160 x 128 tft display free sample
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.
High level commands set (61 commands total) are easy to remember and understand, eg.: send 5 bytes: "CCabc" will draw a ratio=c pixels circle at coordinate (a,b) on the screen; 5 bytes "DNALL" will put the module to sleep mode(<0.1mA), and more...
This new library is a standalone library that contains the TFT driver as well as the graphics functions and fonts that were in the GFX library. This library has significant performance improvements when used with an UNO (or ATmega328 based Arduino) and MEGA.
Examples are included with the library, including graphics test programs. The example sketch TFT_Rainbow_one shows different ways of using the font support functions. This library now supports the "print" library so the formatting features of the "print" library can be used, for example to print to the TFT in Hexadecimal, for example:
To use the F_AS_T performance option the ILI9341 based display must be connected to an MEGA as follows:MEGA +5V to display pin 1 (VCC) and pin 8 (LED) UNO 0V (GND) to display pin 2 (GND)
TFT_ILI9341 library updated on 1st July 2015 to version 12, this latest version is attached here to step 8:Minor bug when rendering letter "T" in font 4 without background fixed
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.
I wrote an initial version of this library in uLisp, my Lisp interpreter for microcontrollers, which made it easy to experiment with different approaches. I then converted it to C to run on an ATtiny85. I can publish the uLisp version if anyone"s interested.
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 boards available from AliExpress or Banggood are generally 3.3V only. If you"re using them with a 5V microcontroller you need to include a regulator and level-shifting circuitry.
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.
The foreground and background colours are defined by the two global variables fore and back. Initially these are set to 0xFFFF, white, and 0, black, respectively:
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!
The default value of scale is 1, but you can change it to plot larger characters. After plotting a character PlotChar() moves the plot position to the start of the next character to make it easy to plot several characters in a row without needing to callMoveTo().
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 compact graphics library that supports a range of different colour TFT displays, such as the displays from Adafruit and AliExpress. It uses standard Arduino SPI calls making it compatible with a variety of different boards and processors:
It supports plotting points and drawing lines, drawing filled rectangles, and plotting characters and text in 16-bit colour. The library occupies less than 4K bytes, including the character set and demo program, and so will fit on microcontrollers with 4K flash such as the ATtiny45, ATtiny402, and ATtiny412.
In my earlier article Tiny TFT Graphics Library I described a small graphics library designed for driving a variety of TFT displays from an ATtiny85. This library is an extension of that program, with the following enhancements:
* 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.
Some of the AliExpress displays include a LDO 3.3V regulator, but as far as I can tell none of them include 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 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 or ST7789 driver chips, but you may need to experiment with the parameters to get the image scaled and centered correctly.
Two of these, Data In and Clock, are dictated by the SPI interface on the processor you are using. They are usually called MOSI and SCK on the pinout diagram, and they connect to the appropriate two pins on the display.
For the other two signals, Chip Select and Data/Command, you can use any two spare I/O lines on the processor. You need to specify the Arduino pin numbers of the two pins you are using at the start of the Compact TFT Graphics Library listing; for example, to use the ATtiny402 circuit below:
The foreground and background colours are defined by the two global variables fore and back. Initially these are set to 0xFFFF, white, and 0, black, respectively:
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:
You can plot larger characters by setting the global variable scale, default value 1. After plotting a character PlotChar() moves the plot position to the start of the next character to make it easy to plot several characters in a row without needing to call MoveTo().
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:
Hi guys, welcome to today’s tutorial. Today, we will look on how to use the 1.8″ ST7735 colored TFT display with Arduino. The past few tutorials have been focused on how to use the Nokia 5110 LCD display extensively but there will be a time when we will need to use a colored display or something bigger with additional features, that’s where the 1.8″ ST7735 TFT display comes in.
The ST7735 TFT display is a 1.8″ display with a resolution of 128×160 pixels and can display a wide range of colors ( full 18-bit color, 262,144 shades!). The display uses the SPI protocol for communication and has its own pixel-addressable frame buffer which means it can be used with all kinds of microcontroller and you only need 4 i/o pins. To complement the display, it also comes with an SD card slot on which colored bitmaps can be loaded and easily displayed on the screen.
The schematics for this project is fairly easy as the only thing we will be connecting to the Arduino is the display. Connect the display to the Arduino as shown in the schematics below.
Due to variation in display pin out from different manufacturers and for clarity, the pin connection between the Arduino and the TFT display is mapped out below:
We will use two libraries from Adafruit to help us easily communicate with the LCD. The libraries include the Adafruit GFX library which can be downloaded here and the Adafruit ST7735 Library which can be downloaded here.
We will use two example sketches to demonstrate the use of the ST7735 TFT display. The first example is the lightweight TFT Display text example sketch from the Adafruit TFT examples. It can be accessed by going to examples -> TFT -> Arduino -> TFTDisplaytext. This example displays the analog value of pin A0 on the display. It is one of the easiest examples that can be used to demonstrate the ability of this display.
The second example is the graphics test example from the more capable and heavier Adafruit ST7735 Arduino library. I will explain this particular example as it features the use of the display for diverse purposes including the display of text and “animated” graphics. With the Adafruit ST7735 library installed, this example can be accessed by going to examples -> Adafruit ST7735 library -> graphics test.
Next, we create an object of the library with the pins to which the LCD is connected on the Arduino as parameters. There are two options for this, feel free to choose the most preferred.
Next, we move to the void setup function where we initialize the screen and call different test functions to display certain texts or images. These functions can be edited to display what you want based on your project needs.
testdrawtext("Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur adipiscing ante sed nibh tincidunt feugiat. Maecenas enim massa, fringilla sed malesuada et, malesuada sit amet turpis. Sed porttitor neque ut ante pretium vitae malesuada nunc bibendum. Nullam aliquet ultrices massa eu hendrerit. Ut sed nisi lorem. In vestibulum purus a tortor imperdiet posuere. ", ST7735_WHITE);
All the functions called under the void setup function, perform different functions, some draw lines, some, boxes and text with different font, color and size and they can all be edited to do what your project needs.
The complete code for this is available under the libraries example on the Arduino IDE. Don’t forget to change the DC and the RESET pin configuration in the code to match the schematics.
Uploading the code to the Arduino board brings a flash of different shapes and text with different colors on the display. I captured one and its shown in the image below.
That’s it for this tutorial guys, what interesting thing are you going to build with this display? Let’s get the conversation started. Feel free to reach me via the comment section if you have any questions as regards this project.
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The 1.8 inch TFT LCD Module SPI Serial 51 128 x 160 is a compact colourful display that works well with Raspberry Pi, Android and other microcontrollers.
The display module is bight, anti-reflective and offers the choice of loading images via SD card through the slot on the back of the screen or via a microcontroller.
16-BIT RGB 65K colour display and the internal driver IC is ST7735S, which uses 4-wire SPI communication. The module contains an LCD display and a PCB control backplane.
It only takes a few IOs to illuminate the display with an SD card slot for convenient function expansion provide underlying libraries and rich sample programs forArduino, C51, and STM32 platforms.
The TFT module is the heart of this product -- it contains all the subsystems that are required to make an image show up. Starting with one of the most obvious features; the LCD screen is a glass panel with small little cells of liquid crystal (LC) material that can be shifted from opaque to clear with an electronic signal (more on how LCDs work). For each of the 128x160 pixels in the screen there are three LC cells and each cell has either a red, green, or blue filter in it to color the light. A pixel gets colored when white light from the LED backlight passes through the filtered cells in varying amounts.
The amount of light passed through is controlled by the signal applied to the liquid crystal cells, but the sheer number of pins and complexity of those signals is totally impractical to control directly with a microcontroller. Fortunately some really smart cookies created a dedicated driver Integrated Circuit (IC) that stores pixel data and puts it on the screen for us. Connections to the driver, as well as the backlight, are broken out along a flexible flat printed circuit (FPC) cable - and that"s where we take over.
The FPC connector is convenient for two reasons. First, it"s extremely simple to (re)connect the display to the breakout board. Second, production of this product is made easier because all soldering can be done in our normal surface mount process.
To disconnect the TFT module just flip up the black locking bar with a finger or pair of tweezers and then gently pull the cable straight out from the connector. To put the cable back in, first make sure that the polarity indicators on the cable (1, 40) match up with those on the board and that the black locking bar is flipped up. Next push the cable in evenly for about 2mm.
The microSD card holder is there to relieve your microcontroller"s poor memory due to having to store hundreds of images of cats, or really whatever you want to keep there. The SD card is connected to the same SPI bus as the display, which in turn keeps the required pin count low.
Out of the box, the TFT will come with a large backing PCB that makes it easy to securely mount the display in a project. If you need a more flexible solution you can remove the display module, snap off half the backing board, and then re-insert the display module. When this is done you"ll be left with the bare minimum frame around the display to more seamlessly integrate with your project.
The pinout of this breakout includes the standard SPI interfaces for both the TFT and the microSD card as well as a few specialty pins. You can power the breakout with either 5V or 3.3V thanks to the onboard voltage regulator and level shifter.
D/C : This is a special signal found in many display controllers. When it is high the incoming data is interpreted as data as opposed to commands when it is low.
TE : Tearing Effect is an optional output from the display to synchronize data writes - to avoid the "Tearing Effect" that is seen when data is changed halfway through a screen refresh
I wanted to see how far I could push the Cortex M0+ of the Arduino Zero. I think it is a balanced microcontroller: not too limited like an AVR, not too fancy, like a Cortex M4 (which has enough computing power even to run Doom).
Initially I went on the conservative way: the ATSAMD21 specifies a maximum SPI frequency of about 12MHz, and by specification, the ST7735 controller allows a maximum SPI frequency of 15MHz (66ns SCLK time). Therefore I set the SPI frequency to 12 MHz and I also fixed the frame rate to 25 fps (without cap, the refresh frequency fluctuated from 28 to 33 Hz. I wanted to save a couple of fps because I will need to implement the sound later).
However I have recently realized that both the display and the ATSAMD21 can work at 24 MHz! That"s a good overclock amount! (still the CPU is not overclocked!)
Yes, the ATSAMD21 is quite powerful. Enough powerful? It is a 48 MHz Cortex M0+, with a good DMA engine. Let’s make a ballpark calculations. The 48MHz frequency means that we have about 93 clock cycles per each pixel, at 25 fps....
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. 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:
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.
Support for the ESP32-S2, ESP32-S3 and ESP32-C3 has been added (DMA not supported at the moment). Tested with v2.0.3 RC1 of the ESP32 board package. Example setups:
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.
If an ESP32 board has SPIRAM (i.e. PSRAM) fitted then Sprites will use the PSRAM memory and large full screen buffer Sprites can be created. Full screen Sprites take longer to render (~45ms for a 320 x 240 16 bit Sprite), so bear that in mind.
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.
The .vlw files must be uploaded to the processors FLASH filing system (SPIFFS, LittleFS or SD card) for use. Alternatively the .vlw files can be converted to C arrays (see "Smooth Font -> FLASH_Array" examples) and stored directly in FLASH as part of the compile process. The array based approach is convenient, provides performance improvements and is suitable where: either use of a filing system is undesirable, or the processor type (e.g. STM32) does not support a FLASH based filing system.
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.:
You can take this one step further and have your own setup select file and then you only need to replace the Setup.h line reference in User_Setup_Select.h to, for example:
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.
Recently, I had the idea to make a digital picture frame—one of these kinds which load images from SD cards and show each image for some time. I was remembering myself that I already own a small TFT display, the KMR-1.8 SPI, that works out of the box with an Arduino Uno. When I digged up my KMR-1.8 SPI, I realized that it has also an in-built SD card reader. Moreover, I looked up the Internet and found ready-to-use libraries for the in-built SD card reader as well as showing images on the TFT display. For these reasons, I thought making such an digital picture frame will turn out very easy.
When I started to implement my first lines of codes and started to connect my Arduino Uno to the KMR-1.8 SPI, I ran into two major problems. First, the colors of my image file did not match to the colors displayed by the KMR-1.8 (red and blue were interchanged). Second, my first prototypes stopped to work after about 5 minutes. The application started to freeze and showed the same image forever instead of displaying the next image after a chosen time.
I did some research on the Internet and I found out that many people ran into similar problems. The second problem seemed to be caused by some memory leaks in the code. Nevertheless, I did not came across any example code that worked out of the box for my setup. Therefore, I want to share how I made it work.
There exists various versions of so-called “1.8 TFT displays” from different manufacturers. Not all of them are 100% compatible to each other. Therefore, if you own a TFT display and want to use my tutorial to make it work, please check if your TFT display really matches the version I used in this tutorial:
The source code relies on three header files (and libraries): SPI.h (Link), SD.h (Link) and TFT.h (Link). Please make sure that all of them are correctly installed before trying out my source code (In Arduino IDE: Tools -> Manage Libraries…).
In the introduction of this blog post, I mentioned that I came across two major problems: the colors red and blue were interchanged and my early Arduino programs started to freeze after some time. Luckily, I was able to fix all issues. The following source code works perfect on my setup. My “digital picture frame” does not require to be restarted after some time (my long-term test lasted about two weeks—and no restart was necessary).
I overcame the first problem by not using the default initialization method (“TFTscreen.begin();”) of the TFT library. Instead, I looked up whats inside the “begin”-method. I found a method called “initR” which has a parameter that allows to perform the initialization for a specific chip. Here, the parameter value “INITR_BLACKTAB” worked for me as the colors were then shown correctly. In addition, I call the method “setRotation” with parameter value “1” in order to be conform to the default initialization method. In the end, the code for the setting up the TFT library object looks like this:// ...
The code looks for image files (*.BMP) on the SD card and shows each image for 60 seconds. You can change the display time by setting “DELAY_IMAGE_SWAP” to a new value.
Important Note: The image files on the SD card must be stored as BMP with a resolution of 160x128 pixels (width x height). Moreover, long file names and special characters must be avoided.