esp32 tft display library made in china

TFT_display_init() Perform display initialization sequence. Sets orientation to landscape; clears the screen. SPI interface must already be setup, tft_disp_type, _width, _height variables must be set.

compile_font_file Function which compiles font c source file to binary font file which can be used in TFT_setFont() function to select external font. Created file has the same name as source file and extension .fnt

The TFT display is a kind of LCD that is connected to each pixel using a transistor and it features low current consumption, high-quality, high-resolution and backlight. This 2.8-inch full color LCD has a narrow PCB display. The resolution is 320×280 pixels and it has a four-wire SPI interface and white backlight.

While I was looking for a TFT display for a project with Arduino, I found on several webstores some displays based on the ST7735 chip by Sitronix (datasheet).

Based on its datasheet, the ST7735 chip has a SPI (Serial Peripheral Interface) interface, but the pin names on the silk screen of my display “seem” to suggest an I2C interface (SDA, SCL…):

Adafruit wrote a fantastic tutorial to explain how to use them, here I only want to show you how to setup the display for the connections I made earler:

If you’re using a board based on the esp32 chip and you need to display bitmap images, give a look to my library, SPIFFS_ImageReader, which perfectly integrates with the ones by Adafruit!

You may be getting ground bounce issues due to long wires between the boards. Try adding extra 0V (GND) connections and keep all the wires as short as possible. The best option is to use an UNO style ESP32 board with the display as this is a tested combination that is less error prone.

Unfortunately the typical UNO/mcufriend TFT display board maps LCD_RD, LCD_CS and LCD_RST signals to the ESP32 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:

ESP-LCD is a multimedia smart-control solution built around ESP32-S2-HMI-DevKit-1 and an LCD capacitive touch screen. With ESP-LCD, users can easily realize a hardware network, and achieve remote or smart-touch control, data visualization, music playback, recording, etc. ESP-LCD is suitable for several smart-control scenarios involving smart clocks, air-quality detectors, smart audio control, and various other applications based on touch screens.

ESP32-S2-HMI-DevKit-1 is a development board based on the ESP32-S2-WROVER module. It has a 4.3-inch TFT-LCD, and a capacitive touch panel with a resolution of up to 480×800 and an initial start-up time that is less than 200 ms. ESP32-S2-HMI-DevKit-1 has various components, including a light sensor, a temperature and humidity sensor, a MEMS sensor, a micro-SD card connector, a TWAI® interface (compatible with CAN 2.0) etc. On top of that, it also supports functions, such as LVGL GUI development, music playback, and recording.

Based on ESP-IDF, users can easily migrate their applications to other ESP SoCs. The complete C runtime library enables users to seamlessly switch from any PC platform to ESP-IDF in order to use standard input and output, memory allocation, file system, and other functions.

We have used Liquid Crystal Displays in the DroneBot Workshop many times before, but the one we are working with today has a bit of a twist – it’s a circle!  Perfect for creating electronic gauges and special effects.

LCD, or Liquid Crystal Displays, are great choices for many applications. They aren’t that power-hungry, they are available in monochrome or full-color models, and they are available in all shapes and sizes.

Today we will see how to use this display with both an Arduino and an ESP32. We will also use a pair of them to make some rather spooky animated eyeballs!

There are also some additional connections to the display. One of them, DC, sets the display into either Data or Command mode. Another, BL, is a control for the display’s backlight.

The above illustration shows the connections to the display.  The Waveshare display can be used with either 3.3 or 5-volt logic, the power supply voltage should match the logic level (although you CAN use a 5-volt supply with 3.3-volt logic).

Another difference is simply with the labeling on the display. There are two pins, one labeled SDA and the other labeled SCL. At a glance, you would assume that this is an I2C device, but it isn’t, it’s SPI just like the Waveshare device.

This display can be used for the experiments we will be doing with the ESP32, as that is a 3.3-volt logic microcontroller. You would need to use a voltage level converter if you wanted to use one of these with an Arduino Uno.

The Waveshare device comes with a cable for use with the display. Unfortunately, it only has female ends, which would be excellent for a Raspberry Pi (which is also supported) but not too handy for an Arduino Uno. I used short breadboard jumper wires to convert the ends into male ones suitable for the Arduino.

Once you have everything hooked up, you can start coding for the display. There are a few ways to do this, one of them is to grab the sample code thatWaveshare provides on their Wiki.

The Waveshare Wiki does provide some information about the display and a bit of sample code for a few common controllers. It’s a reasonable support page, unfortunately, it is the only support that Waveshare provides(I would have liked to see more examples and a tutorial, but I guess I’m spoiled by Adafruit and Sparkfun LOL).

Open the Arduino folder. Inside you’ll find quite a few folders, one for each display size that Waveshare supports. As I’m using the 1.28-inch model, I selected theLCD_1inch28folder.

You can see from the code that after loading some libraries we initialize the display, set its backlight level (you can use PWM on the BL pin to set the level), and paint a new image. We then proceed to draw lines and strings onto the display.

After uploading the code, you will see the display show a fake “clock”. It’s a static display, but it does illustrate how you can use this with the Waveshare code.

This library is an extension of the Adafruit GFX library, which itself is one of the most popular display libraries around. Because of this, there isextensive documentation for this libraryavailable from Adafruit.  This makes the library an excellent choice for those who want to write their own applications.

As with the Waveshare sample, this file just prints shapes and text to the display. It is quite an easy sketch to understand, especially with the Adafruit documentation.

The sketch finishes by printing some bizarre text on the display. The text is an excerpt from The Hitchhiker’s Guide to the Galaxy by Douglas Adams, and it’s a sample of Vogon poetry, which is considered to be the third-worst in the Galaxy!

Here is the hookup for the ESP32 and the GC9A01 display.  As with most ESP32 hookup diagrams, it is important to use the correct GPIO numbers instead of physical pins. The diagram shows the WROVER, so if you are using a different module you’ll need to consult its documentation to ensure that you hook it up properly.

The TFT_eSPI library is ideal for this, and several other, displays. You can install it through your Arduino IDE Library Manager, just search for “TFT_eSPI”.

There is a lot of demo code included with the library. Some of it is intended for other display sizes, but there are a few that you can use with your circular display.

To test out the display, you can use theColour_Test sketch, found inside the Test and Diagnostic menu item inside the library samples.  While this sketch was not made for this display, it is a good way to confirm that you have everything hooked up and configured properly.

A great demo code sample is theAnimated_dialsketch, which is found inside theSpritesmenu item.  This demonstration code will produce a “dial” indicator on the display, along with some simulated “data” (really just a random number generator).

In order to run this sketch, you’ll need to install another library. Install theTjpeg_DecoderLibrary from Library Manager. Once you do, the sketch will compile, and you can upload it to your ESP32.

One of my favorite sketches is the Animated Eyes sketch, which displays a pair of very convincing eyeballs that move. Although it will work on a single display, it is more effective if you use two.

The first thing we need to do is to hook up a second display. To do this, you connect every wire in parallel with the first display, except for the CS (chip select) line.

The Animated Eyes sketch can be found within the sample files for the TFT_eSPI library, under the “generic” folder.  Assuming that you have wired up the second GC9A01 display, you’ll want to use theAnimated_Eyes_2sketch.

The GC9A01 LCD module is a 1.28-inch round display that is useful for instrumentation and other similar projects. Today we will learn how to use this display with an Arduino Uno and an ESP32.

New functions have been added to draw smooth (antialiased) arcs, circles, and rounded rectangle outlines. New sketches are provided in the "Smooth Graphics" examples folder. Arcs can be drawn with or without anti-aliasing (which will then render faster). The arc ends can be straight or rounded. The arc drawing algorithm uses an optimised fixed point sqrt() function to improve performance on processors that do not have a hardware Floating Point Unit (e.g. RP2040). Here are two demo images, on the left smooth (anti-aliased) arcs with rounded ends, the image to the right is the same resolution (grabbed from the same 240x240 TFT) with the smoothing diasbled (no anti-aliasing):

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, I have created a branch with some bug fixes here. The library 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, the ESP8266 does not have sufficient RAM due to the glyph render complexity. 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:

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 only on ESP32 S3 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.

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 RP2040, STM32, ESP8266 and ESP32 types, other processors may be used but will use the slower generic Arduino interface calls. 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 (8 and 16 bit parallel) is only supported with the RP2040.

For other processors only SPI interface displays are supported and the slower Arduino SPI library functions are used by the library. Higher clock speed processors such as used for the Teensy 3.x and 4.x boards will still provide a very good performance with the generic Arduino SPI functions.

"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 (125MHz with overclocked RP2040, 55MHz with STM32 and 40MHz with ESP8266). The MHS-3.5 inch RPi ILI9486 based display is also supported, however the MHS ILI9341 based display of the same type does NOT work with this library.

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.

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 contains proportional fonts, different sizes can be enabled/disabled at compile time to optimise the use of FLASH memory. Anti-aliased (smooth) font files in vlw format stored in SPIFFS are supported. Any 16 bit Unicode character can be included and rendered, this means many language specific characters can be rendered to the screen.

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.

Anti-aliased (smooth) font files in "vlw" format are generated by the free Processing IDE using a sketch included in the library Tools folder. This sketch with the Processing IDE can be used to generate font files from your computer"s font set or any TrueType (.ttf) font, the font file can include any combination of 16 bit Unicode characters. This means Greek, Japanese and any other UCS-2 glyphs can be used. Character arrays and Strings in UTF-8 format are supported.

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 must make sure only one setup file is called. In the custom setup file I add the file path as a commented out first line that can be cut and pasted back into the upgraded User_Setup_Select.h file. The ../ at the start of the path means go up one directory level. Clearly you could use different file paths or directory names as long as it does not clash with another library or folder name.

M5StickC is a mini M5Stack, powered by ESP32. It is a portable, easy-to-use, open source, IoT development board. What it can do? This tiny block is able to realize your idea, enlighten your creativity, and help with your IoT prototyping in a very short time. It will take away a lot of pains from the development process.M5stickC is one of the core devices in M5Stack product series.

By default, this library setup will work for NodeMCU using a ILI9341 driver. But in our case, we are using ESP32, so some of the setups have to be changed.

In section 2, we need to select the suitable pinout for your MCU. The default setup is for NodeMCU 8266, so comment out those lines by adding two slash characters //. And uncommenting those lines for esp32.

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).

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.

The content is intended to be updated from time to time, I will add more details if I found new display or library update. You can also help me enrich the content by leaving comments below.

You can run various IoT projects prefectly without any display. But not all IoT project only feed data in single direction (IoT to server), some IoT also gather real time information from the server for displaying.

My previous instructables, ESP32 Photo Clock is am example, it download a current minute photo from the Internet, decode the JPEG photo and display it.

Many Arduino projects use monochrome display, one of the reason is the limited resources of a MCU. 320 pixels width, 240 pixels height and 8 bits color for each RGB color channel means 230 KB for each full screen picture. But normal Arduino (ATmega328) only have 32 KB flash and it is time consuming (over a second) to read data from SD card and draw it to the color display.

ESP32 have changed the game! It have much faster processing power (16 MHz vs 240 MHz dual core), much more RAM (2 KB vs over 200 KB) and much more flash (32 KB vs 4 MB), so it is capable to utilize more color and higher resolution image for displaying. At the same time it is capable to do some RAM hungry process such as Animated GIF, JPEG or PNG file decoding, it is a very important feature for displaying information gathered from the internet.

Color display have many type of interfaces: Serial Peripheral Interface (SPI), 6-bit, 8-bit, 16-bit, 18-bit and 24-bit parallel interfaces and also NeoPixel!

SPI dominate the hobby electronics market, most likely because of fewer wire required to connect. Most display in my drawer only have SPI pins breaking out, so this instructables focus on SPI display and a few 8-bit display.

NeoPixel matrix is a very special type of color display. If you are interested in NeoPixel matrix display, here are some of my instructables using it:

There are various color display for hobby electronics: LCD, IPS LCD, OLED with different resolutions and different driver chips. LCD can have higher image density but OLED have better viewable angle, IPS LCD can have both. OLED have more power efficient for each light up pixel but may have burn-in problems. Color OLED operate in 14 V, it means you need a dedicate step-up circuit, but it is not a problem if you simply use with a break-out board. LCD in most case can direct operate in 3.3 V, the same operating voltage as ESP32, so you can consider not use break out board to make a slimmer product.

Software support on the other side also influence your selection. You can develop ESP32 program with Arduino IDE or direct use ESP-IDF. But since ESP-IDF did not have too much display library and not much display hardware supported, so I will concentrate on Arduino display libraries only.

For the beginner, I think buying adafruit, or similar supportive vendor, hardware and using its Arduino library can have good seamless experience (though I have no budget to try it all). TFT_eSPI library have better performance but configuration require make changes in the library folder. Ucglib and UTFT-ESP run a little bit slow but it support many hardware and it is a popular library, you can find many Arduino projects using it. LovyanGFX library start appear at 2019, it support many dev device such as M5Stack, M5StickC, TTGO T-Watch, ODROID-GO, ESP-WROVER-KIT, WioTerminal and more. I am also writing a new library called Arduino_GFX since 2019.

OLED have a big advantage, the pixel only draw power if it lights up. On the other hand, LCD back light always draw full power even you are displaying a black screen. So OLED can help save some power for the project powered by a battery.

The initial code have some variation, the color order can be RGB or BGR and the y coordinate range also have a few pixels variation. Some library differential it by red, green or black tag but the tag color may not always help. The worst case is alter the tag option one by one until you can see a fine result. The above last picture is an example of using wrong tag option, you can find 3 pixels height noise bar on the top.

Thanks for the popularity of wearable gadget, I can find more small size IPS LCD in the market this year(2018). The above picture is an 0.96" 80x160 IPS color LCD using ST7735 driver chip. As you can see in the 3rd picture, you can treat it as a 128x160 color display in code but only the middle part is actually displaying. The 4th picture is the display without breakout board, it is thin, tiny and very fit for a wearable project!

SSD1283A is 1.6" 130x130 display, it claim only consume 0.1 in sleep mode and backlight turned off. In sleep mode the last drawn screen still readable under sufficient lighting.

ST7789 also a common driver chip in ESP32 community. One of the reason is ESP32 official development kit using it. As same as ILI9341, ST7789 also can drive 240x320 resolution.

This also the highest pixel density color display in my drawer. As same as normal LCD, it can direct operate in 3.3 V, so it is very good for making slim wearable device.

There are many display libraries that can support various hardware. I have picked 4 of most popular Arduino library for comparison:Adafruit GFX Family

The display speed is one of the most important thing we consider to select which library. I have chosen TFT_eSPI PDQ test for this comparison. I have made some effort to rewrite the PDQ test that can run in 4 libraries. All test will run with the same 2.8" ILI9341 LCD.

As I found TFT_eSPI is the most potential display library for ESP32 in this instructables, I have paid some effort to add support for all my display in hand. The newly added display support marked letter M in red at the above picture, here is my enhanced version:

Adafruit sell various display module in hobby electronics market and they also have very good support in software level. Their display libraries all built on a parent class called Adafruit_GFX, so I call it Adafruit GFX Family. This library generally support most Arduino hardware (also ESP32).

In Arduino Library Manager simply search "adafruit display", you can see all the family members. If you want to install it, say ILI9341, simply select "Adafruit ILI9341" and then click install. Remember also install its dependent library "Adafruit GFX Library".

This library method signature is very similar to Adafruit GFX, but it is tailor-made for ESP8266 or ESP32. I think the source code is optimised for ESP32, so the PDQ result is much faster than other libraries.

Note: The most difficult part using this library is you are required to configure this library before you can use it. The configuration file is located at the library folder, it should be "Arduino/libraries/TFT_eSPI/User_setup.h" under you own documents folder. It have many comments help you to do that, please follow the comments step by step to finish the configuration. Here is my User_setup.h for ILI9341:

ESP32 + ILI9341 can run at SPI speed 40 MHz, it require some code change at library folder. The above pictures are the fine tuned result. Here are the code change summary:

ST7735 and ILI9341 are the most popular display, this 2 are better option for the beginner. You may notice LCD have a big weakness, the viewable angle, some color lost outside the viewable angle and the screen become unreadable. If you have enough budget, OLED or IPS LCD have much better viewable angle.

In most case, we study how to use a code library by searching sample on the web. I have tried search four libraries keyword in Github, Adafruit is most popular and UTFT the second.

Only Adafruit GFX Family is fully configurable in user code level, other 3 libraries require some configuration in the library folder. And also Adafruit have very good portal, there are many detailed post teach you how to use their products.

ILI9341 should be most valuable display for the beginner. Adafruit GFX Library should be most easy to use for the beginner, and since TFT_eSPI have very similar method signature, it is very easy to switch to a faster library later on.

OLED require 14 V to light up the pixel so it is not easy to decouple the breakout board. On the other hand, LCD (also IPS LCD) usually operate in 3.3 V, as same as the ESP32. In most case, there are only the LED control circuit required between LCD and ESP32, i.e. a transistor and few resistors. So it relatively easy to make it.

If you read through the data sheet of the color display, you may find most of color display can support 18 bit color depth (6 bit for each RGB channel). 18 bit color depth can have a better image quality that 16 bit color depth (5 bit in red and blue channel, 6 bit for green channel). However, only Ucglib actually run at 18 bit color depth (262,144 colors), other 3 libraries all run at 16 bit color depth (65,536 colors). It is because 18 bit color depth actually require transfer 3 bytes (24 bit) of data for each pixel, it means 50% more data require to transfer and store in memory. It is one of the reason why Ucglib run slower, but it can have a better image quality.

Thank you very much for posting this detailed review of the color display option available for "Duino users. You have saved me hours, maybe days of time wandering the web looking for information.0

Great article! Very interested in round displays. There are available round displays based on st7687s (128 * 128) and st7789 (240 * 240), but I have not found any information on practical use.

Hello! Yes, I purchased this display from keyestudio, connected it to esp32 using this library from dfrobot. It is only necessary to consider that the pinout of the display connectors differs from dfrobot and keyestudio.

I"m wanting to connect a VGA camera, the sort you find as a little module on eBay with OVPxxxx chip, to a screen such as ILxxxx family, which appears to have direct VGA input. I think it will work if I connect the camera directly with no MCU, but I"d also like to add a cross-hair to the display (for a drill targetting system). I wonder is it possible to intercept the serial video data and change individual pixels in a streaming fashion, instead of loading a whole screen into memory, changing it and passing it on? I ask because it seems to me it would need a much less powerful MCU.0

Thank you so much for such a great article. I have been trying to choose the best library to use for a project that will use either a SSD1351 or a ST7735 both being 128x128. The key to my project is to be able to dump a frame buffer in to the display and then recalculate the next frame buffer. :)

Those 2 pins must be dedicated to the display, otherwise the display will get confused without the CS pin. One DAT/CLK to LCD and another DAT/CLK to I2C.

Hello! Thank"s for your instruction. I want to use your 8pin ili9486 320x480 spi display with one of your presented libraries and esp32. 1.) Could you please tell me the connections between the display and the esp32 and 2.) which numbers do I have to write into the line utft myglcd (ili9486,?,?,?,?)?

"Upper layer" main development board contains ESP32-PICO-D4 SiP, battery connector & charger circuit with LiPo charge status LEDs, Reset & pull-up IO0 buttons, and a green LED on GPIO4.

Clone of the SparkFun ESP32 Thing board. Compact ESP32 based development board with battery connector, and the typical development board component accoutrements.

The ESP32-LyraTD-MSC Audio-Mic HDK (hardware development kit) combines the ESP32-LyraTD-MSC ("audio-mic development board") with a secondary "top" board.

The ESP32 touch sensor development kit, ESP32-Sense Kit, is used for evaluating and developing ESP32 touch sensor system. ESP32-Sense Kit consists of one motherboard and multiple daughterboards. The motherboard contains a display unit, a main control unit and a debug unit. The daughterboards have touch electrodes in different combinations or shapes, such as linear slider, wheel slider, matrix buttons and spring buttons, depending on the application scenarios. Users can design and add their own daughterboards for special usage cases.

ESP-WROOM-32 based development board with SH1106 OLED display (128×64 pixels), RJ-45 Ethernet connector, CAN-bus connector, Micro USB connector, USB-to-UART bridge, LiPo battery connector and charging circuit.

ESP32 development board with ePaper display, TI PCM5102A DAC, ICS43434 MEMS Microphone, CP2102N USB-to-UART bridge, microSD card slot, and LiPo charger.