mcufriend.com lcd tft display quotation

This note introduces a low-cost Thin Film Transistor (TFT) display to enhance the operation and usefulness of Liquid Crystal Display(LCD) devices. TFT technology controls the pixel element on the glass surface thereby greatly reducing image blurring and improving viewing angles.

The test board chosen for this exercise is the Elegoo Arduino UNO board from the corresponding Super Starter Kit. The kit already has several simple numeric and text displays. The TFT display may perhaps provide better ways to interact in applications.

The controller for the illustrated model of the TFT display is SSD1297.This information is important because the display (owing to its low cost and high popularity) has many different manufacturers who may not leverage the same controller instruction set. The specification of the controller in the coding exercises is examined in the Appendix section of this note.

Some familiarity with the coordinate system for displays (i.e. top-left is0, 0) and the packing of RGB values into a 16-bit word (5 for R &B, 6 for G) makes the learning curve ramp at a faster pace.

Of course, the display can be mounted elsewhere and the pins connected to the Arduino directly or indirectly using, for example, a breadboard. Other components can then use the breadboard in lieu of a shield with custom connectors. Of course, without access to such anon-standard or readily available breadboard, it is impossible to illustrate this arrangement in this note.

The Examples folder for the library provides the starter files for the tests. If you are using a newer display you will need the updated libraries from the GitHub repository (see link in References below)and using the#definestatement to identify the display model.

The output from the diagnostic program, LCD_ID_reading.ino, is shown below:Read Registers on MCUFRIEND UNO shieldcontrollers either read as single 16-bite.g. the ID is at readReg(0)or as a sequence of 8-bit valuesin special locations (first is dummy)reg(0x0000) 97 97ID: ILI9320, ILI9325, ILI9335, ...reg(0x0004) 97 97 97 97Manufacturer IDreg(0x0009) 97 97 97 97 97Status Registerreg(0x000A) 97 97Get Power Modereg(0x000C) 97 97Get Pixel Formatreg(0x0061) 97 97RDID1 HX8347-Greg(0x0062) 97 97RDID2 HX8347-Greg(0x0063) 97 97RDID3 HX8347-Greg(0x0064) 97 97RDID1 HX8347-Areg(0x0065) 97 97RDID2 HX8347-Areg(0x0066) 97 97RDID3 HX8347-Areg(0x0067) 97 97RDID Himax HX8347-Areg(0x0070) 97 97Panel Himax HX8347-Areg(0x00A1) 97 97 97 97 97RD_DDB SSD1963reg(0x00B0) 97 97RGB Interface Signal Controlreg(0x00B4) 97 97Inversion Controlreg(0x00B6) 97 97 97 97 97Display Controlreg(0x00B7) 97 97Entry Mode Setreg(0x00BF) 97 97 97 97 97 97ILI9481, HX8357-Breg(0x00C0) 97 97 97 97 97 97 97 97 97Panel Controlreg(0x00C8) 97 97 97 97 97 97 97 97 97 97 97 97 97GAMMAreg(0x00CC) 97 97Panel Controlreg(0x00D0) 97 97 97Power Controlreg(0x00D2) 97 97 97 97 97NVM Readreg(0x00D3) 97 97 97 97ILI9341, ILI9488reg(0x00D4) 97 97 97 97Novatek IDreg(0x00DA) 97 97RDID1reg(0x00DB) 97 97RDID2reg(0x00DC) 97 97RDID3reg(0x00E0) 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97GAMMA-Preg(0x00E1) 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97 97GAMMA-Nreg(0x00EF) 97 97 97 97 97 97ILI9327reg(0x00F2) 97 97 97 97 97 97 97 97 97 97 97 97Adjust Control 2reg(0x00F6) 97 97 97 97Interface Control

The controller is referenced as SSD1297 with ID=0x9797. This display requires the use of the following statement in the code prior to the invocation of other header files for the display. Please review the header files for the equivalent#define SUPPORT_1289

Many thanks toDavidPrenticefor the display driver library and the guidance, support and advice during the tests for this display. I would have failed at the starting block without his generous assistance. He is an authority on the drivers for this class of displays.

Btw. I think that is what is all about! After the turn off sequence, the display must be turn off by shutting the power. That is what is in Figure 75 of the specs (LGDP4532 v0.12), "Turn the power supply off (Vcc, Vci, IOVcc)" after the power off sequence. So the display is perfectly fine, just needs additional hardware care to turn it off.

This post explains about how to display text on TFT lcd using arduino uno? TFT which is used in the tutorial is 2.4′ TFT by Mcufriend. It has ST7781 controller in it, Driver code is ST7783. This 2.4 inch TFT Lcd is arduino compatible. It can easily be mounted on an Arduino uno board. This TFT can be interfaced in 32,16 and 8 bit parallel mode. It also supports I2c Mode. In this tutorial i am going to interface it in 8-bit parallel mode with arduino uno.

Project code is below. I am not using any predefined library for displaying text on TFT lcd, I actually didn’t find any library that can properly display text on the TFT i have, all the libraries through which i have gone through were unable to initialize my lcd driver properly. So i decided to first read the driver of the TFT and then write my own code according to the driver supported commands. I first read the TFT Driver. To learn about how to check the TFT Lcd driver just go through this small tutorial.

After reading the driver of TFT i went through its datasheet. The TFT which i have is working with ST7781 controller, it’s a Chinese manufactured TFT by Mcufriend, their website says that the TFT is working on ILI9321 driver but its not. The information on ther website is misleading everyone, I have seen many posts on internet that talks about the Mcufriend TFT Lcd driver. So if you have a TFT and you are unable to find its driver than go through the above tutorial.

The TFT use in project can easily be mounted on any Arduino board. I mounted it on Arduino uno. You can also use any other Arduino board but for that you have to make changes in the code.

Changing the code is not a hard task if you understand the code written below. Coming to the Code. I first initialized the TFT Controlling pins LCD_RST, LCD_CS, LCD_RS, LCD_WR, LCD_RD. In the Setup function I made the Port-D and Port-B of Arduino Uno as output Port. Since the data pins of TFT is interfacing with Port-D and Port-B of Arduino so to write data and commands to TFT we have to declare Port-D and Port-B as output. Then the function InitializeTFT() is initializing the TFT.

In the Loop function i am filling TFT with colours. Colors are filled in Horizontal and vertical directions. According to the data sheet which says you can display text on TFT in eight directions.

The Code above will fill TFT with colors and the code below is displaying text “www.microcontroller-project.com” on TFT. Try to first understand the above code before moving to the code below. Above code is simply a method to fill the pixels of TFT. If you grabbed the process of filling TFT Pixels than you can display any text on lcd by manipulating the pixels.

Bought a cheap LCD form china (mcufriend, pictured below) and I cant understand which pin is which to use it with the SPI interface (starting to get worried that I can"t use it), I"ve figured out this much:

I bought four MCU Friend 3.5″ TFT shields.  And, unfortunately, they have spiraled me into a deep, dark place trying to figure out how to use them.  The the documentation consists of a sticker on the antistatic bag, a picture of the shield with a list of 5 different possible LCD drivers, a pinout, and a block of code that supposedly represents the startup code.  The unfortunate part is that none of these have been exactly right – they all have errors.  This article is a description of the journey to figuring out how to use them.

It also has a picture which says the LCD has one of several different controllers (and after digging in I know for a fact that two of mine were made by Raydium and are not on the list)

Next, I started down the path of trying to figure out what the controllers were by using register reads.  David Prentice (the guy who wrote/maintains the MCU Friend_kbv Arduino library) has an absolute ton of responses on the Arduino forum trying to help people figure out what their shield is.  He asks them to post the register report from his example program LCD_ID_readnew which is included as an example in the library.

When you look at these LCD controllers they all have some variant of “Read ID” which responds with 1-6 bytes.  The basic idea of this program is to look at what bytes are returned to try to identify the controller.  Here is an example of what I got when I ran the LCD_ID_readnew program on my shields:

The key thing to see in this output is the register 0x04 which says 54,80,66 which identifies this as a Raydium RM68140 LCD controller.  Here is a snapshot from the data sheet.

After digging some more, I decided that it is super ugly out there, as you find that there are a significant number of LCD controllers that are clones, copies, pirated etc… and that they all present themselves differently.  And, in hindsight I think that this is the reason that my ILI9341 from the previous article doesnt quite work correctly.

At this point I have spent a frightening amount of time figuring out how these screens work.  Although it has been a good learning experience, I have generally decided that using unknown displays from China with LCD drivers of questionable origin is not worth the pain of trying to sort out the interface.  Beyond that:

TFT displays are full color LCDs providing bright, vivid colors with the ability to show quick animations, complex graphics, and custom fonts with different touchscreen options. Available in industry standard sizes and resolutions. These displays come as standard, premium MVA, sunlight readable, or IPS display types with a variety of interface options including HDMI, SPI and LVDS. Our line of TFT modules include a custom PCB that support HDMI interface, audio support or HMI solutions with on-board FTDI Embedded Video Engine (EVE2).

Displaying a custom image or graphic on a LCD display is a very useful task as displays are now a premium way of providing feedback to users on any project. With this functionality, we can build projects that display our own logo, or display images that help users better understand a particular task the project is performing, providing an all-round improved User Experience (UX) for your Arduino or ESP8266 based project. Today’s tutorial will focus on how you can display graphics on most Arduino compatible displays.

The procedure described in this tutorial works with all color displays supported by Adafruit’s GFX library and also works for displays supported by the TFTLCD library from Adafruit with little modification. Some of the displays on which this procedure works include:

While these are the displays we have, and on which this tutorial was tested, we are confident it will work perfectly fine with most of the other Arduino compatible displays.

For each of the displays mentioned above, we have covered in past how to program and connect them to Arduino. You should check those tutorials, as they will give you the necessary background knowledge on how each of these displays works.

For this tutorial, we will use the 2.8″ ILI9325 TFT Display which offers a resolution of 320 x 340 pixels and we will display a bitmap image of a car.

As usual, each of the components listed above can be bought from the links attached to them. While having all of the displays listed above may be useful, you can use just one of them for this tutorial.

To demonstrate how things work, we will use the 2.8″ TFT Display. The 2.8″ TFT display comes as a shield which plugs directly into the Arduino UNO as shown in the image below.

Not all Arduino displays are available as shields, so when working with any of them, connect the display as you would when displaying text (we recommend following the detailed tutorial for the display type you use of the above list). This means no special connection is required to display graphics.

Before an image is displayed on any of the Arduino screens, it needs to be converted to a C compatible hex file and that can only happen when the image is in bitmap form. Thus, our first task is to create a bitmap version of the graphics to be displayed or convert the existing image to a bitmap file. There are several tools that can be used for creation/conversion of bitmap images including, Corel Draw and Paint.net, but for this tutorial, we will use the Paint.net.

The resolution of the graphics created should be smaller than the resolution of your display to ensure the graphics fit properly on the display. For this example, the resolution of the display is 320 x 340, thus the resolution of the graphics was set to195 x 146 pixels.

Image2Code is an easy-to-use, small Java utility to convert images into a byte array that can be used as a bitmap on displays that are compatible with the Adafruit-GFX or Adafruit TFTLCD (with little modification) library.

With this done, we are now ready to write the code. Do note that this procedure is the same for all kind of displays and all kind of graphics. Convert the graphics to a bitmap file and use the Img2code utility to convert it into a hex file which can then be used in your Arduino code.

To reduce the amount of code, and stress involved in displaying the graphics, we will use two wonderful libraries; The GFX library and the TFTLCD library from Adafruit.

The GFX library, among several other useful functions, has a function called drawBitmap(), which enables the display of a monochrome bitmap image on the display. This function allows the upload of monochrome only (single color) graphics, but this can be overcome by changing the color of the bitmap using some code.

The Adafruit libraries do not support all of the displays but there are several modifications of the libraries on the internet for more displays. If you are unable to find a modified version of the library suitable for your the display, all you need do is copy the code of the drawBitmap() function from the GFX library and paste it in the Arduino sketch for your project such that it becomes a user-defined function.

The first two are thex and y coordinates of a point on the screen where we want the image to be displayed. The next argument is the array in which the bitmap is loaded in our code, in this case, it will be the name of the car and the text array located in the graphics.c file. The next two arguments are the width and height of the bitmap in pixels, in other words, the resolution of the image. The last argument is the color of the bitmap, we can use any color we like. The bitmap data must be located in program memory since Arduino has a limited amount of RAM memory available.

As usual, we start writing the sketch by including the libraries required. For this procedure, we will use the TFTLCD library alone, since we are assuming you are using a display that is not supported by the GFX library.

Next, we specify the name of the graphics to be displayed; car and title. At this stage, you should have added the bit array for these two bitmaps in the graphics.c file and the file should be placed in the same folder as the Arduino sketch.

With that done, we proceed to the void loop function, under the loop function, we call the drawbitmap() function to display the car and the text bitmap using different colors.

The last section of the code is the drawBitmap function itself, as earlier mentioned, to use the drawbitmap() function with the Adafruit TFTLCD library, we need to copy the function’s code and paste into the Arduino sketch.

Plug in your screen as shown above. If you are using any other display, connect it as shown in the corresponding linked tutorial. With the schematics in place, connect the Arduino board to your PC and upload the code. Don’t forget the graphics file needs to be in the same folder as the Arduino sketch.

That’s it for this tutorial guys. The procedure is the same for all kinds of Arduino compatible displays. If you get stuck while trying to replicate this using any other display, feel free to reach out to me via the comment sections below.

Mine have a S6D0154 controller. The library was from "https://github.com/samuraijap/TFTLCD-Library". For Arduino UNO, you need to install both libraries attached, then replace the file "pin_magic.h" from the installation folder "libraries\TFTLCD-Library-master", with the "pin_magic.h" file attached here.