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.

Next is the distance sensor button. First we need to set the color and then using the fillRoundRect() function we will draw the rounded rectangle. Then we will set the color back to white and using the drawRoundRect() function we will draw another rounded rectangle on top of the previous one, but this one will be without a fill so the overall appearance of the button looks like it has a frame. On top of the button we will print the text using the big font and the same background color as the fill of the button. The same procedure goes for the two other buttons.

In this tutorial, you will learn how to use and set up 2.4″ Touch LCD Shield for Arduino. First, you’ll see some general information about this shield. And after learning how to set the shield up, you’ll see 3 practical projects.

The role of screens in electronic projects is very important. Screens can be of very simple types such as 7 Segment or character LCDs or more advanced models like OLEDs and TFT LCDs.

One of the most important features of this LCD is including a touch panel. If you are about to use the LCD, you need to know the coordinates of the point you touch. To do so, you should upload the following code on your Arduino board and open the serial monitor. Then touch your desired location and write the coordinates displayed on the serial monitor. You can use this coordination in any other project./*TFT LCD - TFT Touch CoordinateBased on Librery Examplemodified on 21 Feb 2019by Saeed Hosseinihttps://electropeak.com/learn/*/#include #include "TouchScreen.h"#define YP A2#define XM A3#define YM 8#define XP 9// For better pressure precision, we need to know the resistance// between X+ and X- Use any multimeter to read it// For the one we"re using, its 300 ohms across the X plateTouchScreen ts = TouchScreen(XP, YP, XM, YM, 300);void setup(void) {Serial.begin(9600);}void loop(void) {TSPoint p = ts.getPoint();if (p.z > ts.pressureThreshhold) {Serial.print("X = "); Serial.print(p.x);Serial.print("\tY = "); Serial.print(p.y);Serial.print("\tPressure = "); Serial.println(p.z);}delay(100);}

Displaying Text and Shapes on Arduino 2.4 LCD/*TFT LCD - TFT Simple drivingmodified on 21 Feb 2019by Saeed Hosseinihttps://electropeak.com/learn/*/#include #include #define LCD_CS A3#define LCD_CD A2#define LCD_WR A1#define LCD_RD A0#define LCD_RESET A4#define BLACK 0x0000#define BLUE 0x001F#define RED 0xF800#define GREEN 0x07E0#define CYAN 0x07FF#define MAGENTA 0xF81F#define YELLOW 0xFFE0#define WHITE 0xFFFF#define ORANGE 0xFD20#define GREENYELLOW 0xAFE5#define NAVY 0x000F#define DARKGREEN 0x03E0#define DARKCYAN 0x03EF#define MAROON 0x7800#define PURPLE 0x780F#define OLIVE 0x7BE0#define LIGHTGREY 0xC618#define DARKGREY 0x7BEFAdafruit_TFTLCD tft(LCD_CS, LCD_CD, LCD_WR, LCD_RD, LCD_RESET);void setup() {Serial.begin(9600);Serial.println(F("TFT LCD test"));#ifdef USE_ADAFRUIT_SHIELD_PINOUTSerial.println(F("Using Adafruit 2.4\" TFT Arduino Shield Pinout"));#elseSerial.println(F("Using Adafruit 2.4\" TFT Breakout Board Pinout"));#endifSerial.print("TFT size is ");Serial.print(tft.width());Serial.print("x");Serial.println(tft.height());tft.reset();uint16_t identifier = tft.readID();if (identifier == 0x9325) {Serial.println(F("Found ILI9325 LCD driver"));} else if (identifier == 0x9328) {Serial.println(F("Found ILI9328 LCD driver"));} else if (identifier == 0x7575) {Serial.println(F("Found HX8347G LCD driver"));} else if (identifier == 0x9341) {Serial.println(F("Found ILI9341 LCD driver"));} else if (identifier == 0x8357) {Serial.println(F("Found HX8357D LCD driver"));} else {Serial.print(F("Unknown LCD driver chip: "));Serial.println(identifier, HEX);Serial.println(F("If using the Adafruit 2.4\" TFT Arduino shield, the line:"));Serial.println(F(" #define USE_ADAFRUIT_SHIELD_PINOUT"));Serial.println(F("should appear in the library header (Adafruit_TFT.h)."));Serial.println(F("If using the breakout board, it should NOT be #defined!"));Serial.println(F("Also if using the breakout, double-check that all wiring"));Serial.println(F("matches the tutorial."));return;}tft.begin(identifier);Serial.println(F("Benchmark Time (microseconds)"));Serial.print(F("Screen fill "));Serial.println(FillScreen());delay(500);tft.setTextColor(YELLOW);tft.setCursor(70, 180);tft.setTextSize(1);tft.println("Electropeak");delay(200);tft.fillScreen(PURPLE);tft.setCursor(50, 170);tft.setTextSize(2);tft.println("Electropeak");delay(200);tft.fillScreen(PURPLE);tft.setCursor(20, 160);tft.setTextSize(3);tft.println("Electropeak");delay(500);tft.fillScreen(PURPLE);for (int rotation = 0; rotation < 4; rotation++) { tft.setRotation(rotation); tft.setCursor(0, 0); tft.setTextSize(3); tft.println("Electropeak"); delay(700); } delay(500); Serial.print(F("Rectangles (filled) ")); Serial.println(testFilledRects(YELLOW, MAGENTA)); delay(500); } void loop() { } unsigned long FillScreen() { unsigned long start = micros(); tft.fillScreen(RED); delay(500); tft.fillScreen(GREEN); delay(500); tft.fillScreen(BLUE); delay(500); tft.fillScreen(WHITE); delay(500); tft.fillScreen(MAGENTA); delay(500); tft.fillScreen(PURPLE); delay(500); return micros() - start; } unsigned long testFilledRects(uint16_t color1, uint16_t color2) { unsigned long start, t = 0; int n, i, i2, cx = tft.width() / 2 - 1, cy = tft.height() / 2 - 1; tft.fillScreen(BLACK); n = min(tft.width(), tft.height()); for (i = n; i > 0; i -= 6) {i2 = i / 2;start = micros();tft.fillRect(cx - i2, cy - i2, i, i, color1);t += micros() - start;// Outlines are not included in timing resultstft.drawRect(cx - i2, cy - i2, i, i, color2);}return t;}

Displaying BMP pictures/*This code is TFTLCD Library Example*/#include #include #include #include #define LCD_CS A3#define LCD_CD A2#define LCD_WR A1#define LCD_RD A0#define SD_CS 10Adafruit_TFTLCD tft(LCD_CS, LCD_CD, LCD_WR, LCD_RD, A4);void setup(){Serial.begin(9600);tft.reset();uint16_t identifier = tft.readID();if (identifier == 0x9325) {Serial.println(F("Found ILI9325 LCD driver"));} else if (identifier == 0x9328) {Serial.println(F("Found ILI9328 LCD driver"));} else if (identifier == 0x7575) {Serial.println(F("Found HX8347G LCD driver"));} else if (identifier == 0x9341) {Serial.println(F("Found ILI9341 LCD driver"));} else if (identifier == 0x8357) {Serial.println(F("Found HX8357D LCD driver"));} else {Serial.print(F("Unknown LCD driver chip: "));Serial.println(identifier, HEX);Serial.println(F("If using the Adafruit 2.4\" TFT Arduino shield, the line:"));Serial.println(F(" #define USE_ADAFRUIT_SHIELD_PINOUT"));Serial.println(F("should appear in the library header (Adafruit_TFT.h)."));Serial.println(F("If using the breakout board, it should NOT be #defined!"));Serial.println(F("Also if using the breakout, double-check that all wiring"));Serial.println(F("matches the tutorial."));return;}tft.begin(identifier);Serial.print(F("Initializing SD card..."));if (!SD.begin(SD_CS)) {Serial.println(F("failed!"));return;}Serial.println(F("OK!"));bmpDraw("pic1.bmp", 0, 0);delay(1000);bmpDraw("pic2.bmp", 0, 0);delay(1000);bmpDraw("pic3.bmp", 0, 0);delay(1000);}void loop(){}#define BUFFPIXEL 20void bmpDraw(char *filename, int x, int y) {File bmpFile;int bmpWidth, bmpHeight; // W+H in pixelsuint8_t bmpDepth; // Bit depth (currently must be 24)uint32_t bmpImageoffset; // Start of image data in fileuint32_t rowSize; // Not always = bmpWidth; may have paddinguint8_t sdbuffer[3 * BUFFPIXEL]; // pixel in buffer (R+G+B per pixel)uint16_t lcdbuffer[BUFFPIXEL]; // pixel out buffer (16-bit per pixel)uint8_t buffidx = sizeof(sdbuffer); // Current position in sdbufferboolean goodBmp = false; // Set to true on valid header parseboolean flip = true; // BMP is stored bottom-to-topint w, h, row, col;uint8_t r, g, b;uint32_t pos = 0, startTime = millis();uint8_t lcdidx = 0;boolean first = true;if ((x >= tft.width()) || (y >= tft.height())) return;Serial.println();Serial.print(F("Loading image ""));Serial.print(filename);Serial.println("\"");// Open requested file on SD cardif ((bmpFile = SD.open(filename)) == NULL) {Serial.println(F("File not found"));return;}// Parse BMP headerif (read16(bmpFile) == 0x4D42) { // BMP signatureSerial.println(F("File size: ")); Serial.println(read32(bmpFile));(void)read32(bmpFile); // Read & ignore creator bytesbmpImageoffset = read32(bmpFile); // Start of image dataSerial.print(F("Image Offset: ")); Serial.println(bmpImageoffset, DEC);// Read DIB headerSerial.print(F("Header size: ")); Serial.println(read32(bmpFile));bmpWidth = read32(bmpFile);bmpHeight = read32(bmpFile);if (read16(bmpFile) == 1) { // # planes -- must be "1"bmpDepth = read16(bmpFile); // bits per pixelSerial.print(F("Bit Depth: ")); Serial.println(bmpDepth);if ((bmpDepth == 24) && (read32(bmpFile) == 0)) { // 0 = uncompressedgoodBmp = true; // Supported BMP format -- proceed!Serial.print(F("Image size: "));Serial.print(bmpWidth);Serial.print("x");Serial.println(bmpHeight);// BMP rows are padded (if needed) to 4-byte boundaryrowSize = (bmpWidth * 3 + 3) & ~3;// If bmpHeight is negative, image is in top-down order.// This is not canon but has been observed in the wild.if (bmpHeight < 0) { bmpHeight = -bmpHeight; flip = false; } // Crop area to be loaded w = bmpWidth; h = bmpHeight; if ((x + w - 1) >= tft.width()) w = tft.width() - x;if ((y + h - 1) >= tft.height()) h = tft.height() - y;// Set TFT address window to clipped image boundstft.setAddrWindow(x, y, x + w - 1, y + h - 1);for (row = 0; row < h; row++) { // For each scanline...// Seek to start of scan line. It might seem labor-// intensive to be doing this on every line, but this// method covers a lot of gritty details like cropping// and scanline padding. Also, the seek only takes// place if the file position actually needs to change// (avoids a lot of cluster math in SD library).if (flip) // Bitmap is stored bottom-to-top order (normal BMP)pos = bmpImageoffset + (bmpHeight - 1 - row) * rowSize;else // Bitmap is stored top-to-bottompos = bmpImageoffset + row * rowSize;if (bmpFile.position() != pos) { // Need seek?bmpFile.seek(pos);buffidx = sizeof(sdbuffer); // Force buffer reload}for (col = 0; col < w; col++) { // For each column... // Time to read more pixel data? if (buffidx >= sizeof(sdbuffer)) { // Indeed// Push LCD buffer to the display firstif (lcdidx > 0) {tft.pushColors(lcdbuffer, lcdidx, first);lcdidx = 0;first = false;}bmpFile.read(sdbuffer, sizeof(sdbuffer));buffidx = 0; // Set index to beginning}// Convert pixel from BMP to TFT formatb = sdbuffer[buffidx++];g = sdbuffer[buffidx++];r = sdbuffer[buffidx++];lcdbuffer[lcdidx++] = tft.color565(r, g, b);} // end pixel} // end scanline// Write any remaining data to LCDif (lcdidx > 0) {tft.pushColors(lcdbuffer, lcdidx, first);}Serial.print(F("Loaded in "));Serial.print(millis() - startTime);Serial.println(" ms");} // end goodBmp}}bmpFile.close();if (!goodBmp) Serial.println(F("BMP format not recognized."));}// These read 16- and 32-bit types from the SD card file.// BMP data is stored little-endian, Arduino is little-endian too.// May need to reverse subscript order if porting elsewhere.uint16_t read16(File f) {uint16_t result;((uint8_t *)&result)[0] = f.read(); // LSB((uint8_t *)&result)[1] = f.read(); // MSBreturn result;}uint32_t read32(File f) {uint32_t result;((uint8_t *)&result)[0] = f.read(); // LSB((uint8_t *)&result)[1] = f.read();((uint8_t *)&result)[2] = f.read();((uint8_t *)&result)[3] = f.read(); // MSBreturn result;}

To display pictures on this LCD you should save the picture in 24bit BMP colored format and size of 240*320. Then move them to SD card and put the SD card in the LCD shield. we use the following function to display pictures. This function has 3 arguments; the first one stands for the pictures name, and the second and third arguments are for length and width coordinates of the top left corner of the picture.bmpdraw(“filename.bmp”,x,y);

Create A Paint App w/ Arduino 2.4 Touchscreen/*This code is TFTLCD Library Example*/#include #include #include #if defined(__SAM3X8E__)#undef __FlashStringHelper::F(string_literal)#define F(string_literal) string_literal#endif#define YP A3#define XM A2#define YM 9#define XP 8#define TS_MINX 150#define TS_MINY 120#define TS_MAXX 920#define TS_MAXY 940TouchScreen ts = TouchScreen(XP, YP, XM, YM, 300);#define LCD_CS A3#define LCD_CD A2#define LCD_WR A1#define LCD_RD A0#define LCD_RESET A4#define BLACK 0x0000#define BLUE 0x001F#define RED 0xF800#define GREEN 0x07E0#define CYAN 0x07FF#define MAGENTA 0xF81F#define YELLOW 0xFFE0#define WHITE 0xFFFFAdafruit_TFTLCD tft(LCD_CS, LCD_CD, LCD_WR, LCD_RD, LCD_RESET);#define BOXSIZE 40#define PENRADIUS 3int oldcolor, currentcolor;void setup(void) {Serial.begin(9600);Serial.println(F("Paint!"));tft.reset();uint16_t identifier = tft.readID();if(identifier == 0x9325) {Serial.println(F("Found ILI9325 LCD driver"));} else if(identifier == 0x9328) {Serial.println(F("Found ILI9328 LCD driver"));} else if(identifier == 0x7575) {Serial.println(F("Found HX8347G LCD driver"));} else if(identifier == 0x9341) {Serial.println(F("Found ILI9341 LCD driver"));} else if(identifier == 0x8357) {Serial.println(F("Found HX8357D LCD driver"));} else {Serial.print(F("Unknown LCD driver chip: "));Serial.println(identifier, HEX);Serial.println(F("If using the Adafruit 2.4\" TFT Arduino shield, the line:"));Serial.println(F(" #define USE_ADAFRUIT_SHIELD_PINOUT"));Serial.println(F("should appear in the library header (Adafruit_TFT.h)."));Serial.println(F("If using the breakout board, it should NOT be #defined!"));Serial.println(F("Also if using the breakout, double-check that all wiring"));Serial.println(F("matches the tutorial."));return;}tft.begin(identifier);tft.fillScreen(BLACK);tft.fillRect(0, 0, BOXSIZE, BOXSIZE, RED);tft.fillRect(BOXSIZE, 0, BOXSIZE, BOXSIZE, YELLOW);tft.fillRect(BOXSIZE*2, 0, BOXSIZE, BOXSIZE, GREEN);tft.fillRect(BOXSIZE*3, 0, BOXSIZE, BOXSIZE, CYAN);tft.fillRect(BOXSIZE*4, 0, BOXSIZE, BOXSIZE, BLUE);tft.fillRect(BOXSIZE*5, 0, BOXSIZE, BOXSIZE, MAGENTA);tft.drawRect(0, 0, BOXSIZE, BOXSIZE, WHITE);currentcolor = RED;pinMode(13, OUTPUT);}#define MINPRESSURE 10#define MAXPRESSURE 1000void loop(){digitalWrite(13, HIGH);TSPoint p = ts.getPoint();digitalWrite(13, LOW);pinMode(XM, OUTPUT);pinMode(YP, OUTPUT);if (p.z > MINPRESSURE && p.z < MAXPRESSURE) {if (p.y < (TS_MINY-5)) {Serial.println("erase");tft.fillRect(0, BOXSIZE, tft.width(), tft.height()-BOXSIZE, BLACK);}p.x = map(p.x, TS_MINX, TS_MAXX, tft.width(), 0);p.y = map(p.y, TS_MINY, TS_MAXY, tft.height(), 0);if (p.y < BOXSIZE) {oldcolor = currentcolor;if (p.x < BOXSIZE) {currentcolor = RED;tft.drawRect(0, 0, BOXSIZE, BOXSIZE, WHITE);} else if (p.x < BOXSIZE*2) {currentcolor = YELLOW;tft.drawRect(BOXSIZE, 0, BOXSIZE, BOXSIZE, WHITE);} else if (p.x < BOXSIZE*3) {currentcolor = GREEN;tft.drawRect(BOXSIZE*2, 0, BOXSIZE, BOXSIZE, WHITE);} else if (p.x < BOXSIZE*4) {currentcolor = CYAN;tft.drawRect(BOXSIZE*3, 0, BOXSIZE, BOXSIZE, WHITE);} else if (p.x < BOXSIZE*5) {currentcolor = BLUE;tft.drawRect(BOXSIZE*4, 0, BOXSIZE, BOXSIZE, WHITE);} else if (p.x < BOXSIZE*6) { currentcolor = MAGENTA; tft.drawRect(BOXSIZE*5, 0, BOXSIZE, BOXSIZE, WHITE); } if (oldcolor != currentcolor) { if (oldcolor == RED) tft.fillRect(0, 0, BOXSIZE, BOXSIZE, RED); if (oldcolor == YELLOW) tft.fillRect(BOXSIZE, 0, BOXSIZE, BOXSIZE, YELLOW); if (oldcolor == GREEN) tft.fillRect(BOXSIZE*2, 0, BOXSIZE, BOXSIZE, GREEN); if (oldcolor == CYAN) tft.fillRect(BOXSIZE*3, 0, BOXSIZE, BOXSIZE, CYAN); if (oldcolor == BLUE) tft.fillRect(BOXSIZE*4, 0, BOXSIZE, BOXSIZE, BLUE); if (oldcolor == MAGENTA) tft.fillRect(BOXSIZE*5, 0, BOXSIZE, BOXSIZE, MAGENTA); } } if (((p.y-PENRADIUS) > BOXSIZE) && ((p.y+PENRADIUS) < tft.height())) {tft.fillCircle(p.x, p.y, PENRADIUS, currentcolor);}}}

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.

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.

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.

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.

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 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.

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 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.

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 guide we’re going to show you how you can use the 1.8 TFT display with the Arduino. You’ll learn how to wire the display, write text, draw shapes and display images on the screen.

The 1.8 TFT is a colorful display with 128 x 160 color pixels. The display can load images from an SD card – it has an SD card slot at the back. The following figure shows the screen front and back view.

This module uses SPI communication – see the wiring below . To control the display we’ll use the TFT library, which is already included with Arduino IDE 1.0.5 and later.

The TFT display communicates with the Arduino via SPI communication, so you need to include the SPI library on your code. We also use the TFT library to write and draw on the display.

The 1.8 TFT display can load images from the SD card. To read from the SD card you use the SD library, already included in the Arduino IDE software. Follow the next steps to display an image on the display:

In this guide we’ve shown you how to use the 1.8 TFT display with the Arduino: display text, draw shapes and display images. You can easily add a nice visual interface to your projects using this display.

Spice up your Arduino project with a beautiful large touchscreen display shield with built in microSD card connection. This TFT display is big 4"(3.97" diagonal) bright (6 white-LED backlight) and colorful (18-bit 262,000 different shades)! 480x800 pixels with individual pixel control. As a bonus, this display has a optional resistive touch panel with controller XPT2046 and capacitive touch panel with FT6336.

The shield is fully assembled, tested and ready to go. No wiring, no soldering! Simply plug it in and load up our library - you"ll have it running in under 10 minutes! Works best with any classic Arduino (Due/Mega 2560).

This display shield has a controller built into it with RAM buffering, so that almost no work is done by the microcontroller. You can connect more sensors, buttons and LEDs.

Let us start with the basics first; refresh the knowledge about TN and LCD displays in general, later we will talk about TFTs (Thin Film Transistors), how they differ from regular monochrome LCD displays. Then we will go on to the ghosting effect, so we will not only discuss the technology behind the construction of the TFT, but also some phenomena, like the ghosting effect, or grayscale inversion, that are important to understand when using an LCD TFT display.

Next, we will look at different technologies of the TFT LCD displays like TN, IPS, VA, and of course about transmissive and transflective LCD displays, because TFT displays also can be transmissive and transflective. In the last part we will talk about backlight.

Let us start with a short review of the most basic liquid crystal cell, which is the TN (twisted nematic) display. On the picture above, we can see that the light can be transmit through the cell or blocked by the liquid crystal cell using voltage. If you want to learn more about monochrome LCD displays and the basics of LCD displays, follow this link.

What is a TFT LCD display and how it is different from a monochrome LCD display? TFT is called an active display. Active, means we have one or more transistors in every cell, in every pixel and in every subpixel. TFT stands for Thin Film Transistor, transistors that are very small and very thin and are built into the pixel, so they are not somewhere outside in a controller, but they are in the pixel itself. For example, in a 55-inch TV set, the TFT display contains millions of transistors in the pixels. We do not see them, because they are very small and hidden, if we zoom in, however, we can see them in every corner of each pixel, like on the picture below.

On the picture above we can see subpixels, that are basic RGB (Red, Green, Blue) colors and a black part, with the transistors and electronic circuits. We just need to know that we have pixels, and subpixels, and each subpixel has transistors. This makes the display active, and thus is called  the TFT display. TFT displays are usually color displays, but there are also monochrome TFT displays, that are active, and have transistors, but have no colors. The colors in the TFT LCD display are typically added by color filters on each subpixel. Usually the filters are RGB, but we also have RGBW (Red, Green, Blue, White) LCD displays with added subpixels without the filter (White) to make the display brighter.

What is interesting, the white part of the RGB and RGBW screen will look exactly the same from a distance, because the lights are mixed and generate white light, but when we come closer to the screen, we will not see white light at all.

Going a little bit deeper, into the TFT cell, there is a part inside well known to us from the monochrome LCD display Riverdi University lecture. We have a cell, liquid crystal, polarizers, an ITO (Indium Tin Oxide) layer for the electrodes, and additionally an electronic circuit. Usually, the electronic circuit consists of one transistor and some capacitors to sustain the pixel state when we switch the pixel OFF and ON. In a TFT LCD display the pixels are much more complicated because apart from building the liquid crystal part, we also need to build an electronic part.

That is why TFT LCD display technologies are very expensive to manufacture. If you are familiar with electronics, you know that the transistor is a kind of switch, and it allows us to switch the pixel ON and OFF. Because it is built into the pixel itself, it can be done very quickly and be very well controlled. We can control the exact state of every pixel not only the ON and OFF states, but also all the states in between. We can switch the light of the cells ON and OFF in several steps. Usually for TFT LCD displays it will be 8-bit steps per color, so we have 256 steps of brightness for every color, and every subpixel. Because we have three subpixels, we have a 24-bit color range, that means over 16 million combinations, we can, at least theoretically, show on our TFT LCD display over 16 million distinct colors using RGB pixels.

Now that we know how the TFT LCD display works, we can now learn some practical things one of which is LCD TFT ghosting. We know how the image is created, but what happens when we have the image on the screen for a prolonged time, and how to prevent it. In LCD displays we have something called LCD ghosting. We do not see it very often, but in some displays this phenomenon still exists.

Another issue present in TFT displays, especially TN LCD displays, is grayscale inversion. This is a phenomenon that changes the colors of the screen according to the viewing angle, and it is only one-sided. When buying a TFT LCD display, first we need to check what kind of technology it is. If it is an IPS display, like the Riverdi IPS display line, then we do not need to worry about the grayscale inversion because all the viewing angles will be the same and all of them will be very high, like 80, 85, or 89 degrees. But if you buy a more common or older display technology type, like the TN (twisted nematic) display, you need to think where it will be used, because one viewing angle will be out. It may be sometimes confusing, and you need to be careful as most factories define viewing direction of the screen and mistake this with the greyscale inversion side.

We know already that TN (twisted nematic) displays, suffer from grayscale inversion, which means the display has one viewing side, where the image color suddenly changes. It is tricky, and you need to be careful. On the picture above there is a part of the LCD TFT specification of a TN (twisted nematic) display, that has grayscale inversion, and if we go to this table, we can see the viewing angles. They are defined at 70, 70, 60 and 70 degrees, that is the maximum viewing angle, at which the user can see the image. Normally we may think that 70 degrees is better, so we will choose left and right side to be 70 degrees, and then up and down, and if we do not know the grayscale inversion phenomena, we may put our user on the bottom side which is also 70 degrees. The viewing direction will be then like a 6 o’clock direction, so we call it a 6 o’clock display. But you need to be careful! Looking at the specification, we can see that this display was defined as a 12 o’clock display, so it is best for it to be seen from a 12 o’clock direction. But we can find that the 12 o’clock has a lower viewing angle – 60 degrees. What does it mean? It means that on this side there will be no grayscale inversion. If we go to 40, 50, 60 degrees and even a little bit more, probably we will still see the image properly. Maybe with lower contrast, but the colors will not change. If we go from the bottom, from a 6 o’clock direction where we have the grayscale inversion, after 70 degrees or lower we will see a sudden color change, and of course this is something we want to avoid.

We will talk now about the other TFT technologies, that allow us to have wider viewing angles and more vivid colors. The most basic technology for monochrome and TFT LCD displays is twisted nematic (TN). As we already know, this kind of displays have a problem with grayscale inversion. On one side we have a higher retardation and will not get a clear image. That is why we have other technologies like VA (Vertical Alignment), where the liquid crystal is differently organized, and another variation of the TFT technology – IPS which is In-Plane Switching. The VA and IPS LCD displays do not have a problem with the viewing angles, you can see a clear image from all sides.

Apart from the different organization of the liquid crystals, we also organize subpixels a little bit differently in a VA and IPS LCD displays. When we look closer at the TN display, we will just see the subpixels with color filters. If we look at the VA or IPS display they will have subpixels of subpixels. The subpixels are divided into smaller parts. In this way we can achieve even wider viewing angles and better colors for the user, but of course, it is more complicated and more expensive to do.

The picture above presents the TN display and grayscale inversion. For IPS or VA technology there is no such effect. The picture will be the same from all the sides we look so these technologies are popular where we need wide viewing angles, and TN is popular where we don’t need that, like in monitors. Other advantages of IPS LCD displays are they give accurate colors, and wide viewing angles. What is also important in practice, in our projects, is that the IPS LCD displays are less susceptible to mechanical force. When we apply mechanical force to the screen, and have an optically bonded touch screen, we push the display as well as squeeze the cells. When we have a TN display, every push on the cell changes the image suddenly, with the IPS LCD displays with in-plane switching, different liquid crystals organization, this effect is lesser. It is not completely removed but it is much less distinct. That is another reason IPS displays are very popular for smartphones, tablets, when we have the touchscreens usually optically bonded.

Now, let us look at the backlight types. As we see here, on the picture above, we have four distinct types of backlight possible. The most common, 95 or 99 per cent of the TFT LCD displays on the market are the transmissive LCD display type, where we need the backlight from the back. If you remember from our Monochrome LCD Displays lecture, for transmissive LCD displays you need the backlight to be always on. If you switch the backlight off, you will not see anything. The same as for monochrome LCD displays, but less popular for TFT displays, we have the transflective LCD display type. They are not popular because usually for transflective TFT displays, the colors lack in brightness, and the displays are not very practical to use. You can see the screen, but the application is limited. Some transflective LCD displays are used by military, in applications where power consumption is paramount; where you can switch the backlight off and you agree to have lower image quality but still see the image. Power consumption and saving energy is most important in some kind of applications and you can use transflective LCD displays there. The reflective type of LCD displays are almost never used in TFT. There is one technology called Low Power Reflective Displays (LPRD) that is used in TFT but it is not popular. Lastly, we have a variation of reflective displays with frontlight, where we add frontlight to the reflective display and have the image even without external light.

Just a few words about Low Power Reflective Displays (LPRD). This kind of display uses environmental light, ambient light to reflect, and produce some colors. The colors are not perfect, not perfectly clear, but this technology is becoming increasingly popular because it allows to have color displays in battery powered applications. For example, a smartwatch would be a case for that technology, or an electrical bike or scooter, where we can not only have a standard monochrome LCD display but also a TFT LCD color display without the backlight; we can see the image even in

strong sunlight and not need backlight at all. So, this kind of TFL LCD display technology is getting more and more popular when we have outdoor LCD displays and need a low power consumption.

On the picture above, we have some examples of how transmissive and reflective LCD displays work in the sunlight. If we have a simple image, like a black and white pattern, then on a transmissive LCD display, even with 1000 candela brightness, the image probably will be lower quality than for a reflective LCD display; if we have sunlight, we have very strong light reflections on the surface of the screen. We have talked about contrast in more detail in the lecture Sunlight Readable Displays. So, reflective LCD displays are a better solution for outdoor applications than transmissive LCD displays, where you need a really strong backlight, 1000 candela or more, to be really seen outdoors.

To show you how the backlight of LCD displays is built, we took the picture above. You can see the edge backlight there, where we have LEDs here on the small PCB on the edge, and we have a diffuser that distributes the light to the whole surface of LCD screen.

In addition to the backlight, we have something that is called a frontlight. It is similar to backlight, it also uses the LEDs to put the light into it, but the frontlight needs to be transparent as we have the display behind. On the example on the picture above we can see an e-paper display. The e-paper display is also a TFT display variation, but it is not LCD (liquid crystal), it is a different technology, but the back of the display is the same and it is reflective. The example you see is the Kindle 4 eBook reader. It uses an e-paper display and a frontlight as well, so you can read eBooks even during the night.

As you may have read in the previous post, after careful consideration I ordered up a bunch of hardware. For the sake of this article, however, only two items will be important from that list. They are the Seeeduino Mega 2560 ADK dev board and the 2.8″ TFT Touch Shield. The problem I was experiencing was that when I plugged the 2.8″ TFT Touch Shield (“shield”) into the Seeeduino Mega 2560 ADK (“Seeeduino”), all I got was a white background with the backlight on. There was nothing else going on. I tried just about every library under the sun, every example, my own code, searching Google for solutions, etc. I saw that lots of folks were having this problem, but no one had any solutions. So, I eventually posted the problem to the Seeduino forums.

Due to this difference the screen has to use different pins. Unfortunately the example sketches in the TFT library don’t tell you that you have to change anything so what you wind up with on the Mega 2560 boards is the TFT screen with a blank white background and the backlight on.

Congratulations! You’ve successfully fixed the TFT library so that you can use it with a Arduino or Seeeduino Mega 2560 or Mega 2560 ADK! On my board I tested it out and everything was great after that! Try the drawCircle sketch from the library examples once you fix this.

Arduino has always helped to build projects easily and make them look more attractive.  Programming an LCD screen with touch screen option might sound as a complicated task, but the Arduino libraries and shields had made it really easy. In this project we will use a 2.4” Arduino TFT LCD screen to build our own Arduino Touch Screen calculator that could perform all basic calculations like Addition, Subtraction, Division and Multiplication.

Before we actually dive into the project it is important to know, how this 2.4” TFT LCD Module works and what are the types present in it. Let us take a look at the pinouts of this 2.4” TFT LCD screen module.

As you can see the pins can be classified in to four main classifications such as LCD Command Pins, LCD Data Pins, SD Card Pins and Power Pins, We need not know much about the detailed working of these pins since they will be take care by our Arduino Library.

You can also find an SD card slot at the bottom of the module shown above, which can be used to load an SD card with bmp image files, and these images can be displayed in our TFT LCD screen using the Arduino Program.

Another important thing to note is your Interface IC. There are many types of TFT modules available in the market starting from the original Adafruit TFT LCD module to cheap Chinese clones. A program which works perfectly for your Adafruit shield might not work the same for Chinese breakout boards. So, it is very important to know which types of LCD display your are holding in hand. This detail has to be obtained from the vendor. If you are having a cheap clone like mine then it is most probably using the ili9341 driver IC.You can follow this TFT LCD interfacing with Arduino tutorial to try out some basic example programs and get comfortable with the LCD screen. Also check out our other TFT LCD projects with Arduino here:

If you planning to use the touch screen function of your TFT LCD module, then you have to calibrate it to make it work properly.  A LCD screen without calibration might work unlikely, for instance you might touch at one place and the TFT might respond for a touch at some other place. These calibrations results will not be similar for all boards and hence you are left on your own to do this.

The 2.4” TFT LCD screen is a perfect Arduino Shield. You can directly push the LCD screen on top of the Arduino Uno and it will perfectly match with the pins and slid in through. However, as matters of safety cover the Programming terminal of your Arduino UNO with a small insulation tape, just in case if the terminal comes in contact with your TFT LCD screen. The LCD assembled on UNO will look something like this below.

We are using the SPFD5408 Library to get this arduino calculator code working. This is a modified library of Adafruit and can work seamlessly with our LCD TFT Module. You can check the complete program at the end of this Article.

As said earlier we need to calibrate the LCD screen to make it work as expected, but don’t worry the values given here are almost universal. The variables TS_MINX, TS_MINY, TS_MAXX, and TS_MAXY decide the calibration of the Screen. You can toy around them if you feel the calibration is not satisfactory.

As we know the TFT LCD screen can display a lot of colours, all these colours have to be entered in hex value. To make it more human readable we assign these values to a variable as shown below.

The final step is to calculate the result and display them on TFT LCD Screen. This arduino calculator can perform operation with 2 numbers only. These two numbers are named as variables “Num1” and “Num2”. The variable “Number” gives and takes value from Num1 and Num2 and also bears the result.

The working of this Arduino Touch Screen Calculator is simple. You have to upload the below given code on your Arduino and fire it up. You get the calculator displayed on your LCD screen.

Hi guys, welcome to today’s tutorial. Today, we will look on how to use the 1.8″ ST7735  colored TFT display with Arduino. The past few tutorials have been focused on how to use the Nokia 5110 LCD display extensively but there will be a time when we will need to use a colored display or something bigger with additional features, that’s where the 1.8″ ST7735 TFT display comes in.

The ST7735 TFT display is a 1.8″ display with a resolution of 128×160 pixels and can display a wide range of colors ( full 18-bit color, 262,144 shades!). The display uses the SPI protocol for communication and has its own pixel-addressable frame buffer which means it can be used with all kinds of microcontroller and you only need 4 i/o pins. To complement the display, it also comes with an SD card slot on which colored bitmaps can be loaded and easily displayed on the screen.

Due to variation in display pin out from different manufacturers and for clarity, the pin connection between the Arduino and the TFT display is mapped out below:

We will use two libraries from Adafruit to help us easily communicate with the LCD. The libraries include the Adafruit GFX library which can be downloaded here and the Adafruit ST7735 Library which can be downloaded here.

We will use two example sketches to demonstrate the use of the ST7735 TFT display. The first example is the lightweight TFT Display text example sketch from the Adafruit TFT examples. It can be accessed by going to examples -> TFT -> Arduino -> TFTDisplaytext. This example displays the analog value of pin A0 on the display. It is one of the easiest examples that can be used to demonstrate the ability of this display.

The first thing, as usual, is to include the libraries to be used after which we declare the pins on the Arduino to which our LCD pins are connected to. We also make a slight change to the code setting reset pin as pin 8 and DC pin as pin 9 to match our schematics.

Next, we create an object of the library with the pins to which the LCD is connected on the Arduino as parameters. There are two options for this, feel free to choose the most preferred.

testdrawtext("Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur adipiscing ante sed nibh tincidunt feugiat. Maecenas enim massa, fringilla sed malesuada et, malesuada sit amet turpis. Sed porttitor neque ut ante pretium vitae malesuada nunc bibendum. Nullam aliquet ultrices massa eu hendrerit. Ut sed nisi lorem. In vestibulum purus a tortor imperdiet posuere. ", ST7735_WHITE);

testdrawtext("Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur adipiscing ante sed nibh tincidunt feugiat. Maecenas enim massa, fringilla sed malesuada et, malesuada sit amet turpis. Sed porttitor neque ut ante pretium vitae malesuada nunc bibendum. Nullam aliquet ultrices massa eu hendrerit. Ut sed nisi lorem. In vestibulum purus a tortor imperdiet posuere. ", ST77XX_WHITE);

Please don"t mark this question as duplicated because I looked at the other guy he/she was using different guide.. the one I"m using is posted by the company I purchased the TFT from.

A thin-film-transistor liquid-crystal display (TFT LCD) is a variant of a liquid-crystal display that uses thin-film-transistor technologyactive matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven (i.e. with segments directly connected to electronics outside the LCD) LCDs with a few segments.

In February 1957, John Wallmark of RCA filed a patent for a thin film MOSFET. Paul K. Weimer, also of RCA implemented Wallmark"s ideas and developed the thin-film transistor (TFT) in 1962, a type of MOSFET distinct from the standard bulk MOSFET. It was made with thin films of cadmium selenide and cadmium sulfide. The idea of a TFT-based liquid-crystal display (LCD) was conceived by Bernard Lechner of RCA Laboratories in 1968. In 1971, Lechner, F. J. Marlowe, E. O. Nester and J. Tults demonstrated a 2-by-18 matrix display driven by a hybrid circuit using the dynamic scattering mode of LCDs.T. Peter Brody, J. A. Asars and G. D. Dixon at Westinghouse Research Laboratories developed a CdSe (cadmium selenide) TFT, which they used to demonstrate the first CdSe thin-film-transistor liquid-crystal display (TFT LCD).active-matrix liquid-crystal display (AM LCD) using CdSe TFTs in 1974, and then Brody coined the term "active matrix" in 1975.high-resolution and high-quality electronic visual display devices use TFT-based active matrix displays.

The circuit layout process of a TFT-LCD is very similar to that of semiconductor products. However, rather than fabricating the transistors from silicon, that is formed into a crystalline silicon wafer, they are made from a thin film of amorphous silicon that is deposited on a glass panel. The silicon layer for TFT-LCDs is typically deposited using the PECVD process.

Polycrystalline silicon is sometimes used in displays requiring higher TFT performance. Examples include small high-resolution displays such as those found in projectors or viewfinders. Amorphous silicon-based TFTs are by far the most common, due to their lower production cost, whereas polycrystalline silicon TFTs are more costly and much more difficult to produce.

The twisted nematic display is one of the oldest and frequently cheapest kind of LCD display technologies available. TN displays benefit from fast pixel response times and less smearing than other LCD display technology, but suffer from poor color reproduction and limited viewing angles, especially in the vertical direction. Colors will shift, potentially to the point of completely inverting, when viewed at an angle that is not perpendicular to the display. Modern, high end consumer products have developed methods to overcome the technology"s shortcomings, such as RTC (Response Time Compensation / Overdrive) technologies. Modern TN displays can look significantly better than older TN displays from decades earlier, but overall TN has inferior viewing angles and poor color in comparison to other technology.

The transmittance of a pixel of an LCD panel typically does not change linearly with the applied voltage,sRGB standard for computer monitors requires a specific nonlinear dependence of the amount of emitted light as a function of the RGB value.

Less expensive PVA panels often use dithering and FRC, whereas super-PVA (S-PVA) panels all use at least 8 bits per color component and do not use color simulation methods.BRAVIA LCD TVs offer 10-bit and xvYCC color support, for example, the Bravia X4500 series. S-PVA also offers fast response times using modern RTC technologies.

TFT dual-transistor pixel or cell technology is a reflective-display technology for use in very-low-power-consumption applications such as electronic shelf labels (ESL), digital watches, or metering. DTP involves adding a secondary transistor gate in the single TFT cell to maintain the display of a pixel during a period of 1s without loss of image or without degrading the TFT transistors over time. By slowing the refresh rate of the standard frequency from 60 Hz to 1 Hz, DTP claims to increase the power efficiency by multiple orders of magnitude.

Due to the very high cost of building TFT factories, there are few major OEM panel vendors for large display panels. The glass panel suppliers are as follows:

External consumer display devices like a TFT LCD feature one or more analog VGA, DVI, HDMI, or DisplayPort interface, with many featuring a selection of these interfaces. Inside external display devices there is a controller board that will convert the video signal using color mapping and image scaling usually employing the discrete cosine transform (DCT) in order to convert any video source like CVBS, VGA, DVI, HDMI, etc. into digital RGB at the native resolution of the display panel. In a laptop the graphics chip will directly produce a signal suitable for connection to the built-in TFT display. A control mechanism for the backlight is usually included on the same controller board.

The low level interface of STN, DSTN, or TFT display panels use either single ended TTL 5 V signal for older displays or TTL 3.3 V for slightly newer displays that transmits the pixel clock, horizontal sync, vertical sync, digital red, digital green, digital blue in parallel. Some models (for example the AT070TN92) also feature input/display enable, horizontal scan direction and vertical scan direction signals.

New and large (>15") TFT displays often use LVDS signaling that transmits the same contents as the parallel interface (Hsync, Vsync, RGB) but will put control and RGB bits into a number of serial transmission lines synchronized to a clock whose rate is equal to the pixel rate. LVDS transmits seven bits per clock per data line, with six bits being data and one bit used to signal if the other six bits need to be inverted in order to maintain DC balance. Low-cost TFT displays often have three data lines and therefore only directly support 18 bits per pixel. Upscale displays have four or five data lines to support 24 bits per pixel (truecolor) or 30 bits per pixel respectively. Panel manufacturers are slowly replacing LVDS with Internal DisplayPort and Embedded DisplayPort, which allow sixfold reduction of the number of differential pairs.

Kawamoto, H. (2012). "The Inventors of TFT Active-Matrix LCD Receive the 2011 IEEE Nishizawa Medal". Journal of Display Technology. 8 (1): 3–4. Bibcode:2012JDisT...8....3K. doi:10.1109/JDT.2011.2177740. ISSN 1551-319X.

K. H. Lee; H. Y. Kim; K. H. Park; S. J. Jang; I. C. Park & J. Y. Lee (June 2006). "A Novel Outdoor Readability of Portable TFT-LCD with AFFS Technology". SID Symposium Digest of Technical Papers. AIP. 37 (1): 1079–82. doi:10.1889/1.2433159. S2CID 129569963.