ili9486 tft display arduino library brands

Hello everyone to my new tutorial in which we are going to program arduino for tft lcd shield of 3.5" with ILI9486 driver, 8 bit. I found it important to write this tutorial as if we see we find tutorial for 1.44, 1.8, 2.0, 2.4, 2.8 inch shields however there are no or less tutorials available for 3.5" shield as its completely different from other smaller tft lcd shields -adafruit tft lcd library doesn"t even support ILI9486 driver in 3.5" tft lcd, it supports drivers of tft shields lesser then 3.5"

Go through the above link to know better, lets start with our tutorial however if we can"t use Adafruit_TFTLCD library which library will we use ?, there"s a simple answer to this that"s MCUFRIEND_kbv library which helps to use 3.5" tft lcd shield, if you see this library makes it much more easier to program arduino for tft lcd shield than adafruit as we have to simply create a tft object in MCUFRIEND_kbv library and then using that we can control the tft lcd shield however in Adafruit_TFTLCD library we will have to create the object and also define connections which makes it a very long task.

Once added, create the tft object using library name and a name for object, you can also define some color codes for text which we are going to type, using the define function and giving color code. This all is to be done before setup.#include#include#define BLACK 0x0000#define RED 0xF800#define WHITE 0xFFFFMCUFRIEND_kbv tft;

Its time to now start our tft lcd screen and change the background, this is to be done by using some simple functions by obtaining the tft ID and changing the background bytft.fillScreen("color_name");void}

Now we will be programming in loop for printing text on TFT LCD shield, for that we will be using a number of functions such as -tft.setCursor("x","y");x means the position from the x axis on screen and y means position from the y axis on screen of tft lcd shield.tft.setTextSize("number");number here refers to text size which take parameter as number you can give any number from 1 according to your requirements.tft.setTextColor("color");color here means to give the color name we had defined before setup, this makes the text color as whatever you give.tft.print("value");value is nothing but what you want to print, whatever you give as value must be in double quotes.void loop() {// put your main code here, to run repeatedly:tft.setCursor(0,0);tft.setTextSize(3);tft.setTextColor(WHITE);tft.print("my first project with tft -");tft.setCursor(0,70);tft.setTextSize(2);tft.setTextColor(RED);tft.print("welcome to the world of arduino and display , myself I love arduino and game programming very much. This is why I have my own youtube channel in which I share my arduino projects and games made by me , isn"t it amazing !");}

Graphics which we see in our phone is combination of square, rectangle, circle, triangle, lines. This is why here we will learning how to draw the following shapes.tft.drawRect(x,y,width,height,color);x means the position from the x axis of the screen, y means the position from y axis of the screen, width refers to set the width of rectangle, height refers to set the height of the rectangle and color means the color of rectangle you want it to be. You can use this same function by simply keeping the height and width same.tft.drawCircle(x,y,radius,color);x means the position from the x axis of the screen, y means the position from y axis of the screen, radius is a para to set the radius of circle and color means the color of circle you want it to be.tft.drawTriangle(x1,y1,x2,y2,x3,y3,color);x1, y1, x2 etc. are to set the position of triangle"s three points from which lines are drawn.tft.drawLine(x1,y1,x2,y2,color);x1 and y1 are to set point 1 from which line is made to point 2 which is set by x2 and y2.

I have shown we can draw text and shapes by which we can make various graphics, you can also refer to code given by me, one is for text and other is for graphics display.

The 3.5-inch TFT LCD Touch Display Shield for Arduino Uno is fully assembled, tested and ready to go. Simply plug it in and load up a library – you’ll have it running in under 10 minutes! Works best with any classic Arduino ATMEGA328 Board. So spice up your Arduino UNO project with a beautiful large display shield with a built-in microSD card connection. This TFT display is big (3.5″ diagonal) bright (4 white-LED backlights) and colourful (18-bit 262,000 different shades). The Display comes with 480×320 pixels with individual pixel control. It has way more resolution than a black and white 128×64 display.

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.

You must add the library and then upload the code. If it is the first time you run an Arduino board, don’t worry. Just follow these steps:Go to www.arduino.cc/en/Main/Software and download the software of your OS. Install the IDE software as instructed.

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().

First you should convert your image to hex code. Download the software from the following link. if you don’t want to change the settings of the software, you must invert the color of the image and make the image horizontally mirrored and rotate it 90 degrees counterclockwise. Now add it to the software and convert it. Open the exported file and copy the hex code to Arduino IDE. x and y are locations of the image. sx and sy are sizes of image. you can change the color of the image in the last input.

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.

In this template, We added a converted image to code and then used two black and white arcs to create the pointer of volumes.  Download the .h file and add it to the folder of the Arduino sketch.

In this template, We added a converted image and use the arc and print function to create this gauge.  Download the .h file and add it to folder of the Arduino sketch.

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.

Note: The following picture is the connection diagram of the 2.8-inch TFT screen and Arduino uno, but this product is connected in exactly the same way.

If the Arduino board has an ICSP interface, set the SPI Config switch on the display module to the ICSP direction (by default) (the company"s Arduino UNO motherboard has an ICSP interface, just plug it in directly.).

This product uses the same LCD control chip and touch panel control chip as the 3.5-inch TFT screen of the same series of our company, so the code is completely compatible. The following takes 3.5-inch TFT as an example to introduce.

LCD_Show can display colorful patterns with different shapes and times. LCD_ShowBMP is for displaying the picture in BMP, and LCD_Touch is for using the touching function.

The display controller used in this product is ILI9486, and we need to initialize the controller through the SPI communication protocol, and the initialization functions are written in LCD_Driver.cpp.

The function functions related to the screen display are written in LCD_GUI.cpp. The function of each function and the parameters passed are explained in the source code. You can call it directly when you need to use it.

Before using LCD_ShowBMP to display pictures, first copy the pictures in the PIC folder in the data to the root directory of the SD card (you should understand that in the root directory, that is to save the pictures directly to the SD card, do not put them in any subfolders folder.).

Here is an explanation. This demo shows that the BMP picture first reads the picture data in the BMP format in the SD card through the SPI protocol, and then displays the data as an image.

These functions are all written in LCD_Bmp.cpp. In fact, the image data in BMP format with a specific file name is read from the SD card, and then the display function written by us is called to re-express the data as an image.

If you need characters in different sizes and fonts, you can generate the font library you want according to the font extraction software provided in the Resource.

In fact, you can also use Image2Lcd image modulo software to convert images of different sizes and formats into array data, and then use the functions we wrote to display them.

Note: The following picture is the connection diagram of the 2.8-inch TFT screen and XNUCLEO-F103RB, but this product is connected in exactly the same way.

The demos are developed based on the HAL library. Download the program, find the STM32 program file directory, and open STM32\XNUCLEO-F103RB\lcd4in-demo\MDK-ARM\ lcd4in-demo.uvprojx.

This product uses the same LCD control chip and touch panel control chip as the 3.5-inch TFT screen of the same series of our company, so the code is completely compatible. The following takes 3.5-inch TFT as an example to introduce.

After running the demo, it displays some characters and patterns at first, then displays four pictures, and finally displays the touch sketchpad function. Actually, three projects in the Arduino platform code are integrated in the main function, we place the three main functions in sequence and place TP_DrawBoard(); in an infinite loop to achieve the above functions.

Before using LCD_ShowBMP to display pictures, copy the pictures in the PIC folder in the data to the root directory of the SD card, and then insert the SD card into the SD card slot on the back of the screen to start the download program verification.

If you need characters of different sizes and fonts, you can generate the font library you want according to the font extraction software provided in the data.

In fact, you can also use Image2Lcd image modulo software to convert images of different sizes and formats into array data, and then use the functions we wrote to display them.

I bought online this LCD Touchscreen Kuman SC3A-NEW-UK. It uses ILI9486 drivers, but it didn"t include any instructions manual, and kumantech.com seems to be devoid of complete technical documentation about SC3A-NEW-UK model.

Just in case it wasn"t noticable: I am trying to make a "Hello World" for my SC3A-NEW-UK"s LCD Touchscreen from an Arduino UNO board. In other words: just print "Hello World" to see if it works.

To see if I can use it, I tried downloading a whole ZIP from this Github project, and inside the Arduino IDE, I tried adding the downloaded library using the option "Include .ZIP library". If I copy-paste the code example provided within README.md (the following) and compile:

...and I have no idea what this FS library is supposed to be, so I don"t think I can use that Github project at all... I am tempted to assume that Github"s project is dead.

This compiled in Arduino IDE, no problem, but I still don"t know if it will work well with my screen. I am also confused about initialization of the TFT object and how would I have to wire the LCD screen to the Arduino depending on this initialization:

...specially having in mind that I don"t know how am I supposed to wire the LCD screen to the Arduino yet. It seems the LCD pins have been designed to fit in directly to the Arduino board without thinking too much about it (like the shape is the same), but that would make the screen getting all the Arduino UNO"s pins for itself, so I don"t think so...

...so, powering the screen shouldn"t be a big deal, but, how am I supposed to connect everything else? I am completely misguided about how am I supposed to interact with the screen from Arduino code... what is RS pin for? Should I use 4-bit or 8-bit mode? (I think 4-bit would imply connecting 4 digital pins for the screen, and 8-bit the whole 8 pins from screen to the Arduino UNO board)? Should I use LCD_RD and LCD_WR? Well you have a picture of my confusion.

Searching for documentation in the internet only leads me to partial examples. Not even using the model Ref ( SC3A-NEW-UK ) or the driver"s ref ( ILI9486 ) as keywords for searching in Google leads me to clear documentation about howto wire stuff, or which specific libraries should I use...

Even though I know how to control Input/Output in Arduino code to interact with analog/digital input and output pins at will with C++ in Arduino code (but even so, I think I"m still an Arduino n00b), this LCD screen"s physical interface is very confusing to me...

PD: I have read somewhere that this SC3A-NEW-UK Touchscreen is made to shield Arduino MEGA boards (by fitting the PINs directly into it), but mine is an Arduino UNO Board! (perhaps I shouldn"t have bought This LCD model, then?)... but I have sets of wires, pinboards and stuff... I don"t want to give up the idea of harnessing this LCD screen using an Arduino UNO. I don"t care about shielding feature, I just want to wire it and make it work. I will figure out how to shield electronics later on.

Based on VE7JRO"s answer, I managed to map the connections by seeing where the connections would go if I just fit the connections shielding the Arduino UNO, the way VE7JRO suggested:

The bad thing about this layout is that it consumes almost all the Arduino pins, so I would not be able to attach additional circuits. However, perhaps I should not be worrying about earning connections yet, before testing the screen.

There are 22 test sketches that come with the MCUFRIEND_kbv library. One of them scans your display and outputs configuration information (sorry, it"s been a while since I tested my screen). Another sketch will draw little boxes in each corner and sides. This is used to get the x y coordinates of the edges of your particular screen (it might be called TouchScreen_Calibr_native.ino).

Note: The following picture is the connection diagram of the 2.8-inch TFT screen and Arduino uno, but this product is connected in exactly the same way.

If the Arduino board has an ICSP interface, set the SPI Config switch on the display module to the ICSP direction (default) (the company"s Arduino UNO motherboard has an ICSP interface, just plug it in directly).

Unzip the compressed package, and then open the folder, then open the Arduino folder, you can see three project folders LCD_Show, LCD_ShowBMP, LCD_Touch.

LCD_Show is used to display some patterns of different color shapes and time, LCD_ShowBMP is used to display pictures in BMP format, LCD_Touch is used to use touch function.

The display controller used in this product is ILI9486, we need to initialize the controller through the SPI communication protocol, and the initialization functions are written in LCD_Driver.cpp

The function functions related to the screen display are written in LCD_GUI.cpp. The function of each function and the parameters passed are explained in the source code. You can call it directly when you need to use it.

Before using LCD_ShowBMP to display pictures, first copy the pictures in the PIC folder in the data to the root directory of the SD card (you should understand that in the root directory, that is to save the pictures directly to the SD card, do not put them in any subfolders folder).

Here is a little explanation. This routine shows that the BMP picture first reads the picture data in the BMP format in the SD card through the SPI protocol, and then displays the data as an image.

These functions are all written in LCD_Bmp.cpp. In fact, the image data in BMP format with a specific file name is read from the SD card, and then the display function written by us is called to re-express the data as an image.

If you need characters of different sizes and fonts, you can generate the font library you want according to the font extraction software provided in the data.

In fact, you can also use Image2Lcd image modulo software to convert images of different sizes and formats into array data, and then use the functions we wrote to display them.

Note: The following picture is the connection diagram of the 2.8-inch TFT screen and XNUCLEO-F103RB, but this product is connected in exactly the same way.

The demos are developed based on the HAL library. Download the program, find the STM32 program file directory, open STM32\XNUCLEO-F103RB\lcd3in5-demo\MDK-ARM\ lcd3in5-demo.uvprojx

After this demo runs, it first displays some characters and patterns, then displays four pictures, and finally displays the touch drawing board function. In fact, it is the integration of the three projects of the Arduino platform code into the main function. The functions are placed in order and TP_DrawBoard(); is placed in an infinite loop to achieve the above functions.

Before using LCD_ShowBMP to display pictures, first copy the pictures in the PIC folder in the data to the root directory of the SD card, and then insert the SD card into the SD card slot on the back of the screen to start the download program verification.

If you need characters of different sizes and fonts, you can generate the font library you want according to the font extraction software provided in the data

In fact, you can also use Image2Lcd image modulo software to convert images of different sizes and formats into array data, and then use the functions we wrote to display them.

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In my searches for an appropriate board I realized that Arduino compatible 2.4 inch touch TFTs with SPI interface have almost the same price as 3.5 inch 480×320 touch TFT display modules for RPi. I decided to buy one of these.

Also, the nature of the ILI9341 SPI commands e.g to set individual pixels by sending address then value, is very inefficient, especially as the default Adafruit library does not buffer these transfers into one larger SPI transfer.

Most TFT controllers can be configured for 8-bit SPI. The minimum write-cycle is marginally faster with 8080 parallel-interface. The minimum read-cycle is faster with SPI than parallel. OTOH, SPI is easily controlled with DMA.

As far as I know, RPi drives the display as “frame buffer”. It means, it has a complete image buffer in RAM and writes it as a whole frame always all over again with high speed to the display. So it does not need to change the window coordinates, no switch between command and data select. That’s why it can really work with DMA.

I have a custom made PCB I am using for these tests, which has a maple mini on one side and the ILI9341 display on the other, so that the wires (pcb tracks) are quite short ( approx 3 cm)

Using double buffering would allow the best use of DMA ( if we had a completion callback) as calculation of line, pixel and text drawing must be taking almost as much time as the SPI data transfer to the display

I was having a look at those numbers, and I’m surprised too at getting the same speed with DMA and without, but I also noticed you can’t run the display at the max SPI speed.

A while back when porting the sd-fat library I did some tests with and without DMA at slower SPI speeds, and noticed pretty much the same, up to a certain point DMA was not faster than normal.

If I remember right, I did some test with the ILI library where it would only use DMA if the line to draw was longer than N pixels, and use the normal transfer for smaller lines, and found the minimum number of pixels for DMA to make a difference. Still the gains over using DMA all the time at full speed were not significant, but did show that normal transfers were faster if under a number of bytes.

Victor, the tests ran at 36 MHz, but the display was partially corrupted. Before any optimization, the corruption was not that significant that after. If I speed-optimize the register writing, than i have more problems, randomly.

It looks a lot like they may be salvaged from old mobile phones, I had similar issues with the Nokia 5110 displays from eBay as a lot of them are not actually “new” (as advertised), they are salvaged and are often not even cleaned so were covered in whatever grime was in the mobile phone form years of use

Your comparison makes only sense if you compare same graphicstest software running on the same controller board (MM or blue pill) controlling same display controller (ILI9341?), driving same display resolution (320×240) in two different modes (parallel and serial at maximum possible speed).

stevestrong wrote:If you look on the scope screenshot (second blue/cyan block), you will observe that the SPI stream is continuous, no need for the controller to generate extra WR strobe between consecutive pixel data. This is managed by the hardware serial->parallel circuit on the display board.

This would provide a “sprite” transfer capability, cut out from a single source containing image and transferred through DMA to the display at the desired destination position. With little modifications, this could be used for fixed/variable font rendering too.

The ILI9486 specifies a WR cycle time of 50 ns min. (twc in datasheet, page 212), thus you are limited to 20 MHz on the 8080 interface side. The limit will be the HCT chips at the given VCC.

From fbtft sources, the RPi looks like it is driving this display @ 32 MHz, but this is using a full continuously refreshed frame buffer, so a glitch won’t be as noticeable as it will be redrawn on next frame anyway.

That’s interesting! I wonder which other ILI controllers have the same. That could make for really fast display drivers even with small buffers, and minimal cpu usage.

Just had a look at the ILI9341 datasheet, and supports a mode without D/C line, I guess there is some track cutting and soldering involved to reconfigure the display. Looks like the serial mode without DC line in the ILI9341 is serial 9bit, which complicates things in other ways

Yes, because of this, fast TFT screen circuits are using 8 or 16-bit parallel modes, since the controller built-in 3 or 4-wire SPI modes are getting roughly the same toggling speed, you get transfer performance divided by 8 or 16.

And although the RaspPi is driving the SPI @ 32 MHz which is above the guaranteed maximum frequency, it is still in the typical achievable ones, and as again the Pi is using a full frame buffer with continuous refresh, a glitch will get unnoticed, whereas the way the Arduino TFT library uses it is completely different, and pushing the transfer frequency to the limits will result in corrupted displays (if in data mode) or may hang the controller (if in register mode).

So my first guess is that Bodmer’s library is using the SPI library. And the SPI library limits SCK frequency to 40MHz. Edit. Bodmer’s User_Setup.h file specifies maximum 40MHz for SCK

The AVR SPI peripheral always has “gaps”. The AVR USART_MSPI peripheral can achieve full speed with no gaps. Of course you need a good Arduino SPI library to get the best out of the hardware.

The current SPI lib of Arduino_STM32 is already “gap-less” in non-DMA mode. That’s why all graphic test (except one) without DMA performs equal or better than with DMA, due to lacking DMA overhead.

I cannot see how any RPi would work correctly with this display at 40MHz, without any HW hacks. I saw blogs where rather 16MHz was suggested to be used, this sounds a lot more realistic. Also, there are several versions of such boards, maybe there are others with better characteristics/controllers.

Otherwise I see myself forced to remove the HC chips from the display board and drive the display with 16 bits parallel directly from BP (using PB0..15).

An “unreadable” display does not really interest me. However, it would be interesting to see just how fast your shift registers will work. After all, the 16-bit parallel could be driven up to 10x faster.

David, my original intention was just to have one display which is SPI driven. I have already one 240×320 display which is 8 bit parallel driven, and, of course, is much faster than this one. Here, I am limited by the serial->parallel converter.

Sorry. tDST is the data setup time before the active edge of /WR in the 8080 parallel interface. (ST7789 nomenclature. The ILI9486 datasheet might use a different acronym)

As far as I can see, a stock HC4040 is going to produce the WR signal before the HC4094 has loaded the shift register. i.e. it will be wrong for the ILI9486 and also wrong for the HC4094 to latch the shift register.

Still, there is one clock period delay at 36MHz between WR and data. That means, the color data is sampled as being is shifted one bit left. For example, if I want a red color (0x8000), the display controller will get 0x0001 sampled because of this one clock period propagation delay of WR edge relative to the parallel shifted data.

The chip works >150MHz internally, when routed you can mess with counters, shift registers and whatever logic you want at 80-90Mhz sure. The logic guys need is about 10 lines of verilog, or, with schematic capture the same schematics as above, as the library includes dozens components like those the guys use now for the tft (almost all ttl/cmos standard chips people mess with).

The trick is when you want to change something in the schematics – wiring or add a component or invert a signal, or fully change your design, you do it on the screen and then just flash – the same process as with arduino. The XC9536XL family has got flash memory for the wiring, programmble via jtag.The dev cycle is about 1-2minutes to change and run. And the chip is 100% routable so you can connect your tft to whatever pins you want – it always fits your new design/schematics to existing pin layout on the pcb (or in other words – your design can be always routed to any i/o pin setup you want).

Here is a 32bit freqmeter/periodmeter/counter in an XC9572XL I did 5y back for arduino forum as an example. It includes 2x16bit counters and 2x16bit shift registers and some logic (arduino had read the freq measured off the chip serially, only 7 pins used). The ring oscillator (3 invertors in loop) there did 150MHz freq.

I am still thinking where should the SPI initialization take place: outside the ILI9486 driver, in setup phase, before or within the driver begin() function?

I am still thinking where should the SPI initialization take place: outside the ILI9486 driver, in setup phase, before or within the driver begin() function?

Compiling the code from github produces some errors (not a problem), but one of them is the following – which is an apparent mismatch with SPI.cpp in hardware\Arduino_STM32\STM32F1\libraries\SPI\src.

The core of the issue (apart from my mis-paste from the core SPI library) seems to be that I was using the SPI library from Roger’s master repo, rather than Steve’s amended one.

I have used the SPI example in the STM32 library to test the SPI communication and the display responds always with the pattern 0x55, does it mean the communication is OK? I have disconnected it and I have got 0xFF!!! Looked fine to me!!

Well! Afterwards I could run the ILI9486 example program and got the run times statistic quite similar to the one in beginning of this post (see below!)

The problem is, that the display is just flashing white synchronously to the test sequences. After doing some debugging with Atollic , I could not detect any error.

I have followed all the hints above, but I could not run any demo on this display. The device I have bought looks exactly the same as yours at the beginning of this post. I have tried your example with no positive results. Obviously there is a serial parallel converter on the board, that why it is a write only device. I have tried ILI9481 and ILI9486 . If the controller is not ILI9486, what might it be?

It looks as if your display was made by WaveShare. So there is probably a schematic. So it should be easy to guess how the hardware needs to be driven.

Most 320×480 controllers are MIPI compliant. And probably start up by themselves. Just Reset, Display Off, Wake up, Display On. (with some pauses)

Finally I have got it done! I have found out the right initialisation sequence. The SPI frequency is crucial. The display works only in the range between 12MHz and 32MHz only. Any frequency out of this range lead to white flashing on the screen!

Hi. After spending a lot of time and seeing that the pin connection was correct, I decided to change the 5v power supply of the display and then the sketch of REG_ID showed that “reg (0x0000) 45 35” (though the remaining registers were all like 00 00).

There are several versions of Adafruit_TFTLCD library that have been hacked for an LGDP4535. There are probably some original ones too. As far as I know, they will only run on a Uno or Mega.

Anyway, I have one of these generic 3.5inch RPi LCDs. The above library works perfectly for running the LCD. The XPT_2046 library also works perfectly for driving the touch panel. BUT the two do not work together. Display calls break the touch panel, and vice-versa.

Did you enabled DMA? With DMA I have some artefacts with the graphic tests (not only with this display) It’s on my todo list to investigate the problem (maybe too much speed for the controller).

I do not own/use diff tools, because I don’t need them regularly (I just use notepad++ with the compare plugin on windows or XCode on OSX for such things (private)). It’s always better to post the whole code/library as *.zip or *.rar file as Attachments otherwise many people will cry “How to use this?” -especially under windows (there is no “patch” without further installing something)

The teensy library is MUCH slower – maybe the errors caused by to high speed (SPI or low level pin manipulations) – It should be not to difficult to find the problem as we have two – almost same – libraries