries) and MCUFRIEND TFT LCD. The logic will be same for all similar displays but some tweaks needed for the others to make graph in proper orientation.
There are 3 main matters in the coding part – setting up graphing, reading value like temperature from DHT11 sensor, draw the graph. Unfortunately for practical purpose, you need to use board like Arduino Mega. Connecting DH11 with Arduino UNO is difficult as it occupies the whole board covering all pins. We are not always using the card reader but essentially it is difficult use the unused pins on Arduino UNO with such shield display.
Basically I purchased one Elegoo 2.8′ TFT LCD and was searching for graphing for some other reason. You can directly open this link to use in Arduino Web Editor. To use the same code on other boards, you need to modify some parts like :
In next article, we will see how we can graph values read by LDR on MCUFRIEND display. That is hopefully will be simple. Although with my model of MCUFRIEND TFT LCD, it not going to be easy to make it properly oriented.
This is a graphics library for the family of small colour TFT displays based on the ST7735 and ST7789 driver chips. These are really nice displays; bright, colourful, available in a variety of useful sizes, and available at low cost from suppliers like Adafruit, AliExpress, or Banggood:
This library allows you to plot points, draw lines, draw filled rectangles, and plot text with an optional scale factor. I"ve included a demo histogram-plotting program that adjusts itself to fit each of the displays I"ve supported.
Unlike most other TFT display libraries this one doesn"t require a memory buffer, allowing it to be run on any processor down to an ATtiny85. The displays are SPI and require four pins to drive the display, leaving one pin free on an ATtiny85 to interface to another device, such as a temperature sensor. If you need more pins choose a larger chip, such as the ATtiny84; see Using the library with other AVR chips at the end of the article for information about how to convert the code for different chips.
I"ve published a library for a colour OLED display in a previous article: Colour Graphics Library. The main difference between the colour TFT displays and the colour OLED displays is that the TFT displays are not self-illuminating, and so need a backlight; they therefore have a slightly higher power consumption. However, they are exceedingly cheap, and they are available in larger sizes than the colour OLED displays.
This library will work with displays based on the ST7735 which supports a maximum display size of 132 (H) x 162 (V), or the similar ST7789 which supports a maximum display size of 240 (H) x 320 (V).
The display driver interfaces to the displays with the longer side as the vertical dimension, which is why the rectangular displays are usually listed with the longer dimension second. My library allows you to rotate the image for any desired orientation.
All the Adafruit breakout boards for these displays include level-shifting circuitry, so they will work with either 5V or 3.3V microcontroller boards. They also include an SD card socket, if that"s of interest to you. The Adafruit boards have pullups on the backlight and reset pins, so the display will work if you leave these pins unconnected.
The pullup resistor from the display"s CS pin is optional; it holds the chip select high to prevent the display from being affected by the ISP signals while programming the ATtiny85.
The different displays are catered for by six constants which specify the size of the display, the offsets relative to the area supported by the display driver, whether the display is inverted, and the rotation value; for example:
Note that on some displays you may also have to change the xoff or yoff value when rotating the display. For example, to rotate the image on the 240x240 displays by 180° use the settings:
To check or adjust the values for each display I ran this program, which draws a one-pixel border around the display area, and plots an "F" to show the orientation:
The ATtiny85 and other AVR processors supports toggling of one or more bits in a port, so provided you set all the pins to their disabled state at startup, for speed the display access routines can simply toggle the appropriate pins to enable or disable them.
The InitDisplay() routine first defines the four display pins as outputs, and takes the SCK, DC, and CS pins high (inactive). It then sends the essential configuration commands to the display.
The display memory stores 18 bits per pixel: 6 bits per colour. However, you can write to the display in three alternative modes, with 12, 16, or 18 bits per pixel. I chose the 16 bit mode, which assigns 5 bits to red, 6 bits to green, and 5 bits blue. It"s the most convenient one to work with as you simply send two bytes to define the colour of each pixel.
To clear the display the ClearDisplay() routine sends the appropriate number of zero bytes. The routine temporarily switches to 12-bit colour mode, which reduces the time to clear the display by 25%:
The library includes basic graphics routines for plotting points and drawing lines. These work on a conventional coordinate system with the origin at lower left. For example, on the 80x160 display:
My first version of PlotChar() plotted characters by calling PlotPoint() for each pixel. However, I then tried the following alternative approach which defines an area of the display using the CASET (Column Address Set) and RASET (Row Address Set) commands, and then sends a stream of the appropriate bytes to define the character. This turned out to be over three times faster!
By default the ATtiny85 runs at 1MHz. Choose Burn Bootloader to set the fuses for 8MHz operation, or your graphics will run rather slowly, then upload the program using ISP (in-system programming).
14th January 2020: Tested the program with the Adafruit 1.3" 240x240 TFT display, and updated the program to correct a problem when rotating the image on that display.
This is a small graphics library, specifically aimed at ATtiny microcontrollers, for the variety of small colour TFT displays available at low cost from suppliers like Adafruit, AliExpress, or Banggood:
It"s an updated version of my Tiny TFT Graphics Library. This latest version of the library supports both the classic ATtiny processors, such as the ATtiny85, and the new 0-series, 1-series, and 2-series ATtiny processors, such as the ATtiny402. Like the original library it allows you to plot points, draw lines, draw filled rectangles, and plot characters and text with an optional scale factor, in 16-bit colour.
This version adds the ability to plot outline rectanges, and outline and filled circles. I"ve included demo curve-plotting and histogram-plotting programs that adjust to fit any display.
This library supports TFT displays that use an SPI interface and require four pins to drive the display. This leaves one pin free on an 8-pin chip such as the ATtiny85 or ATtiny402. If you need more pins choose a larger chip, such as the ATtiny84 or ATtiny404.
Unlike my Compact TFT Graphics Library which uses standard Arduino SPI calls, this library uses direct I/O pin manipulations. This means that you can use any assignment of pins to the four I/O lines needed by the display, and makes it about twice as fast as one using SPI calls. I"ve also added support for some additional displays, so it now supports 16 different TFT displays.
So provided you set all the pins to their disabled state at startup, the display routines can simply toggle the appropriate pins to enable or disable them.
The differences between each family of processors are handled by constants to define the pin assignments, and preprocessor macros to define the bit manipulations. If you use the circuits given below you won"t need to change anything, apart from specifying which display you"re using.
The ClearDisplay() routine has been optimised further by realising that we don"t need to keep setting the mosi bit, since to clear the display it is always zero, so the routine only needs to toggle the sck bit the appropriate number of times. I"m grateful to Thomas Scherer for suggesting this.
This library will work with displays based on the ST7735 which supports a maximum display size of 162x132, or the ST7789 and ILI9340/1 which support a maximum display size of 320x240. It includes parameters for the following colour TFT displays:
* These Adafruit displays conveniently all have the same edge-connector layout, so you can make a prototyping board or PCB that will take any of them, such as my Universal TFT Display Backpack.
Some of the AliExpress displays include a LDO 3.3V regulator, but not logic-level translation, so I recommend only interfacing them to a processor running from 3.3V.
The Adafruit displays all include an LDO 3.3V regulator and logic-level translation, so can be safely interfaced to processors powered from either 5V or 3.3V.
On the AliExpress red 160x128 display you need to connect the backlight pin to Vcc to turn it on. This doesn"t seem to be necessary with the other displays.
The library will probably support other TFT displays that use the same ST7735, ST7789, ILI9340/1 driver chips, but you may need to experiment with the parameters to get the image scaled and centered correctly.
The display needs to be connected to the microcontroller via four I/O lines: MOSI, SCK, CS, and DC. You can use any pins for these, but they should all be in the same port. You need to specify the port pin numbers of the pins you are using at the start of the Tiny TFT Graphics Library listing.
The 33kΩ pullup resistor from the display"s CS pin is optional; it is only needed on the AliExpress displays, and holds the chip select high to prevent the display from flickering while programming the ATtiny85.
The different displays are catered for by seven constants which specify the size of the display, the offsets relative to the area supported by the display driver, whether the display is inverted, the rotation value, and the order of the colours; for example:
By default the parameters give the correct orientation assuming you"re using the display with the header pins along the top, except in the case of the larger displays which have the header pins along the shorter edge, in which case the header pins are assumed to be on the left.
To check or adjust the values for each display you can run the TestChart() program, which draws a one-pixel border around the display area, and plots a red "F" to show the orientation:
The library will probably support other TFT displays that use the same driver chips, but you may need to experiment with the parameters to get the image scaled and centered correctly.
The library includes basic graphics routines for plotting points and drawing lines. These work on a conventional coordinate system with the origin at lower left. For example, on the 80x160 display:
By default the ATtiny85 runs at 1MHz. Choose Burn Bootloader to set the fuses for 8MHz operation, or your graphics will run rather slowly, then upload the program using an ISP (in-system programming) programmer such as Sparkfun"s Tiny AVR Programmer Board
AndyPi’s latest product is a miniature colour graphic TFT display, 2.2″ wide with 320×240 pixels (we also have a small number of 1.8″ TFT’s at a bargain price) The sky is the limit as to what you could use this for – its more flexible that our HD44780 LCDs, but a little more complicated to set up (only a little!). The drivers have been designed by Raspberry Pi forum member notro (see details here) and other instruction are available on the forums, but you’ll also find full (well… currently under construction) step by step set of instructions here on the following topics:
3. 9-way cable for GPIO & power connection; leaves other pins free, and gives 20 cm cable length to position the display in different case shapes to your own preference.
A. Download fresh image of the latest version of Raspbian (tested with 2015-02-16) by Notro with the FBTFT drivers available as loadable modules. (2014-06-20-wheezy-raspbian-2014-07-25-fbtft-master-firmware.zip) https://github.com/notro/fbtft/wiki#image-download).
Write this image to your SD card, and the SSH into your Pi from another computer so you can complete the setup. There are further details on this page which are worth checking out. You then need to update the kernel, which now includes the TFT drivers as standard:
add this new line at the end: fbtft_device custom name=fb_ili9341 gpios=reset:25,dc:24,led:18 speed=16000000 bgr=1 rotate=270(for 2.2″ screen, or name=adafruit22a)or add this new line at the end: fbtft_device name=sainsmart18 rotate=270(for 1.8″ screen)
It’s worth knowing that the screen will go blank after 30 minutes to protect it, if there has been no activity on it (actually important on these small TFTs). Check out this informationif you need to change it.
NOTE (25/112015): This command is not working on latest versions of Raspbian as it hardwires x to use fb0. Please see this pagefor tips on how to edit your settings to get displaying on the TFT.
An excellent new compatible library is available which can render TrueType fonts on a TFT screen (or into a sprite). This has been developed by takkaO and is available here. I have been reluctant to support yet another font format but this is an amazing library which is very easy to use. It provides access to compact font files, with fully scaleable anti-aliased glyphs. Left, middle and right justified text can also be printed to the screen. I have added TFT_eSPI specific examples to the OpenFontRender library and tested on RP2040 and ESP32 processors, however the ESP8266 does not have sufficient RAM. Here is a demo screen where a single 12kbyte font file binary was used to render fully anti-aliased glyphs of gradually increasing size on a 320x480 TFT screen:
For ESP32 ONLY, the TFT configuration (user setup) can now be included inside an Arduino IDE sketch providing the instructions in the example Generic->Sketch_with_tft_setup are followed. See ReadMe tab in that sketch for the instructions. If the setup is not in the sketch then the library settings will be used. This means that "per project" configurations are possible without modifying the library setup files. Please note that ALL the other examples in the library will use the library settings unless they are adapted and the "tft_setup.h" header file included. Note: there are issues with this approach, #2007 proposes an alternative method.
Support has been added in v2.4.70 for the RP2040 with 16 bit parallel displays. This has been tested and the screen update performance is very good (4ms to clear 320 x 480 screen with HC8357C). The use of the RP2040 PIO makes it easy to change the write cycle timing for different displays. DMA with 16 bit transfers is also supported.
Smooth fonts can now be rendered direct to the TFT with very little flicker for quickly changing values. This is achieved by a line-by-line and block-by-block update of the glyph area without drawing pixels twice. This is a "breaking" change for some sketches because a new true/false parameter is needed to render the background. The default is false if the parameter is missing, Examples:
New anti-aliased graphics functions to draw lines, wedge shaped lines, circles and rounded rectangles. Examples are included. Examples have also been added to display PNG compressed images (note: requires ~40kbytes RAM).
Frank Boesing has created an extension library for TFT_eSPI that allows a large range of ready-built fonts to be used. Frank"s library (adapted to permit rendering in sprites as well as TFT) can be downloaded here. More than 3300 additional Fonts are available here. The TFT_eSPI_ext library contains examples that demonstrate the use of the fonts.
Users of PowerPoint experienced with running macros may be interested in the pptm sketch generator here, this converts graphics and tables drawn in PowerPoint slides into an Arduino sketch that renders the graphics on a 480x320 TFT. This is based on VB macros created by Kris Kasprzak here.
The RP2040 8 bit parallel interface uses the PIO. The PIO now manages the "setWindow" and "block fill" actions, releasing the processor for other tasks when areas of the screen are being filled with a colour. The PIO can optionally be used for SPI interface displays if #define RP2040_PIO_SPI is put in the setup file. Touch screens and pixel read operations are not supported when the PIO interface is used.
DMA can now be used with the Raspberry Pi Pico (RP2040) when used with both 8 bit parallel and 16 bit colour SPI displays. See "Bouncy_Circles" sketch.
The library now supports the Raspberry Pi Pico with both the official Arduino board package and the one provided by Earle Philhower. The setup file "Setup60_RP2040_ILI9341.h" has been used for tests with an ILI9341 display. At the moment only SPI interface displays have been tested. SPI port 0 is the default but SPI port 1 can be specifed in the setup file if those SPI pins are used.
The library now provides a "viewport" capability. See "Viewport_Demo" and "Viewport_graphicstest" examples. When a viewport is defined graphics will only appear within that window. The coordinate datum by default moves to the top left corner of the viewport, but can optionally remain at top left corner of TFT. The GUIslice library will make use of this feature to speed up the rendering of GUI objects (see #769).
An Arduino IDE compatible graphics and fonts library for 32 bit processors. The library is targeted at 32 bit processors, it has been performance optimised for STM32, ESP8266 and ESP32 types. The library can be loaded using the Arduino IDE"s Library Manager. Direct Memory Access (DMA) can be used with the ESP32, RP2040 and STM32 processors with SPI interface displays to improve rendering performance. DMA with a parallel interface is only supported with the RP2040.
For other processors the generic only SPI interface displays are supported and slower non-optimised standard Arduino SPI functions are used by the library.
"Four wire" SPI and 8 bit parallel interfaces are supported. Due to lack of GPIO pins the 8 bit parallel interface is NOT supported on the ESP8266. 8 bit parallel interface TFTs (e.g. UNO format mcufriend shields) can used with the STM32 Nucleo 64/144 range or the UNO format ESP32 (see below for ESP32).
The library supports some TFT displays designed for the Raspberry Pi (RPi) that are based on a ILI9486 or ST7796 driver chip with a 480 x 320 pixel screen. The ILI9486 RPi display must be of the Waveshare design and use a 16 bit serial interface based on the 74HC04, 74HC4040 and 2 x 74HC4094 logic chips. Note that due to design variations between these displays not all RPi displays will work with this library, so purchasing a RPi display of these types solely for use with this library is not recommended.
A "good" RPi display is the MHS-4.0 inch Display-B type ST7796 which provides good performance. This has a dedicated controller and can be clocked at up to 80MHz with the ESP32 (55MHz with STM32 and 40MHz with ESP8266). The MHS-3.5 inch RPi ILI9486 based display is also supported.
Some displays permit the internal TFT screen RAM to be read, a few of the examples use this feature. The TFT_Screen_Capture example allows full screens to be captured and sent to a PC, this is handy to create program documentation.
The library supports Waveshare 2 and 3 colour ePaper displays using full frame buffers. This addition is relatively immature and thus only one example has been provided.
The library includes a "Sprite" class, this enables flicker free updates of complex graphics. Direct writes to the TFT with graphics functions are still available, so existing sketches do not need to be changed.
A Sprite is notionally an invisible graphics screen that is kept in the processors RAM. Graphics can be drawn into the Sprite just as they can be drawn directly to the screen. Once the Sprite is completed it can be plotted onto the screen in any position. If there is sufficient RAM then the Sprite can be the same size as the screen and used as a frame buffer. Sprites by default use 16 bit colours, the bit depth can be set to 8 bits (256 colours) , or 1 bit (any 2 colours) to reduce the RAM needed. On an ESP8266 the largest 16 bit colour Sprite that can be created is about 160x128 pixels, this consumes 40Kbytes of RAM. On an ESP32 the workspace RAM is more limited than the datasheet implies so a 16 bit colour Sprite is limited to about 200x200 pixels (~80Kbytes), an 8 bit sprite to 320x240 pixels (~76kbytes). A 1 bit per pixel Sprite requires only 9600 bytes for a full 320 x 240 screen buffer, this is ideal for supporting use with 2 colour bitmap fonts.
One or more sprites can be created, a sprite can be any pixel width and height, limited only by available RAM. The RAM needed for a 16 bit colour depth Sprite is (2 x width x height) bytes, for a Sprite with 8 bit colour depth the RAM needed is (width x height) bytes. Sprites can be created and deleted dynamically as needed in the sketch, this means RAM can be freed up after the Sprite has been plotted on the screen, more RAM intensive WiFi based code can then be run and normal graphics operations still work.
Drawing graphics into a sprite is very fast, for those familiar with the Adafruit "graphicstest" example, this whole test completes in 18ms in a 160x128 sprite. Examples of sprite use can be found in the "examples/Sprite" folder.
The "Animated_dial" example shows how dials can be created using a rotated Sprite for the needle. To run this example the TFT interface must support reading from the screen RAM (not all do). The dial rim and scale is a jpeg image, created using a paint program.
The XPT2046 touch screen controller is supported for SPI based displays only. The SPI bus for the touch controller is shared with the TFT and only an additional chip select line is needed. This support will eventually be deprecated when a suitable touch screen library is available.
The library supports SPI overlap on the ESP8266 so the TFT screen can share MOSI, MISO and SCLK pins with the program FLASH, this frees up GPIO pins for other uses. Only one SPI device can be connected to the FLASH pins and the chips select for the TFT must be on pin D3 (GPIO0).
The library is based on the Adafruit GFX and Adafruit driver libraries and the aim is to retain compatibility. Significant additions have been made to the library to boost the speed for the different processors (it is typically 3 to 10 times faster) and to add new features. The new graphics functions include different size proportional fonts and formatting features. There are lots of example sketches to demonstrate the different features and included functions.
Configuration of the library font selections, pins used to interface with the TFT and other features is made by editing the User_Setup.h file in the library folder, or by selecting your own configuration in the "User_Setup_Selet,h" file. Fonts and features can easily be enabled/disabled by commenting out lines.
It would be possible to compress the vlw font files but the rendering performance to a TFT is still good when storing the font file(s) in SPIFFS, LittleFS or FLASH arrays.
Anti-aliased fonts can also be drawn over a gradient background with a callback to fetch the background colour of each pixel. This pixel colour can be set by the gradient algorithm or by reading back the TFT screen memory (if reading the display is supported).
The common 8 bit "Mcufriend" shields are supported for the STM Nucleo 64/144 boards and ESP32 UNO style board. The STM32 "Blue/Black Pill" boards can also be used with 8 bit parallel displays.
Unfortunately the typical UNO/mcufriend TFT display board maps LCD_RD, LCD_CS and LCD_RST signals to the ESP32 analogue pins 35, 34 and 36 which are input only. To solve this I linked in the 3 spare pins IO15, IO33 and IO32 by adding wires to the bottom of the board as follows:
If the display board is fitted with a resistance based touch screen then this can be used by performing the modifications described here and the fork of the Adafruit library:
If you load a new copy of TFT_eSPI then it will overwrite your setups if they are kept within the TFT_eSPI folder. One way around this is to create a new folder in your Arduino library folder called "TFT_eSPI_Setups". You then place your custom setup.h files in there. After an upgrade simply edit the User_Setup_Select.h file to point to your custom setup file e.g.:
The library was intended to support only TFT displays but using a Sprite as a 1 bit per pixel screen buffer permits support for the Waveshare 2 and 3 colour SPI ePaper displays. This addition to the library is experimental and only one example is provided. Further examples will be added.
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 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.
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.
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.
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.
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.
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().
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.
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.
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().
My latest project as an amateur designer has a BME280 sensor generating temperature, humidity and air pressure data at set time periods. These three sets of data are saved in 3 x arrays over a 24 hour period with the sampling every 7-8 minutes producing around 195 data points over 24 hours. I am coding in C on a PIC32 and displaying on a 320 x 240 TFT, my attempt at a graph showing temp is attached. So far I have plotted simple y axis values to generate a line graph, see pic, the graph is updated with the latest temperature reading on the right hand side and the graph line then moves one sample point to the left and is redrawn, this part works OK. I use an equation relating to the temperature at two known levels and where they should be shown on the graph, all graphing points are calculated for each array temperature value and then displayed.
So on to my question and request for help, I would like to scale the graph and show more of the rises and falls in temperature without distorting the total graph line, or it"s overall Y axis value. I have tried a number of ways to do this, latest is to take the average of all the temperature readings in the temperature array and use this as a base line to monitor rises and falls, then only for these changes add a scaling factor. So far my scaling factor is fixed at x 2, doing this displays more changes in the y axis but introduces a problem as the average also changes as new temperature readings are taken and therefore moves this average base line. The scaling needs to work for temps declining or rising over many hours, or both, but some how still showing the line in the correct position on the graph. I hope this makes some sense and any ideas / feedback are welcome. With no scaling the graph line is displayed OK but smaller changes in temperature are hard to see. As I plan to read outside temperatures the y axis is from -20 to + 50C as shown.
BTW I have a lot of variable values on the being shown on the RHS of display as an easy way to see what is happening with the code producing the graph line and scaling.