ESP32 HMI 2.8-inch Arduino Tutorial¶

#include <lvgl.h>
#include <TFT_eSPI.h> //screen driver library
#include <Arduino.h>
#include <Crowbits_DHT20.h> //Temperature and humidity sensor library

//UI
#include "ui.h"

/* Display Refresh */
/*The function of this code is to use the LCD object to perform the display refresh operation based on the given refresh area and color data, and notify the display driver to complete the refresh operation through the LVGL library. w * h indicates the number of color data, and true indicates that the color data written is 16 bits.*/
void my_disp_flush( lv_disp_drv_t *disp, const lv_area_t *area, lv_color_t *color_p )
{
  uint32_t w = ( area->x2 - area->x1 + 1 );
  uint32_t h = ( area->y2 - area->y1 + 1 );

  lcd.startWrite();
  lcd.setAddrWindow( area->x1, area->y1, w, h );
  lcd.pushColors( ( uint16_t * )&color_p->full, w * h, true );
  lcd.endWrite();

  lv_disp_flush_ready( disp );
}

/*Read Touchpad*/

/*The function of this code is to read the input status and coordinate information of the touch screen and store the results in the specified data structure. If the touch screen is touched, the coordinate information of the touch screen will also be printed to the serial monitor.
The number 600 represents the timeout in milliseconds, which is the maximum amount of time to wait while waiting for touch screen input.
When the lcd.getTouch function is called, it will try to read the input status and coordinate information of the touch screen. If the input is successfully read within 600 milliseconds, the function will return true, indicating that the touch screen was touched. If no input is read within 600 milliseconds, the function will return false, indicating that the touch screen was not touched.
This timeout can be adjusted as needed. A shorter timeout may prevent all coordinate points from being accurately captured when swiping quickly on the touch screen, while a longer timeout may increase response time. This timeout value can be adjusted appropriately according to specific application scenarios and requirements.*/

uint16_t touchX, touchY;

void my_touchpad_read( lv_indev_drv_t * indev_driver, lv_indev_data_t * data )
{
  bool touched = lcd.getTouch( &touchX, &touchY, 600);
  if ( !touched )
  {
    data->state = LV_INDEV_STATE_REL;
  }
  else
  {
    data->state = LV_INDEV_STATE_PR;

    /*Setting the coordinates*/
    data->point.x = touchX;
    data->point.y = touchY;

    Serial.print( "Data x " );
    Serial.println( touchX );

    Serial.print( "Data y " );
    Serial.println( touchY );
  }
}


/*Clear the buffer array. The purpose of this function is to clear the received data in the buffer array so that new data can be received again.*/
unsigned char buffer[256]; // buffer array for data recieve over serial port
int count = 0;   // counter for buffer array
void clearBufferArray()              // function to clear buffer array
{
  for (int i = 0; i < count; i++)
  {
    buffer[i] = NULL; // clear all index of array with command NULL
  }
}

  //Serial port initialization
  Serial.begin( 115200 ); /*Initializing the Serial Port*/
  Serial2.begin( 9600 ); /*Initialize Serial Port 2*/

  //LED IO Pins
  pinMode(25, OUTPUT);
  digitalWrite(25, LOW);

 //DHT20 pin setting and initialization. DHT20 use the I2C interface
  Wire.begin(22, 21);
  dht20.begin();

 //LVGL initialization
  lv_init();


  lcd.begin();
  lcd.fillScreen(TFT_BLACK);
  delay(300);


  //Backlight Pins
  pinMode(27, OUTPUT);
  digitalWrite(27, HIGH);
  lcd.setRotation(1);



/*Screen display initialization, initialize the drawing buffer by calling the lv_disp_draw_buf_init function. This function accepts three parameters: &draw_buf is a pointer to the lv_disp_draw_buf_t structure, buf1 is the buffer used to store pixel data, and the last parameter is NULL to indicate that no additional buffer is used. The buffer size is calculated as screenWidth * screenHeight / 8 and associated with the draw buffer structure.*/
  lv_disp_draw_buf_init( &draw_buf, buf1, NULL, screenWidth * screenHeight / 8 );

  /*Initializing the display*/
  static lv_disp_drv_t disp_drv;/*A static variable disp_drv of type lv_disp_drv_t is defined, which is used to store related configuration and information of the display device driver*/
  lv_disp_drv_init( &disp_drv );
  /*Change the following line to display resolution*/
  disp_drv.hor_res = screenWidth;
  disp_drv.ver_res = screenHeight;
  disp_drv.flush_cb = my_disp_flush;
  disp_drv.draw_buf = &draw_buf;
  lv_disp_drv_register( &disp_drv );

/*Initialize the (virtual) input device driver. The function of this code is to initialize a virtual input device driver and associate it with the LVGL framework in order to handle the interaction of the input device. Among them, by setting the input device type, defining the read callback function and other steps, the necessary configuration and functions are provided for the input device driver*/
  /*Initialize the (virtual) input device driver*/
  static lv_indev_drv_t indev_drv;//Define the input device driver structure

  lv_indev_drv_init( &indev_drv );//Initialize the input device driver

  indev_drv.type = LV_INDEV_TYPE_POINTER;//Setting the input device type

  indev_drv.read_cb = my_touchpad_read;//Define the read callback function

  lv_indev_drv_register( &indev_drv );//Registering Input Device Drivers


//UI initialization
  ui_init();
}

void loop()
{

/*Obtain the temperature and humidity data and use a char array to store it. Use two integer variables a and b to store the obtained temperature and humidity*/
  char DHT_buffer[6];
  int a = (int)dht20.getTemperature();
  int b = (int)dht20.getHumidity();

//Store the value in an array through conversion and display it on the label
  snprintf(DHT_buffer, sizeof(DHT_buffer), "%d", a);
  lv_label_set_text(ui_Label1, DHT_buffer);
  snprintf(DHT_buffer, sizeof(DHT_buffer), "%d", b);
  lv_label_set_text(ui_Label2, DHT_buffer);

/*Judge the value of the LED. In the ui.c program, press the "ON" button to set the LED to 1 and control the LED light to turn on*/
  if(led == 1)
  digitalWrite(25, HIGH);

//*In the ui.c program, press the "OFF" button to set the LED to 0. At this time, the LED light is controlled to be turned off*/
  if(led == 0)
  digitalWrite(25, LOW);

  lv_timer_handler(); /* let the GUI do its work */
  delay( 10 );
}

#include <lvgl.h>
#include <TFT_eSPI.h>
#include <demos/lv_demos.h>
#include<Arduino.h>
#include <Crowbits_DHT20.h>

//UI
#include "ui.h"
int led;

/*Changing the screen resolution*/
static const uint16_t screenWidth  = 320;
static const uint16_t screenHeight = 240;

static lv_disp_draw_buf_t draw_buf;
static lv_color_t buf1[ screenWidth * screenHeight / 8 ];

TFT_eSPI lcd = TFT_eSPI(); /* TFT Example */
// Initialize DHT20 sensor
Crowbits_DHT20 dht20;
uint16_t calData[5] = { 189, 3416, 359, 3439, 1 };

/* Display Refresh */
void my_disp_flush( lv_disp_drv_t *disp, const lv_area_t *area, lv_color_t *color_p )
{
  uint32_t w = ( area->x2 - area->x1 + 1 );
  uint32_t h = ( area->y2 - area->y1 + 1 );

  lcd.startWrite();
  lcd.setAddrWindow( area->x1, area->y1, w, h );
  lcd.pushColors( ( uint16_t * )&color_p->full, w * h, true );
  lcd.endWrite();

  lv_disp_flush_ready( disp );
}

uint16_t touchX, touchY;
/*Read Touchpad*/
void my_touchpad_read( lv_indev_drv_t * indev_driver, lv_indev_data_t * data )
{
  bool touched = lcd.getTouch( &touchX, &touchY, 600);
  if ( !touched )
  {
    data->state = LV_INDEV_STATE_REL;
  }
  else
  {
    data->state = LV_INDEV_STATE_PR;

    /*Setting the coordinates*/
    data->point.x = touchX;
    data->point.y = touchY;

    Serial.print( "Data x " );
    Serial.println( touchX );

    Serial.print( "Data y " );
    Serial.println( touchY );
  }
}

void setup()
{
  Serial.begin( 115200 ); /*Initializing the Serial Port*/
  Serial2.begin( 9600 ); /*Initialize Serial Port 2*/

  //IO Port Pins
  pinMode(25, OUTPUT);
  digitalWrite(25, HIGH);

  Wire.begin(22, 21);
  dht20.begin();

  lv_init();

  lcd.begin();
  lcd.fillScreen(TFT_BLACK);
  delay(300);
  lcd.setTouch( calData );
  //Backlight Pins
  pinMode(27, OUTPUT);
  digitalWrite(27, HIGH);
  lcd.setRotation(1);

  lv_disp_draw_buf_init( &draw_buf, buf1, NULL, screenWidth * screenHeight / 8 );

  /*Initializing the display*/
  static lv_disp_drv_t disp_drv;
  lv_disp_drv_init( &disp_drv );
  /*Change the following line to display resolution*/
  disp_drv.hor_res = screenWidth;
  disp_drv.ver_res = screenHeight;
  disp_drv.flush_cb = my_disp_flush;
  disp_drv.draw_buf = &draw_buf;
  lv_disp_drv_register( &disp_drv );

  /*Initialize the (virtual) input device driver*/
  static lv_indev_drv_t indev_drv;
  lv_indev_drv_init( &indev_drv );
  indev_drv.type = LV_INDEV_TYPE_POINTER;
  indev_drv.read_cb = my_touchpad_read;
  lv_indev_drv_register( &indev_drv );

  ui_init();
}

void loop()
{
  Serial.print(led);
  char DHT_buffer[6];
  int a = (int)dht20.getTemperature();
  int b = (int)dht20.getHumidity();
  snprintf(DHT_buffer, sizeof(DHT_buffer), "%d", a);
  lv_label_set_text(ui_Label1, DHT_buffer);
  snprintf(DHT_buffer, sizeof(DHT_buffer), "%d", b);
  lv_label_set_text(ui_Label2, DHT_buffer);
  if(led == 1)

  digitalWrite(25, HIGH);
  if(led == 0)
  digitalWrite(25, LOW);
  lv_timer_handler(); /* let the GUI do its work */
  delay( 10 );
}

#define D_PIN 25

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pinMode(D_PIN, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(D_PIN, HIGH);
  delay(500);
  digitalWrite(D_PIN, LOW);
  delay(500);
}

#include <U8g2lib.h>
#include <Wire.h>
#define I2C_SDA 22
#define I2C_SCL 21
U8G2_SSD1306_128X64_NONAME_F_SW_I2C u8g2(U8G2_R0, /*clock=*/I2C_SCL, /*data=*/I2C_SDA, /*reset=*/U8X8_PIN_NONE);


void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  //OLED
  u8g2.begin();
  u8g2.enableUTF8Print();        // enable UTF8 support for the Arduino print() function
  u8g2.setFont(u8g2_font_ncenB14_tr);
  u8g2.setFontDirection(0);
  for (int i = 128; i > -78; i -= 20)
  {
    u8g2.firstPage();
    do {
      u8g2.drawStr(i, 25, "ELECROW");
      delay(2);
    } while ( u8g2.nextPage() );
  } 
}

void loop() {

}

#include "MusicDefinitions.h"
#include "SoundData.h"
#include "XT_DAC_Audio.h"


//SPEAK
// Data for the melody. Note followed by optional change in playing length in 1/4 beats. See documentation for more details
int8_t PROGMEM TwinkleTwinkle[] = {
  NOTE_C5, NOTE_C5, NOTE_G5, NOTE_G5, NOTE_A5, NOTE_A5, NOTE_G5, BEAT_2,
  NOTE_F5, NOTE_F5, NOTE_E5, NOTE_E5, NOTE_D5, NOTE_D5, NOTE_C5, BEAT_2,
  NOTE_G5, NOTE_G5, NOTE_F5, NOTE_F5, NOTE_E5, NOTE_E5, NOTE_D5, BEAT_2,
  NOTE_G5, NOTE_G5, NOTE_F5, NOTE_F5, NOTE_E5, NOTE_E5, NOTE_D5, BEAT_2,
  NOTE_C5, NOTE_C5, NOTE_G5, NOTE_G5, NOTE_A5, NOTE_A5, NOTE_G5, BEAT_2,
  NOTE_F5, NOTE_F5, NOTE_E5, NOTE_E5, NOTE_D5, NOTE_D5, NOTE_C5, BEAT_4,
  NOTE_SILENCE, BEAT_5, SCORE_END
};
XT_DAC_Audio_Class DacAudio(26, 0);         // Create the main player class object. Use GPIO 25, one of the 2 DAC pins and timer 0
XT_Wav_Class ForceWithYou(Force);           // create WAV object and pass in the WAV data
XT_MusicScore_Class Music(TwinkleTwinkle, TEMPO_ALLEGRO, INSTRUMENT_PIANO); // The music score object, pass in the Music data
XT_Sequence_Class Sequence;                // The sequence object, you add your sounds above to this object (see setup below)

void setup() {
  // put your setup code here, to run once:
  Serial.begin( 9600 ); 
  Sequence.AddPlayItem(&ForceWithYou);      // Add the first sound item, this will play first
  Sequence.AddPlayItem(&Music);             // Add the music score, this will play after the first item
  DacAudio.Play(&Sequence);                 // Play the sequence, will play just the once and then stop
}

void loop() {
  // put your main code here, to run repeatedly:
  DacAudio.FillBuffer();//Play
  //  DacAudio.StopAllSounds(); //Stop Playing
}

#include <Wire.h>
#include <SPI.h>
#include <SD.h>
#include <FS.h>

#define SD_MOSI 23
#define SD_MISO 19
#define SD_SCK 18
#define SD_CS 5
void setup() {
  // put your setup code here, to run once:
  Serial.begin( 9600 ); /*初始化串口*/
  //SD卡
  SPI.begin(SD_SCK, SD_MISO, SD_MOSI);
  delay(100);
  if (SD_init() == 1)
  {
    Serial.println("Card Mount Failed");
  }
  else
    Serial.println("initialize SD Card successfully");
}

void loop() {
  // put your main code here, to run repeatedly:

}

//SD卡初始化
int SD_init()
{

  if (!SD.begin(SD_CS))
  {
    Serial.println("Card Mount Failed");
    return 1;
  }
  uint8_t cardType = SD.cardType();

  if (cardType == CARD_NONE)
  {
    Serial.println("No TF card attached");
    return 1;
  }

  uint64_t cardSize = SD.cardSize() / (1024 * 1024);
  Serial.printf("TF Card Size: %lluMB\n", cardSize);
  listDir(SD, "/", 2);

  //  listDir(SD, "/", 0);
  //  createDir(SD, "/mydir");
  //  listDir(SD, "/", 0);
  //  removeDir(SD, "/mydir");
  //  listDir(SD, "/", 2);
  //  writeFile(SD, "/hello.txt", "Hello ");
  //  appendFile(SD, "/hello.txt", "World!\n");
  //  readFile(SD, "/hello.txt");
  //  Serial.printf("Total space: %lluMB\n", SD.totalBytes() / (1024 * 1024));
  //  Serial.printf("Used space: %lluMB\n", SD.usedBytes() / (1024 * 1024));
  //  Serial.println("SD init over.");

  return 0;
}

//遍历SD卡目录
void listDir(fs::FS & fs, const char *dirname, uint8_t levels)
{
  //  Serial.printf("Listing directory: %s\n", dirname);

  File root = fs.open(dirname);
  if (!root)
  {
    //Serial.println("Failed to open directory");
    return;
  }
  if (!root.isDirectory())
  {
    Serial.println("Not a directory");
    return;
  }

  File file = root.openNextFile();
//  i = 0;
  while (file)
  {
    if (file.isDirectory())
    {
      //      Serial.print("  DIR : ");
      //      Serial.println(file.name());
      if (levels)
      {
        listDir(fs, file.name(), levels - 1);
      }
    }
    else
    {
      Serial.print("FILE: ");
      Serial.print(file.name());
//      lcd.setCursor(0, 2 * i);
//      lcd.printf("FILE:%s", file.name());

      Serial.print("SIZE: ");
      Serial.println(file.size());
//      lcd.setCursor(180, 2 * i);
//      lcd.printf("SIZE:%d", file.size());
//      i += 16;
    }

    file = root.openNextFile();
  }
}

#include <TFT_eSPI.h>
TFT_eSPI lcd = TFT_eSPI();
uint16_t touchX, touchY;
uint16_t calData[5] = { 189, 3416, 359, 3439, 1 };

void setup() {
  // put your setup code here, to run once:
  Serial.begin( 9600 ); /*Initialize serial port*/
  //LCD Initialize
  lcd.begin(); 
  lcd.setRotation(1); /* Rotate */
  //Calibration mode. One is four-corner positioning, and the other is direct positioning by directly inputting analog values.
  //Screen calibration
//  touch_calibrate();
  lcd.setTouch(calData);

  /*Initialization*/
}

void loop() {
  // put your main code here, to run repeatedly:
  bool touched = lcd.getTouch( &touchX, &touchY, 600);
  if ( touched )
  {
    Serial.print( "Data x " );
    Serial.println( touchX );

    Serial.print( "Data y " );
    Serial.println( touchY );
  }
}

void touch_calibrate()
{
  uint16_t calData[5];
  uint8_t calDataOK = 0;
  Serial.println("Touch-screen calibration");

  //calibration
  Serial.println("Please touch the corners as directed");

 // lv_timer_handler();
  lcd.calibrateTouch(calData, TFT_MAGENTA, TFT_BLACK, 15);
  Serial.println("calibrateTouch(calData, TFT_MAGENTA, TFT_BLACK, 15)");
  Serial.println(); Serial.println();
  Serial.println("//Use this calibration code in setup():");
  Serial.print("uint16_t calData[5] = ");
  Serial.print("{ ");

  for (uint8_t i = 0; i < 5; i++)
  {
    Serial.print(calData[i]);
    if (i < 4) Serial.print(", ");
  }

  Serial.println(" };");
  Serial.print("  tft.setTouch(calData);");
  Serial.println(); Serial.println();


}

#include "BLEDevice.h"              //BLE drive library
#include "BLEServer.h"              //BLE server library
#include "BLEUtils.h"               //BLE Utility library
#include "BLE2902.h"                //Feature Add Descriptor Library
#include <BLECharacteristic.h>      //BLE Feature function library
BLEAdvertising* pAdvertising = NULL;
BLEServer* pServer = NULL;
BLEService *pService = NULL;
BLECharacteristic* pCharacteristic = NULL;
#define bleServerName "ESP32SPI-BLE"  //BLE Server name
#define SERVICE_UUID "6479571c-2e6d-4b34-abe9-c35116712345"  //Server UUID
#define CHARACTERISTIC_UUID "826f072d-f87c-4ae6-a416-6ffdcaa02d73"


bool connected_state = false;   //Create device connection identifier

class MyServerCallbacks: public BLEServerCallbacks  //Create connection and disconnection calling classes
{
    void onConnect(BLEServer *pServer)//Start connecting function
    {
      connected_state = true;   //Device is connected correctly
    }
    void onDisconnect(BLEServer *pServer)//disconnect function
    {
      connected_state = false;  //Device connection error
    }

};
void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  //BLE
  BLEDevice::init(bleServerName);  //Create BLE and set name
  pServer = BLEDevice::createServer();  //Create BLE server
  pServer->setCallbacks(new MyServerCallbacks());  //Set up connection and disconnection calling classes
  pService = pServer->createService(SERVICE_UUID); //Create BLE service

  pCharacteristic = pService->createCharacteristic(  //Create ble feature（Characterristic_UUID）
                      CHARACTERISTIC_UUID,
                      BLECharacteristic::PROPERTY_READ | BLECharacteristic::PROPERTY_WRITE | BLECharacteristic::PROPERTY_NOTIFY);
  pCharacteristic->setValue("ELECROW");
  //start broadcast
  pAdvertising = BLEDevice::getAdvertising();  //A bleadvertising class pointer padvertising is defined, which points to bledevice:: getadvertising()
  pAdvertising->addServiceUUID(SERVICE_UUID);
  pAdvertising->start();  //Start broadcasting
  pService->start();
  //  pAdvertising->stop();  //Stop broadcasting
  //  pService->stop();      //Stop service
}

void loop() {

}

#include <WiFi.h>

const char *ssid = "elecrow888"; //Change to your SSID
const char *password = "elecrow2014"; //Change to your password
void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  WiFi.begin(ssid, password);
  WiFi.setAutoReconnect(true);//Set up automatic reconnection
  while (WiFi.status() != WL_CONNECTED) {
    delay(100);
    Serial.println("connecting");
  }
  Serial.println("WiFi is connected.");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
//  WiFi.disconnect();
}

void loop() {

}

//at 9600 bps 8-N-1

#include <SoftwareSerial.h>

SoftwareSerial SoftSerial(6, 7);
unsigned char buffer[256]; // buffer array for data recieve over serial port
int count=0;     // counter for buffer array 
void setup()
{
  SoftSerial.begin(9600);               // the SoftSerial baud rate   
  Serial.begin(9600);             // the Serial port of Arduino baud rate.

}

void loop()
{
  if (SoftSerial.available())              // if date is comming from softwareserial port ==> data is comming from SoftSerial shield
  {
    while(SoftSerial.available())          // reading data into char array 
    {
      buffer[count++]=SoftSerial.read();     // writing data into array
      if(count == 256)break;
  }
    Serial.write(buffer,count);            // if no data transmission ends, write buffer to hardware serial port
    clearBufferArray();              // call clearBufferArray function to clear the storaged data from the array
    count = 0;                       // set counter of while loop to zero


  }
  if (Serial.available())            // if data is available on hardwareserial port ==> data is comming from PC or notebook
    SoftSerial.write(Serial.read());       // write it to the SoftSerial shield
}
void clearBufferArray()              // function to clear buffer array
{
  for (int i=0; i<count;i++)
    { buffer[i]=NULL;}                  // clear all index of array with command NULL
}