This tutorial explains how to use an ILI9341 with a touchscreen driven by an esp32-s2!
Supplies
- (1) esp32-s2-12k
- (13) Jumper wires
- (1) ILI9341 with Touchscreen
For refrence I have included the pinout diagram for the esp32-c3-32s that I am using.

I have included the specsheet for this chip in case it is removed, the original source location is https://docs.ai-thinker.com/en/12k_development_board_esp32-s2
Checkup
It's always good to double-check we are using the right screen as many screens look touch-capable but are not. Check out the steps to make sure they are by reading https://www.gabrielcsapo.com/hardware-how-to-identify-an-ili9341-that-supports-touch/.
Setup
Alright, now that we have figured out if the touchscreen you have is touch-capable, time to set up the esp32-s2-12k and the ILI9341 display.
esp32-s2-12k Pins | TFT Pins |
---|---|
3V3 | VCC |
GND | GND |
10 | CS |
15 | RESET |
11 | SDI (MOSI) |
12 | SCK |
3V3 | LED |
12 | T_CLK |
34 | T_CS |
11 | T_DIN |
13 | T_DO |

Coding
There are, like most things, multiple ways you can program this board to support touch and display out.
Flash settings
- USB CDC on boot: disabled
- Board: ESP32S2 Dev Modules
- CPU Frequency: 240MHZ
- Flash Frequency: 40MHZ
- Flash Mode: DIO
- Flash Size: 4MB
- Partition Scheme: Default 4MB with spiffs
- Upload Mode: UARTO
- Upload Speed: 460800
TFT_eSPI
We are using the following libraries:
For information on how to install the libraries above please visist https://www.arduino.cc/en/guide/libraries.
Working with TFT_eSPI, you need to edit User_Setup.h
it is located in your Arduino folder libraries folder. To find this location check out https://support.arduino.cc/hc/en-us/articles/4411202655634-Find-Arduino-IDE-files-and-folders which has more info on the exact location for your machine.
#define ILI9341_DRIVER
#define TFT_CS 10
#define TFT_MOSI 11
#define TFT_SCLK 12
#define TFT_MISO 13
#define TFT_DC 14
#define TFT_RST 15
#define TOUCH_CS 34
#define LOAD_GLCD
#define LOAD_FONT2
#define LOAD_FONT4
#define LOAD_FONT6
#define LOAD_FONT7
#define LOAD_FONT8
#define LOAD_GFXFF
#define SMOOTH_FONT
#define USE_HSPI_PORT
#define SPI_FREQUENCY 40000000
#define SPI_TOUCH_FREQUENCY 2500000
Once we have the User_Setup.h
configured we can use one of the existing sketches. One of the most intricate examples is the keypad example (https://github.com/Bodmer/TFT_eSPI/blob/master/examples/320 x 240/Keypad_240x320/Keypad_240x320.ino). It shows off having a single library handle both touch and rendering provides a lot of out of the box wins.
/*
The TFT_eSPI library incorporates an Adafruit_GFX compatible
button handling class, this sketch is based on the Arduin-o-phone
example.
This example diplays a keypad where numbers can be entered and
send to the Serial Monitor window.
The sketch has been tested on the ESP8266 (which supports SPIFFS)
The minimum screen size is 320 x 240 as that is the keypad size.
*/
// The SPIFFS (FLASH filing system) is used to hold touch screen
// calibration data
#include "FS.h"
#include <SPI.h>
#include <TFT_eSPI.h> // Hardware-specific library
TFT_eSPI tft = TFT_eSPI(); // Invoke custom library
// This is the file name used to store the calibration data
// You can change this to create new calibration files.
// The SPIFFS file name must start with "/".
#define CALIBRATION_FILE "/TouchCalData1"
// Set REPEAT_CAL to true instead of false to run calibration
// again, otherwise it will only be done once.
// Repeat calibration if you change the screen rotation.
#define REPEAT_CAL false
// Keypad start position, key sizes and spacing
#define KEY_X 40 // Centre of key
#define KEY_Y 96
#define KEY_W 62 // Width and height
#define KEY_H 30
#define KEY_SPACING_X 18 // X and Y gap
#define KEY_SPACING_Y 20
#define KEY_TEXTSIZE 1 // Font size multiplier
// Using two fonts since numbers are nice when bold
#define LABEL1_FONT &FreeSansOblique12pt7b // Key label font 1
#define LABEL2_FONT &FreeSansBold12pt7b // Key label font 2
// Numeric display box size and location
#define DISP_X 1
#define DISP_Y 10
#define DISP_W 238
#define DISP_H 50
#define DISP_TSIZE 3
#define DISP_TCOLOR TFT_CYAN
// Number length, buffer for storing it and character index
#define NUM_LEN 12
char numberBuffer[NUM_LEN + 1] = "";
uint8_t numberIndex = 0;
// We have a status line for messages
#define STATUS_X 120 // Centred on this
#define STATUS_Y 65
// Create 15 keys for the keypad
char keyLabel[15][5] = {"New", "Del", "Send", "1", "2", "3", "4", "5", "6", "7", "8", "9", ".", "0", "#" };
uint16_t keyColor[15] = {TFT_RED, TFT_DARKGREY, TFT_DARKGREEN,
TFT_BLUE, TFT_BLUE, TFT_BLUE,
TFT_BLUE, TFT_BLUE, TFT_BLUE,
TFT_BLUE, TFT_BLUE, TFT_BLUE,
TFT_BLUE, TFT_BLUE, TFT_BLUE
};
// Invoke the TFT_eSPI button class and create all the button objects
TFT_eSPI_Button key[15];
//------------------------------------------------------------------------------------------
void setup() {
// Use serial port
Serial.begin(9600);
// Initialise the TFT screen
tft.init();
// Set the rotation before we calibrate
tft.setRotation(0);
// Calibrate the touch screen and retrieve the scaling factors
touch_calibrate();
// Clear the screen
tft.fillScreen(TFT_BLACK);
// Draw keypad background
tft.fillRect(0, 0, 240, 320, TFT_DARKGREY);
// Draw number display area and frame
tft.fillRect(DISP_X, DISP_Y, DISP_W, DISP_H, TFT_BLACK);
tft.drawRect(DISP_X, DISP_Y, DISP_W, DISP_H, TFT_WHITE);
// Draw keypad
drawKeypad();
}
//------------------------------------------------------------------------------------------
void loop(void) {
uint16_t t_x = 0, t_y = 0; // To store the touch coordinates
// Pressed will be set true is there is a valid touch on the screen
bool pressed = tft.getTouch(&t_x, &t_y);
// / Check if any key coordinate boxes contain the touch coordinates
for (uint8_t b = 0; b < 15; b++) {
if (pressed && key[b].contains(t_x, t_y)) {
key[b].press(true); // tell the button it is pressed
} else {
key[b].press(false); // tell the button it is NOT pressed
}
}
// Check if any key has changed state
for (uint8_t b = 0; b < 15; b++) {
if (b < 3) tft.setFreeFont(LABEL1_FONT);
else tft.setFreeFont(LABEL2_FONT);
if (key[b].justReleased()) key[b].drawButton(); // draw normal
if (key[b].justPressed()) {
key[b].drawButton(true); // draw invert
// if a numberpad button, append the relevant # to the numberBuffer
if (b >= 3) {
if (numberIndex < NUM_LEN) {
numberBuffer[numberIndex] = keyLabel[b][0];
numberIndex++;
numberBuffer[numberIndex] = 0; // zero terminate
}
status(""); // Clear the old status
}
// Del button, so delete last char
if (b == 1) {
numberBuffer[numberIndex] = 0;
if (numberIndex > 0) {
numberIndex--;
numberBuffer[numberIndex] = 0;//' ';
}
status(""); // Clear the old status
}
if (b == 2) {
status("Sent value to serial port");
Serial.println(numberBuffer);
}
// we dont really check that the text field makes sense
// just try to call
if (b == 0) {
status("Value cleared");
numberIndex = 0; // Reset index to 0
numberBuffer[numberIndex] = 0; // Place null in buffer
}
// Update the number display field
tft.setTextDatum(TL_DATUM); // Use top left corner as text coord datum
tft.setFreeFont(&FreeSans18pt7b); // Choose a nicefont that fits box
tft.setTextColor(DISP_TCOLOR); // Set the font colour
// Draw the string, the value returned is the width in pixels
int xwidth = tft.drawString(numberBuffer, DISP_X + 4, DISP_Y + 12);
// Now cover up the rest of the line up by drawing a black rectangle. No flicker this way
// but it will not work with italic or oblique fonts due to character overlap.
tft.fillRect(DISP_X + 4 + xwidth, DISP_Y + 1, DISP_W - xwidth - 5, DISP_H - 2, TFT_BLACK);
delay(10); // UI debouncing
}
}
}
//------------------------------------------------------------------------------------------
void drawKeypad()
{
// Draw the keys
for (uint8_t row = 0; row < 5; row++) {
for (uint8_t col = 0; col < 3; col++) {
uint8_t b = col + row * 3;
if (b < 3) tft.setFreeFont(LABEL1_FONT);
else tft.setFreeFont(LABEL2_FONT);
key[b].initButton(&tft, KEY_X + col * (KEY_W + KEY_SPACING_X),
KEY_Y + row * (KEY_H + KEY_SPACING_Y), // x, y, w, h, outline, fill, text
KEY_W, KEY_H, TFT_WHITE, keyColor[b], TFT_WHITE,
keyLabel[b], KEY_TEXTSIZE);
key[b].drawButton();
}
}
}
//------------------------------------------------------------------------------------------
void touch_calibrate()
{
uint16_t calData[5];
uint8_t calDataOK = 0;
// check file system exists
if (!SPIFFS.begin()) {
Serial.println("Formating file system");
SPIFFS.format();
SPIFFS.begin();
}
// check if calibration file exists and size is correct
if (SPIFFS.exists(CALIBRATION_FILE)) {
if (REPEAT_CAL)
{
// Delete if we want to re-calibrate
SPIFFS.remove(CALIBRATION_FILE);
}
else
{
File f = SPIFFS.open(CALIBRATION_FILE, "r");
if (f) {
if (f.readBytes((char *)calData, 14) == 14)
calDataOK = 1;
f.close();
}
}
}
if (calDataOK && !REPEAT_CAL) {
// calibration data valid
tft.setTouch(calData);
} else {
// data not valid so recalibrate
tft.fillScreen(TFT_BLACK);
tft.setCursor(20, 0);
tft.setTextFont(2);
tft.setTextSize(1);
tft.setTextColor(TFT_WHITE, TFT_BLACK);
tft.println("Touch corners as indicated");
tft.setTextFont(1);
tft.println();
if (REPEAT_CAL) {
tft.setTextColor(TFT_RED, TFT_BLACK);
tft.println("Set REPEAT_CAL to false to stop this running again!");
}
tft.calibrateTouch(calData, TFT_MAGENTA, TFT_BLACK, 15);
tft.setTextColor(TFT_GREEN, TFT_BLACK);
tft.println("Calibration complete!");
// store data
File f = SPIFFS.open(CALIBRATION_FILE, "w");
if (f) {
f.write((const unsigned char *)calData, 14);
f.close();
}
}
}
//------------------------------------------------------------------------------------------
// Print something in the mini status bar
void status(const char *msg) {
tft.setTextPadding(240);
//tft.setCursor(STATUS_X, STATUS_Y);
tft.setTextColor(TFT_WHITE, TFT_DARKGREY);
tft.setTextFont(0);
tft.setTextDatum(TC_DATUM);
tft.setTextSize(1);
tft.drawString(msg, STATUS_X, STATUS_Y);
}
//------------------------------------------------------------------------------------------
One of the benefits of using TFT_eSPI is having the ability to calibrate your display and having that as a part of your workflow. This does require SPIFFS to store this information, so having something like the esp32 family is a well-suited library for most of your needs.

XPT2046_Touchscreen
Another library that works with this particular touchscreen is XPT2046_Touchscreen.
We are using the following libraries:
For information on how to install the libraries above please visist https://www.arduino.cc/en/guide/libraries.
We are going to be using a sketch I wrote for https://www.gabrielcsapo.com/arduino-esp32-c3-32s-ili9341-with-touchscreen/. To look at the most up-to-date sketch you can check it out here.
#include "Adafruit_GFX.h"
#include "Adafruit_ILI9341.h"
#include <XPT2046_Touchscreen.h>
#include <SPI.h>
#define SCLK_PIN 12
#define MISO_PIN 13
#define MOSI_PIN 11
#define TOUCH_CS 34
#define TFT_DC 14
#define TFT_CS 10
#define TFT_RST 15
XPT2046_Touchscreen ts(TOUCH_CS);
Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_RST);
void setup() {
Serial.begin(38400);
SPI.begin( SCLK_PIN, MISO_PIN, MOSI_PIN );
SPI.setFrequency( 40000000 );
tft.begin(4000000);
tft.setRotation(1);
tft.fillScreen(ILI9341_BLACK);
ts.begin();
ts.setRotation(1);
while (!Serial && (millis() <= 1000));
}
boolean wastouched = true;
void loop() {
boolean istouched = ts.touched();
if (istouched) {
TS_Point p = ts.getPoint();
if (!wastouched) {
tft.fillScreen(ILI9341_BLACK);
tft.setTextColor(ILI9341_YELLOW);
tft.setCursor(60, 80);
tft.print("Touch");
}
tft.fillRect(100, 150, 140, 60, ILI9341_BLACK);
tft.setTextColor(ILI9341_GREEN);
tft.setCursor(100, 150);
tft.print("X = ");
tft.print(p.x);
tft.setCursor(100, 180);
tft.print("Y = ");
tft.print(p.y);
Serial.print(", x = ");
Serial.print(p.x);
Serial.print(", y = ");
Serial.println(p.y);
} else {
if (wastouched) {
tft.fillScreen(ILI9341_BLACK);
tft.setTextColor(ILI9341_RED);
tft.setCursor(120, 50);
tft.print("No");
tft.setCursor(80, 120);
tft.print("Touch");
}
Serial.println("no touch");
}
wastouched = istouched;
delay(100);
}

Conclusion
Picking the right library for your needs is important. There are considerations to be made between XPT2046_Touchscreen and TFT_eSPI such as compatibility and required space to run on your device. I have yet to use either in any real-life application other than some of the two examples provided, when I do I will put my findings here.
If you have any questions or want to see more examples in these articles, please comment below or create an issue at https://github.com/gabrielcsapo/gabrielcsapo.com.