![\"ESP32](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2025\/06\/CYD-with-MicroPython-Receive-Data-From-Multiple-Boards.jpg?resize=1200%2C675&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\nNew to the ESP32 Cheap Yellow Display?<\/strong> Start here: Getting Started with ESP32 Cheap Yellow Display Board \u2013 CYD (ESP32-2432S028R)<\/a>.<\/p>\n\n\n\n Here’s an overview of how this project works.<\/p>\n\n\n New to ESP-NOW communication protocol?<\/strong> Get started here: Getting Started with ESP-NOW (ESP32 with Arduino IDE)<\/a>.<\/p>\n\n\n\n Before proceeding, make sure you follow the next prerequisites. You must follow all steps, otherwise, your project will not work.<\/strong><\/p>\n\n\n\n For this project, you need the following parts:<\/p>\n\n\n\n You can use the preceding links or go directly to MakerAdvisor.com\/tools<\/a> to find all the parts for your projects at the best price!<\/p> We’ll program the ESP32 using Arduino IDE. Make sure you have the ESP32 boards installed. Follow the next tutorial:<\/p>\n\n\n\n The ESP32-2432S028R<\/a> development board has become known in the maker community as the \u201cCheap Yellow Display<\/em>\u201d or CYD for short. This development board, whose main chip is an ESP32-WROOM-32 module, comes with a 2.8-inch TFT touchscreen LCD, a microSD card interface, an RGB LED, and all the required circuitry to program and apply power to the board.<\/p>\n\n\n If this is your first time using the ESP32 Cheap Yellow Display, make sure to follow our getting started guide:<\/p>\n\n\n\n LVGL<\/a> (Light and Versatile Graphics Library) is a free and open-source graphics library that provides a wide range of easy-to-use graphical elements for your microcontroller projects that require a graphical user interface (GUI).<\/p>\n\n\n Follow the next tutorial to install and configure the required libraries to use LVGL for the ESP32 Cheap Yellow Display using Arduino IDE.<\/p>\n\n\n\n For this project, we’ll use the Adafruit BME280 library to get data from the BME280 on the other ESP32 boards. In the Arduino IDE, go to Sketch <\/strong>> Include Library<\/strong> > Manage Libraries<\/strong>. Search for Adafruit BME280 Library<\/em> in the search box and install the library. Also, install any dependencies that are currently not installed (usually the Adafruit Bus IO and the Adafruit Unified Sensor libraries).<\/p>\n\n\n First, you need to know the MAC address of the CYD board so that the sender boards can send messages to it.<\/p>\n\n\n Upload the following code to the CYD Board.<\/p>\n\n\n View raw code<\/a><\/p>\n\n\n\n After uploading, open the Serial Monitor at a baud rate of 115200. Press the onboard RST button. The board’s MAC Address will be printed in the Serial Monitor.<\/p>\n\n\n For this tutorial, we’ll send data to the CYD from two different boards. You can modify this project to display data from more boards. <\/p>\n\n\n\n Each board will be identified by an ID (a number that we’ll attribute to each board):<\/p>\n\n\n\n Each sender board will send environmental data from a BME280 sensor. Wire a BME280 sensor to each of your boards. We’ll use the ESP32 default I2C pins.<\/p>\n\n\n\n Learn more about I2C with the ESP32: ESP32 I2C Communication: Set Pins, Multiple Bus Interfaces and Peripherals (Arduino IDE)<\/a>.<\/p>\n\n\n Not familiar with the BME280 with the ESP32? Read this tutorial: ESP32 with BME280 Sensor using Arduino IDE (Pressure, Temperature, Humidity)<\/strong><\/a>.<\/p>\n\n\n\n If you’re using a different board model, the default I2C pins migh different.<\/p>\n\n\n\n The following code reads the data from the BME280 sensor and sends it via ESP-NOW to the CYD board. Don’t forget to modify the code with your CYD board’s MAC address. Additionally, don’t forget to change the board ID for each of your boards.<\/p>\n\n\n View raw code<\/a><\/p>\n\n\n\n Let’s take a look at how the code works. If you’re new to ESP-NOW, we recommend getting started with this ESP-NOW guide<\/a> to better understand how things work.<\/p>\n\n\n\n Start to include the required libraries for this project. The esp_now<\/span> and WiFi<\/span> are required to use ESP-NOW communication, and the Adafruit_BME280<\/span> and Adafruit_Sensor<\/span> are needed to interface with the BME280 sensor.<\/p>\n\n\n\n Give a unique ID to your board so that the receiver can easily identify it. Here, we’re just numbering the boards, but you can use a different method, like giving them a name, or simply identifying them by the MAC address.<\/p>\n\n\n\n Make sure you give a different ID to each board.<\/p>\n\n\n\n Create an instance of the Adafruit_BME280<\/span> library called bme<\/span> that will be used to interface with the sensor.<\/p>\n\n\n\n Insert your receiver board (the CYD board) MAC address. For example, my CYD board MAC address is 24:dc:c3:49:6a:14<\/span>. I must add it to the code in the following format.<\/p>\n\n\n\n Create a new structure called struct_message<\/span> that will contain all the data you want to send. The id<\/span> is the ID of the board, the temperature<\/span> and humidity<\/span> correspond to the data we get from the BME280 sensor, and the readingId<\/span> is just a number to keep track of the number of readings sent.<\/p>\n\n\n\n Then, we create a new structure variable called myData<\/span> based on the struct_message<\/span> structure.<\/p>\n\n\n\n We create several functions related to the BME280 sensor.<\/p>\n\n\n\n The initBME()<\/span> initializes the BME280 sensor on the ESP32’s default I2C pins.<\/p>\n\n\n\n The readTemperature()<\/span> function returns the current temperature value as a float.<\/p>\n\n\n\n The readHumidity()<\/span> function returns the current humidity value, also as a float.<\/p>\n\n\n\n Create a new global variable of type esp_now_peer_info_t<\/span> called peerInfo<\/span> that will be used later on to save data about ESP-NOW peers.<\/p>\n\n\n\n The onDataSent()<\/span> is a callback function that will be called when we send a message via ESP-NOW. This function will print the sender MAC address and whether the message was successfully delivered or not.<\/p>\n\n\n\n In the setup()<\/span>, initialize the Serial Monitor and the BME280 sensor.<\/p>\n\n\n\n You also need to initialize the Wi-Fi interface to be able to use ESP-NOW.<\/p>\n\n\n\n Initialize ESP-NOW protocol.<\/p>\n\n\n\n Register a callback function that will run when we send data via ESP-NOW.<\/p>\n\n\n\n Register the ESP-NOW peer (the receiver board).<\/p>\n\n\n\n In this example, we won’t encrypt the messages. If you want to learn more about encrypting ESP-NOW messages, you can read this tutorial: ESP32: ESP-NOW Encrypted Messages<\/a>.<\/p>\n\n\n\n Finally, in the loop()<\/span>, every 10 seconds (set previously on the interval<\/span> variable), we get new data and set the myData<\/span> structure values to that new data.<\/p>\n\n\n\n In the end, we use the esp_now_send()<\/span> function to send the data to the peer.<\/p>\n\n\n\n We print the sensor readings and information about the sending process in the Serial Monitor.<\/p>\n\n\n\n After uploading the code to the board, open the Serial Monitor at a baud rate of 115200.<\/p>\n\n\n You’ll see that the board will start sending data via ESP-NOW. At the moment, the delivery is failing because we haven’t prepared the receiver yet\u2014that’s what we’re going to do next.<\/p>\n\n\n\n Don’t forget to upload that code to each board and change the board ID.<\/p>\n\n\n\n The CYD board will act as a ESP-NOW receiver that will get the data from the other two boards.<\/p>\n\n\n\n The data from each board will be displayed on the screen. We’ll create two different tabs: one for each board.<\/p>\n\n\nProject Overview<\/h2>\n\n\n\n
![\"ESP32](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2025\/06\/CYD-Receive-Data-Via-ESP-NOW-Project-Overview-.png?resize=750%2C490&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n\n
Prerequisites<\/h2>\n\n\n\n
1) Parts Required<\/h3>\n\n\n\n
\n
![](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/10\/header-200.png?w=1200&quality=100&strip=all&ssl=1\")
<\/a><\/p>\n\n\n\n2) Install ESP32 Boards in Arduino IDE<\/h3>\n\n\n
![\"Arduino](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2024\/06\/arduino-ide-2.jpg?resize=204%2C204&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n\n
3) Get familiar with the ESP32 Cheap Yellow Display<\/h3>\n\n\n\n
![\"ESP32](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2024\/03\/ESP32-Cheap-Yellow-Display-CYD-Board-ESP32-2432S028R-front.jpg?resize=750%2C421&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n\n
4) Install TFT and LVGL Libraries<\/h3>\n\n\n\n
![\"LVGL](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2024\/08\/LVGL-new-logo.png?resize=622%2C194&quality=100&strip=all&ssl=1\"){kind=logo}
<\/figure><\/div>\n\n\n\n
5) Install BME280 Libraries<\/h3>\n\n\n\n
![\"Installing](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2024\/09\/Installing-Adafruit-BME280-Sensor-Library-Arduino-IDE.png?resize=290%2C305&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\nGetting the CYD Board MAC Address<\/h2>\n\n\n\n
<\/figure><\/div>\n\n\n\/*\n Rui Santos & Sara Santos - Random Nerd Tutorials\n Complete project details at https:\/\/RandomNerdTutorials.com\/get-change-esp32-esp8266-mac-address-arduino\/\n Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files. \n The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.\n*\/\n#include <WiFi.h>\n#include <esp_wifi.h>\n\nvoid readMacAddress(){\n uint8_t baseMac[6];\n esp_err_t ret = esp_wifi_get_mac(WIFI_IF_STA, baseMac);\n if (ret == ESP_OK) {\n Serial.printf("%02x:%02x:%02x:%02x:%02x:%02x\\n",\n baseMac[0], baseMac[1], baseMac[2],\n baseMac[3], baseMac[4], baseMac[5]);\n } else {\n Serial.println("Failed to read MAC address");\n }\n}\n\nvoid setup(){\n Serial.begin(115200);\n\n WiFi.mode(WIFI_STA);\n WiFi.STA.begin();\n\n Serial.print("[DEFAULT] ESP32 Board MAC Address: ");\n readMacAddress();\n}\n \nvoid loop(){\n\n}\n<\/code><\/pre>\n\t![\"Getting](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2025\/06\/ESP32-CYD-Board-Get-Mac-Address.png?resize=674%2C394&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n
\n\n\n\nPreparing the Sender Boards<\/h2>\n\n\n\n
\n
![\"Two](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2025\/06\/Two-ESP32-Boards-with-BME280.jpg?resize=750%2C422&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\nWiring the BME280 Sensor<\/h3>\n\n\n\n
![\"ESP32](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2020\/10\/ESP32-BME280-Sensor-Temperature-Humidity-Pressure-Wiring-Diagram-Circuit_f.png?resize=675%2C670&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\nESP32 ESP-NOW Sender Code<\/h3>\n\n\n\n
\/*********\n Rui Santos & Sara Santos - Random Nerd Tutorials\n Complete project details at https:\/\/RandomNerdTutorials.com\/esp32-cyd-esp-now-receive-data\/\n Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files.\n The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.\n*********\/\n#include <esp_now.h>\n#include <WiFi.h>\n#include <Adafruit_BME280.h>\n#include <Adafruit_Sensor.h>\n\n\/\/ Set your Board ID (ESP32 Sender #1 = BOARD_ID 1, ESP32 Sender #2 = BOARD_ID 2, etc)\n#define BOARD_ID 1\n\nAdafruit_BME280 bme; \n\n\/\/ REPLACE WITH YOUR ESP RECEIVER'S MAC ADDRESS\nuint8_t broadcastAddress[] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};\n\n\/\/ Structure to send data, must match the receiver structure\ntypedef struct struct_message {\n int id;\n float temp;\n float hum;\n int readingId;\n} struct_message;\n\n\/\/ Create a struct_message called myData\nstruct_message myData;\n\nunsigned long previousMillis = 0; \/\/ Stores last time temperature was published\nconst long interval = 10000; \/\/ Interval at which to publish sensor readings\n\nunsigned int readingId = 0;\n\nvoid initBME() {\n if (!bme.begin(0x76)) {\n Serial.println("Could not find a valid BME280 sensor, check wiring!");\n while (1);\n }\n}\n\nfloat readTemperature() {\n float t = bme.readTemperature();\n return t;\n}\n\nfloat readHumidity() {\n float h = bme.readHumidity();\n return h;\n}\n\nesp_now_peer_info_t peerInfo;\n\n\/\/ Callback when data is sent\nvoid OnDataSent(const wifi_tx_info_t* mac_addr, esp_now_send_status_t status) {\n char macStr[18];\n Serial.print("Packet to: ");\n \/\/ Copies the receiver mac address to a string\n snprintf(macStr, sizeof(macStr), "%02x:%02x:%02x:%02x:%02x:%02x",\n mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_addr[4], mac_addr[5]);\n Serial.print(macStr);\n Serial.print(" send status:\\t");\n Serial.println(status == ESP_NOW_SEND_SUCCESS ? "Delivery Success" : "Delivery Fail");\n}\n \nvoid setup() {\n Serial.begin(115200);\n initBME(); \n\n WiFi.mode(WIFI_STA);\n \n if (esp_now_init() != ESP_OK) {\n Serial.println("Error initializing ESP-NOW");\n return;\n }\n \n esp_now_register_send_cb(esp_now_send_cb_t(OnDataSent));\n \n \/\/ Register peer\n peerInfo.channel = 0; \n peerInfo.encrypt = false;\n \/\/ Copy receiver's MAC address to peerInfo\n memcpy(peerInfo.peer_addr, broadcastAddress, 6);\n if (esp_now_add_peer(&peerInfo) != ESP_OK) {\n Serial.println("Failed to add peer");\n return;\n }\n}\n \nvoid loop() {\n unsigned long currentMillis = millis();\n if (currentMillis - previousMillis >= interval) {\n \/\/ Save the last time a new reading was published\n previousMillis = currentMillis;\n \/\/ Set values to send\n myData.id = BOARD_ID;\n myData.temp = readTemperature();\n myData.hum = readHumidity();\n myData.readingId = readingId++;\n \n \/\/ Send data and check for errors\n esp_err_t result = esp_now_send(broadcastAddress, (uint8_t *) &myData, sizeof(myData));\n Serial.print("Sending data (Reading ID: ");\n Serial.print(myData.readingId);\n Serial.print(", Temp: ");\n Serial.print(myData.temp);\n Serial.print("C, Hum: ");\n Serial.print(myData.hum);\n Serial.print("%): ");\n Serial.println(result == ESP_OK ? "Sent" : "Failed to send");\n }\n}\n<\/code><\/pre>\n\tHow Does the Code Work?<\/h3>\n\n\n\n
Including Libraries<\/h4>\n\n\n\n
#include <esp_now.h>\n#include <WiFi.h>\n#include <Adafruit_BME280.h>\n#include <Adafruit_Sensor.h><\/code><\/pre>\n\n\n\nSet Your Board ID<\/h4>\n\n\n\n
\/\/ Set your Board ID (ESP32 Sender #1 = BOARD_ID 1, ESP32 Sender #2 = BOARD_ID 2, etc)\n#define BOARD_ID 2<\/code><\/pre>\n\n\n\nBME280 Instance<\/h4>\n\n\n\n
Adafruit_BME280 bme; <\/code><\/pre>\n\n\n\nThe Receiver Board’s MAC Address<\/h4>\n\n\n\n
\/\/ REPLACE WITH YOUR ESP RECEIVER'S MAC ADDRESS\nuint8_t broadcastAddress[] = {0x24, 0xDC, 0xC3, 0x49, 0x6A, 0x14};<\/code><\/pre>\n\n\n\nCreating a Data Structure<\/h4>\n\n\n\n
typedef struct struct_message {\n int id;\n float temp;\n float hum;\n int readingId;\n} struct_message;<\/code><\/pre>\n\n\n\nstruct_message myData;<\/code><\/pre>\n\n\n\nInitializing and Getting Data from the BME280 Sensor<\/h4>\n\n\n\n
void initBME() {\n if (!bme.begin(0x76)) {\n Serial.println(\"Could not find a valid BME280 sensor, check wiring!\");\n while (1);\n }\n}<\/code><\/pre>\n\n\n\nfloat readTemperature() {\n float t = bme.readTemperature();\n return t;\n}<\/code><\/pre>\n\n\n\nfloat readHumidity() {\n float h = bme.readHumidity();\n return h;\n}<\/code><\/pre>\n\n\n\nPeer Info Variable<\/h4>\n\n\n\n
esp_now_peer_info_t peerInfo;<\/code><\/pre>\n\n\n\nOnDataSent()<\/h4>\n\n\n\n
\/\/ Callback when data is sent\nvoid OnDataSent(const uint8_t *mac_addr, esp_now_send_status_t status) {\n char macStr[18];\n Serial.print(\"Packet to: \");\n \/\/ Copies the receiver mac address to a string\n snprintf(macStr, sizeof(macStr), \"%02x:%02x:%02x:%02x:%02x:%02x\",\n mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_addr[4], mac_addr[5]);\n Serial.print(macStr);\n Serial.print(\" send status:\\t\");\n Serial.println(status == ESP_NOW_SEND_SUCCESS ? \"Delivery Success\" : \"Delivery Fail\");\n}<\/code><\/pre>\n\n\n\nsetup()<\/h4>\n\n\n\n
Serial.begin(115200);\ninitBME();<\/code><\/pre>\n\n\n\nWiFi.mode(WIFI_STA);<\/code><\/pre>\n\n\n\nif (esp_now_init() != ESP_OK) {\n Serial.println(\"Error initializing ESP-NOW\");\n return;\n}<\/code><\/pre>\n\n\n\nesp_now_register_send_cb(OnDataSent);<\/code><\/pre>\n\n\n\n\/\/ Register peer\npeerInfo.channel = 0; \npeerInfo.encrypt = false;\n\/\/ Copy receiver's MAC address to peerInfo\nmemcpy(peerInfo.peer_addr, broadcastAddress, 6);\nif (esp_now_add_peer(&peerInfo) != ESP_OK) {\n Serial.println(\"Failed to add peer\");\n return;\n}<\/code><\/pre>\n\n\n\nloop()<\/h4>\n\n\n\n
void loop() {\n unsigned long currentMillis = millis();\n if (currentMillis - previousMillis >= interval) {\n \/\/ Save the last time a new reading was published\n previousMillis = currentMillis;\n \/\/ Set values to send\n myData.id = BOARD_ID;\n myData.temp = readTemperature();\n myData.hum = readHumidity();\n myData.readingId = readingId++;<\/code><\/pre>\n\n\n\n\/\/ Send data and check for errors\nesp_err_t result = esp_now_send(broadcastAddress, (uint8_t *) &myData, sizeof(myData));<\/code><\/pre>\n\n\n\nesp_err_t result = esp_now_send(broadcastAddress, (uint8_t *) &myData, sizeof(myData));\nSerial.print(\"Sending data (Reading ID: \");\nSerial.print(myData.readingId);\nSerial.print(\", Temp: \");\nSerial.print(myData.temp);\nSerial.print(\"C, Hum: \");\nSerial.print(myData.hum);\nSerial.print(\"%): \");\nSerial.println(result == ESP_OK ? \"Sent\" : \"Failed to send\");<\/code><\/pre>\n\n\n\nTesting the Sender Code<\/h3>\n\n\n\n
![\"Serial](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2025\/06\/ESP32-BME280-ESP-NOW-Sender-Board-Serial-Monitor-Demonstration.png?resize=687%2C381&quality=100&strip=all&ssl=1\")
<\/a><\/figure><\/div>\n\n\nESP32 CYD ESP-NOW Receiver Board<\/h2>\n\n\n\n
![\"ESP32](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2025\/06\/ESP32-CYD-Board-Display-Data-Form-Multiple-Boards-ESP-NOW-1-small.png?resize=750%2C460&quality=100&strip=all&ssl=1\")
<\/figure><\/div><\/div>\n\n\n\n![\"ESP32](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2025\/06\/ESP32-CYD-Board-Display-Data-Form-Multiple-Boards-ESP-NOW-2-small.png?resize=750%2C460&quality=100&strip=all&ssl=1\")
<\/figure><\/div><\/div>\n<\/div>\n\n\n\n\/* Rui Santos & Sara Santos - Random Nerd Tutorials - https:\/\/RandomNerdTutorials.com\/esp32-cyd-esp-now-receive-data\/\n THIS EXAMPLE WAS TESTED WITH THE FOLLOWING HARDWARE:\n 1) ESP32-2432S028R 2.8 inch 240\u00d7320 also known as the Cheap Yellow Display (CYD): https:\/\/makeradvisor.com\/tools\/cyd-cheap-yellow-display-esp32-2432s028r\/\n SET UP INSTRUCTIONS: https:\/\/RandomNerdTutorials.com\/cyd-lvgl\/\n 2) REGULAR ESP32 Dev Board + 2.8 inch 240x320 TFT Display: https:\/\/makeradvisor.com\/tools\/2-8-inch-ili9341-tft-240x320\/ and https:\/\/makeradvisor.com\/tools\/esp32-dev-board-wi-fi-bluetooth\/\n SET UP INSTRUCTIONS: https:\/\/RandomNerdTutorials.com\/esp32-tft-lvgl\/\n Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files.\n The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.\n*\/\n\n\/* Install the "lvgl" library version 9.X by kisvegabor to interface with the TFT Display - https:\/\/lvgl.io\/\n *** IMPORTANT: lv_conf.h available on the internet will probably NOT work with the examples available at Random Nerd Tutorials ***\n *** YOU MUST USE THE lv_conf.h FILE PROVIDED IN THE LINK BELOW IN ORDER TO USE THE EXAMPLES FROM RANDOM NERD TUTORIALS ***\n FULL INSTRUCTIONS AVAILABLE ON HOW CONFIGURE THE LIBRARY: https:\/\/RandomNerdTutorials.com\/cyd-lvgl\/ or https:\/\/RandomNerdTutorials.com\/esp32-tft-lvgl\/ *\/\n#include <lvgl.h>\n\n\/* Install the "TFT_eSPI" library by Bodmer to interface with the TFT Display - https:\/\/github.com\/Bodmer\/TFT_eSPI\n *** IMPORTANT: User_Setup.h available on the internet will probably NOT work with the examples available at Random Nerd Tutorials ***\n *** YOU MUST USE THE User_Setup.h FILE PROVIDED IN THE LINK BELOW IN ORDER TO USE THE EXAMPLES FROM RANDOM NERD TUTORIALS ***\n FULL INSTRUCTIONS AVAILABLE ON HOW CONFIGURE THE LIBRARY: https:\/\/RandomNerdTutorials.com\/cyd-lvgl\/ or https:\/\/RandomNerdTutorials.com\/esp32-tft-lvgl\/ *\/\n#include <TFT_eSPI.h>\n\n\/\/ Install the "XPT2046_Touchscreen" library by Paul Stoffregen to use the Touchscreen - https:\/\/github.com\/PaulStoffregen\/XPT2046_Touchscreen - Note: this library doesn't require further configuration\n#include <XPT2046_Touchscreen.h>\n\n#include <esp_now.h>\n#include <WiFi.h>\n#include <freertos\/queue.h>\n\n\/\/ Touchscreen pins\n#define XPT2046_IRQ 36 \/\/ T_IRQ\n#define XPT2046_MOSI 32 \/\/ T_DIN\n#define XPT2046_MISO 39 \/\/ T_OUT\n#define XPT2046_CLK 25 \/\/ T_CLK\n#define XPT2046_CS 33 \/\/ T_CS\n\nSPIClass touchscreenSPI = SPIClass(VSPI);\nXPT2046_Touchscreen touchscreen(XPT2046_CS, XPT2046_IRQ);\n\n#define SCREEN_WIDTH 240\n#define SCREEN_HEIGHT 320\n\n\/\/ SET VARIABLE TO 0 FOR THE TEMPERATURE DEGREES SYMBOL IN FAHRENHEIT\n#define TEMP_CELSIUS 1 \n\n\/\/ Touchscreen coordinates: (x, y) and pressure (z)\nint x, y, z;\n\n#define DRAW_BUF_SIZE (SCREEN_WIDTH * SCREEN_HEIGHT \/ 10 * (LV_COLOR_DEPTH \/ 8))\nuint32_t draw_buf[DRAW_BUF_SIZE \/ 4];\n\n\/\/ Define a queue handle\nQueueHandle_t esp_now_queue;\n\n\/\/ Structure to receive data, must match the sender structure\ntypedef struct {\n int id;\n float temp;\n float hum;\n int readingId;\n} struct_message;\n\nstatic lv_obj_t * table1;\nstatic lv_obj_t * table2;\n\n\/\/ Callback function executed when data is received\nvoid OnDataRecv(const esp_now_recv_info *recv_info, const uint8_t *incomingData, int len) {\n \/\/ Copy incoming data to myData structure\n struct_message myData;\n memcpy(&myData, incomingData, sizeof(myData));\n xQueueSendFromISR(esp_now_queue, &myData, NULL); \/\/ Send to queue from ISR\n\n \/\/ Get sender's MAC address from recv_info\n const uint8_t *mac_addr = recv_info->src_addr;\n \n \/\/ Convert sender's MAC address to a string for display\n char macStr[18];\n snprintf(macStr, sizeof(macStr), "%02X:%02X:%02X:%02X:%02X:%02X",\n mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_addr[4], mac_addr[5]);\n \n \/\/ Print received data to Serial Monitor\n Serial.println("Received data:");\n Serial.print(" Sender MAC: ");\n Serial.println(macStr);\n Serial.print(" Board ID: ");\n Serial.println(myData.id);\n Serial.print(" Temperature: ");\n Serial.print(myData.temp);\n Serial.println(" \u00b0C");\n Serial.print(" Humidity: ");\n Serial.print(myData.hum);\n Serial.println(" %");\n Serial.print(" Reading ID: ");\n Serial.println(myData.readingId);\n Serial.println("-------------------");\n}\n\n\/\/ If logging is enabled, it will inform the user about what is happening in the library\nvoid log_print(lv_log_level_t level, const char * buf) {\n LV_UNUSED(level);\n Serial.println(buf);\n Serial.flush();\n}\n\n\/\/ Get the Touchscreen data\nvoid touchscreen_read(lv_indev_t * indev, lv_indev_data_t * data) {\n \/\/ Checks if Touchscreen was touched, and prints X, Y and Pressure (Z)\n if(touchscreen.tirqTouched() && touchscreen.touched()) {\n \/\/ Get Touchscreen points\n TS_Point p = touchscreen.getPoint();\n\n \/\/ Advanced Touchscreen calibration, LEARN MORE \u00bb https:\/\/RandomNerdTutorials.com\/touchscreen-calibration\/\n float alpha_x, beta_x, alpha_y, beta_y, delta_x, delta_y;\n\n \/\/ REPLACE WITH YOUR OWN CALIBRATION VALUES \u00bb https:\/\/RandomNerdTutorials.com\/touchscreen-calibration\/\n alpha_x = -0.000;\n beta_x = 0.090;\n delta_x = -33.771;\n alpha_y = 0.066;\n beta_y = 0.000;\n delta_y = -14.632;\n\n x = alpha_y * p.x + beta_y * p.y + delta_y;\n \/\/ clamp x between 0 and SCREEN_WIDTH - 1\n x = max(0, x);\n x = min(SCREEN_WIDTH - 1, x);\n\n y = alpha_x * p.x + beta_x * p.y + delta_x;\n \/\/ clamp y between 0 and SCREEN_HEIGHT - 1\n y = max(0, y);\n y = min(SCREEN_HEIGHT - 1, y);\n\n \/\/ Basic Touchscreen calibration points with map function to the correct width and height\n \/\/x = map(p.x, 200, 3700, 1, SCREEN_WIDTH);\n \/\/y = map(p.y, 240, 3800, 1, SCREEN_HEIGHT);\n\n z = p.z;\n\n data->state = LV_INDEV_STATE_PRESSED;\n\n \/\/ Set the coordinates\n data->point.x = x;\n data->point.y = y;\n\n \/\/ Print Touchscreen info about X, Y and Pressure (Z) on the Serial Monitor\n Serial.print("X = ");\n Serial.print(x);\n Serial.print(" | Y = ");\n Serial.print(y);\n Serial.print(" | Pressure = ");\n Serial.print(z);\n Serial.println();\n }\n else {\n data->state = LV_INDEV_STATE_RELEASED;\n }\n}\n\nvoid lv_create_main_gui(void) {\n \/\/ Create a Tab view object\n lv_obj_t * tabview;\n tabview = lv_tabview_create(lv_screen_active());\n lv_tabview_set_tab_bar_size(tabview, 40);\n \n \/\/ Add 3 tabs (the tabs are page (lv_page) and can be scrolled\n lv_obj_t * tab1 = lv_tabview_add_tab(tabview, "BOARD #1");\n lv_obj_t * tab2 = lv_tabview_add_tab(tabview, "BOARD #2");\n\n table1 = lv_table_create(tab1);\n lv_table_set_cell_value(table1, 0, 0, "Temperature");\n lv_table_set_cell_value(table1, 1, 0, "Humidity");\n lv_table_set_cell_value(table1, 2, 0, "Reading ID");\n lv_table_set_cell_value(table1, 0, 1, "--");\n lv_table_set_cell_value(table1, 1, 1, "--");\n lv_table_set_cell_value(table1, 2, 1, "--");\n\n table2 = lv_table_create(tab2);\n lv_table_set_cell_value(table2, 0, 0, "Temperature");\n lv_table_set_cell_value(table2, 1, 0, "Humidity");\n lv_table_set_cell_value(table2, 2, 0, "Reading ID");\n lv_table_set_cell_value(table2, 0, 1, "--");\n lv_table_set_cell_value(table2, 1, 1, "--");\n lv_table_set_cell_value(table2, 2, 1, "--");\n\n \/\/ Center the tables\n lv_obj_center(table1);\n lv_obj_center(table2);\n}\n\nvoid update_table_values(struct_message *myData) {\n #if TEMP_CELSIUS\n const char degree_symbol[] = "\\u00B0C";\n #else\n const char degree_symbol[] = "\\u00B0F";\n #endif\n\n String temp_value = String(myData->temp) + degree_symbol;\n String humi_value = String(myData->hum) + "%";\n\n if(myData->id == 1) {\n lv_table_set_cell_value(table1, 0, 1, temp_value.c_str());\n lv_table_set_cell_value(table1, 1, 1, humi_value.c_str());\n lv_table_set_cell_value(table1, 2, 1, String(myData->readingId).c_str());\n }\n else if(myData->id == 2) {\n lv_table_set_cell_value(table2, 0, 1, temp_value.c_str());\n lv_table_set_cell_value(table2, 1, 1, humi_value.c_str());\n lv_table_set_cell_value(table2, 2, 1, String(myData->readingId).c_str());\n }\n}\n\nvoid setup() {\n String LVGL_Arduino = String("LVGL Library Version: ") + lv_version_major() + "." + lv_version_minor() + "." + lv_version_patch();\n Serial.begin(115200);\n Serial.println(LVGL_Arduino);\n\n \/\/ Set device as a Wi-Fi Station\n WiFi.mode(WIFI_STA);\n\n \/\/ Initialize ESP-NOW\n if (esp_now_init() != ESP_OK) {\n Serial.println("Error initializing ESP-NOW");\n return;\n }\n\n \/\/ Start LVGL\n lv_init();\n \/\/ Register print function for debugging\n lv_log_register_print_cb(log_print);\n\n \/\/ Start the SPI for the touchscreen and init the touchscreen\n touchscreenSPI.begin(XPT2046_CLK, XPT2046_MISO, XPT2046_MOSI, XPT2046_CS);\n touchscreen.begin(touchscreenSPI);\n \/\/ Set the Touchscreen rotation in landscape mode\n \/\/ Note: in some displays, the touchscreen might be upside down, so you might need to set the rotation to 0: touchscreen.setRotation(0);\n touchscreen.setRotation(2);\n\n \/\/ Create a display object\n lv_display_t * disp;\n \/\/ Initialize the TFT display using the TFT_eSPI library\n disp = lv_tft_espi_create(SCREEN_WIDTH, SCREEN_HEIGHT, draw_buf, sizeof(draw_buf));\n lv_display_set_rotation(disp, LV_DISPLAY_ROTATION_270);\n \n \/\/ Initialize an LVGL input device object (Touchscreen)\n lv_indev_t * indev = lv_indev_create();\n lv_indev_set_type(indev, LV_INDEV_TYPE_POINTER);\n \/\/ Set the callback function to read Touchscreen input\n lv_indev_set_read_cb(indev, touchscreen_read);\n\n \/\/ Function to draw the GUI\n lv_create_main_gui();\n\n \/\/ Register callback function to handle received data\n esp_now_register_recv_cb(OnDataRecv);\n \n esp_now_queue = xQueueCreate(10, sizeof(struct_message)); \/\/ Queue for 10 messages\n if (esp_now_queue == NULL) {\n Serial.println("Error creating queue");\n return;\n }\n}\n\nvoid loop() {\n lv_task_handler(); \/\/ let the GUI do its work\n lv_tick_inc(5); \/\/ tell LVGL how much time has passed\n delay(5); \/\/ let this time pass\n \n struct_message myData;\n if (xQueueReceive(esp_now_queue, &myData, 0) == pdTRUE) {\n \/\/ Process and display the data\n update_table_values(&myData);\n }\n}\n<\/code><\/pre>\n\t