stm32f103 tft lcd library brands

The LCD I am using is a 2.8″ TFT LCD with SPI communication. I also have another 16-bit Parallel TFT LCD but it will be another story for another time. For this post, let’s focus on how to display what you want on the 2.8″ LCD. You can find all details about this LCD from this page:http://www.lcdwiki.com/2.8inch_SPI_Module_ILI9341_SKU:MSP2807

First thing first, this LCD use SPI as the main communication protocol with your MCU. For STM32 users, HAL Library has already implemented this protocol which makes this project easier for us. But, a little knowledge about this protocol does not hurt anyone. SPI is short for Serial Peripheral Interface which, aside from two data lines, also has a clock line and select lines to choose between devices you want to communicate with.

This LCD uses ILI9341 as a single-chip SOC driver for a display with a resolution of 240×320. More details can be found in the official document of ILI9341. But the most important thing is that we have to establish astart sequencein order for this LCD to work. The “start sequence” includes many other sequences which are also defined in the datasheet. Each sequence starts when you send a command to ILI9341 and then some parameters to follow up. This sequence is applied for all communication between MCU and ILI9341.

For this project, I recommend using theSystem Workbench for STM32for coding and building the code. After installing and open the program, go to the source code you have just downloaded and double click the.cprojectfile. It will automatically be open in your IDE. Then build the program by right click on the folder you just open (TFTLCD) and chooseBuild Project. Wait for it to finish and upload it to the board by right clicking the folder, choose Run As and then clickAc6 STM32C/C++ Application. And that’s it for running the example.

The most important library for this project is obviously the ILI9341_Driver. This driver is built from the provided source code in the lcdwiki.com page. I only choose the part that we need to use the most in many applications like writing string, displaying image and drawing symbols. Another library from the wiki page is the TOUCH library. Most of the libraries I got from the Internet were not working properly due to some adjustments to the original one.

To draw symbols or even display images, we need a “byte array” of that image or symbol. As an illustration, to display an image from a game called Transistor, I have a “byte array” of that image stored in a file named transistor.h. You can find this file in the link below. Then, I draw each pixel from the image to the LCD by adding the code in the Display_Picture() function in the Display folder.void Display_Picture()

Cross-platform Has no external dependencies and can be compiled for any vendor"s any MCU or MPU, and (RT)OS to drive ePaper, OLED or TFT displays, or even monitors.

I am particularly fond of the SPI interface because it uses a minimum number of I/O pins. This means that since even a minimal Arduino (one based on an ATmega328) can drive a low-cost TFT with I/O left for other tasks, the cost may be kept down. Nowadays, it is realistic to implement a basic Arduino with a 2.2″ TFT for less than 10€. An ATmega328 with an Arduino bootloader goes for 1,50€ on Ebay, a 2.2″ SPI TFT goes for about 3,50€, so “vintage” character LCDs are definitely on their way out.

Obviously, you need the TFT display itself. I don’t care where you buy it from – you may get it from Adafruit or SparkFun or iTead or any one of the “big name” shops or you may get it from Ebay (a.k.a. “China”). In my experience, it doesn’t really matter as long as you know what you are purchasing. For example, on Ebay when you search for 2.4″ SPI TFT LCD you will come across this:

They are essentially the same TFTs, but the first one is ~1€ cheaper than the second one. The difference is the PCB that is included. Do not underestimate this PCB. If you go for the plain TFT you will have to solder it to a suitable PCB like this one:

But let’s backtrack just a bit. How does one select a TFT? Surely, one would think that size and resolution are the most important factors. I say sure, as long as you have the software part covered. In order to actually show stuff on a TFT you need an appropriate library. You should not take for granted that such a library indeed exists for that gorgeous hi-res IPS TFT that you found for 10€ on Ebay. Many sellers on Ebay just write the word “arduino” on the TFT’s description without giving it much serious thought. Plus you should expect zero (0) support from most Ebay sellers. Most of them can’t and won’t help you if you run into trouble with your code.

So, you should always do a little research. Google is your friend. A good start is Karlsen Henning’s UTFT library. Being billed as a Universal TFT Library it does indeed support a large number of TFT controllers. If your display’s controller is included in UTFT’s compatibility list, you are somewhat covered. I say somewhat because UTFT is not always the best choice since it has a pretty heavy footprint. It will consume the better part of an ATmega328’s flash memory capacity. Fortunately, there are other libraries out there. I will go into more detail later on.

So, you got a TFT and are faced with the task of hooking it up to the Arduino. Relax, it’s simple. You only need to connect 4 or 5 wires, plus power and GND. Let’s start with the basics.

1) Power (Vcc). Most displays need 3.3V to function. This is a requirement of the TFT panel itself as well as of the driver IC that is always part of the assembly (it is an embedded part – you can not really see it). But as you probably know, most Arduinos run on 5V. Display manufacturers that make products for Arduino of course know that and usually include an on-board regulator that takes 5V as input and gives the necessary 3.3V. In most cases there is a selector on the PCB (jumper, solder bridge, or something) that lets you configure the board for 5 or 3.3 volt operation. Look out for that.

2) LED power. This pin controls the backlight of the TFT panel. It consists of a number of LEDs, depending on the size of the LCD panel. Bigger panel means more LEDs and thus more power consumption. It is usually connected to GND or to 5V/3.3V. Some times a current limiting resistor is also necessary. Other times the resistor is built-in and so is a mosfet that allows you to adjust the LED backlight’s brightness by connecting it to a pin that supports PWM (some of the more expensive TFTs support this). In any case, read the manual. You may come across a Chinese TFT that you had to have but then noticed that it has sparse if any documentation. If this happens, play it safe by connecting the LED pin to GND through a resistor (a few hundred ohms is usually a good starting point). If it lights, it means that the polarity is OK. If it does not, try applying 5 or 3.3V to it (through the resistor). If it lights but is too dim, use a smaller resistor. Usually each LED draws about 10-15mA, so if you know how many LEDs your TFT uses you can estimate its power draw and thus select a proper resistor.

A special note here: Signalling is usually done at 3.3V unless the TFT’s manufacturer has implemented some kind of level shifting on board the PCB. This level shifting may be done by an IC (best case), or a bunch of transistors and resistors (fair enough..) or just 1.2K resistors (a bit of a kludge, but it usually works). It is important to be careful not to send 5V into a TFT that only supports 3.3V logic because in that case you will most likely damage the TFT.

At this point you need to take a break from the hardware and consider the software, since your choice of library will dictate the particulars of the next step, which is the connection of the signal wires to the Arduino.

Ugly (blocky) fonts if you scale them to a non-native size. This is being fixed by 3rd party code that now supports a small number of proportional fonts but is nowhere near as versatile as UTFT’s code.

Depending on your choice of library, you may need to use the hardware SPI pins for CLK and MOSI or you may be free to use any pins you like. It really just depends on the library.

You may notice that most libraries say that you can just connect the TFT Reset pin to the Arduino Reset Pin. If you do that, you should put 0 as the reset pin.

According to my experence for another 2.2" LCD display with D/C Pin, I am using CD4050BE to convert the UNO pin 5v to 3.3v to fit to the TFT signal standard.

There are a few common TFT display drivers on the electronics hobbyist market, and a handful of libraries that work with them. TFT displays are high resolution and full color, unlike the OLED or ePaper displays mentioned in this repository. Most libraries for color TFT displays implement the usual 24-bit RGB color space, where 0xFF0000 is red, 0x00FF00 is green, and 0x0000FF is blue.

TFT displays can be slow to update. Therefore, it’s sometimes usefil to draw only part of the display at once. Adafruits GFX library includes a Canvas class, which lets you update elements offscreen and then draw them. It doesn’t speed up the display, but it can simplify drawing a subset of the screen. See this example to see it in use. Other libraries don’t include a canvas, but you can draw a filled rectangle over part of the screen and then draw on top of it, as shown in this example for the ILI9225.

Most TFT displays tend to have an SPI interface, with some extra pins, as explained on the main page of this repo. Some displays, like MakerFocus’ 1.3” TFT, do not implement the CS pin. For this board and others like it, initializing them with SPI_MODE3 works.

All of the displays listed below have been tested with the Adafruit_ST7735/ST7789 libraries and the Adafruit_GFX library, with the modifications mentioned below.

MakerFocus 1.3” LCD Display, no MicroSD, Amazon link - This display does not have a CS pin, so it can’t be used with other SPI devices at the same time. It works with the Adafruit_ST7789 library, but you have to change the init() function to include the SPI mode like so:

There’s no standard library for TFT screens, unfortunately. Vendors tend to support the displays they make in their own breakout boards, and not others. As with other types of displays, a well-supported library like the Adafruit libraries makes the display worth more, but limits you to the types of displays that vendor offers. Display manufacturers like Ilitek and Sitronix do not appear to release their own libraries for their displays.

The Adafruit_ST7735/7789 library and Adafruit_GFX library works well with some of the Sitronix boards above. It does not support the DFRobot ST7867S board, however.

The DFRobot_ST7687S library has slow refresh rate on the ST7687S board. It’s unclear whether the issue is the library or the board, however. I have yet to find another library to use with this display, though there are a couple other vendors for the board itself on Amazon. Unfortunately the u8g2 library doesn’t support this display, though it does support many of the Sitronix boards.

The TFT_22_ILI9225 library works with this display, and its methods are well documented. Its graphics API is different than some of the other graphics libraries, and doesn’t implement the Printable API, so you can’t use commands like print() and println() with it. It has its own drawText() method instead, which takes an Arduino String object. It comes with a few built-in fonts, and includes many of the Adafruit GFX fonts, and you can generate your own fonts using the The squix.ch custom font generator. Set the settings to