/* Rui Santos & Sara Santos - Random Nerd Tutorials
CYD Project Details: https://RandomNerdTutorials.com/esp32-cyd-lvgl-temperature-ds18b20/
TFT Project Details: https://RandomNerdTutorials.com/esp32-lvgl-ds18b20-tempreature-tft-display/
THIS EXAMPLE WAS TESTED WITH THE FOLLOWING HARDWARE:
1) ESP32-2432S028R 2.8 inch 240×320 also known as the Cheap Yellow Display (CYD): https://makeradvisor.com/tools/cyd-cheap-yellow-display-esp32-2432s028r/
SET UP INSTRUCTIONS: https://RandomNerdTutorials.com/cyd-lvgl/
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/
SET UP INSTRUCTIONS: https://RandomNerdTutorials.com/esp32-tft-lvgl/
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files. The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
*/
// *** YOU MUST USE THE lv_conf.h AND User_Setup.h FILES PROVIDED IN THE NEXT LINKS IN ORDER TO USE THE EXAMPLES FROM RANDOM NERD TUTORIALS: https://RandomNerdTutorials.com/cyd-lvgl/ or https://RandomNerdTutorials.com/esp32-tft-lvgl/
// Install the "lvgl" library version 9.2 by kisvegabor to interface with the TFT Display - https://lvgl.io/ - IMPORTANT: lv_conf.h available on the internet will probably NOT work with the examples available at Random Nerd Tutorials
#include <lvgl.h>
// Install the "TFT_eSPI" library by Bodmer to interface with the TFT Display - https://github.com/Bodmer/TFT_eSPI - IMPORTANT: User_Setup.h available on the internet will probably NOT work with the examples available at Random Nerd Tutorials
#include <TFT_eSPI.h>
// Install OneWire and DallasTemperature libraries
#include <OneWire.h>
#include <DallasTemperature.h>
// GPIO where the DS18B20 is connected to
const int oneWireBus = 27;
// Setup a oneWire instance to communicate with any OneWire devices
OneWire oneWire(oneWireBus);
// Pass our oneWire reference to Dallas Temperature sensor
DallasTemperature sensors(&oneWire);
// SET VARIABLE TO 0 FOR TEMPERATURE IN FAHRENHEIT DEGREES
#define TEMP_CELSIUS 1
#if TEMP_CELSIUS
#define TEMP_ARC_MIN -20
#define TEMP_ARC_MAX 40
#else
#define TEMP_ARC_MIN -4
#define TEMP_ARC_MAX 104
#endif
#define SCREEN_WIDTH 240
#define SCREEN_HEIGHT 320
#define DRAW_BUF_SIZE (SCREEN_WIDTH * SCREEN_HEIGHT / 10 * (LV_COLOR_DEPTH / 8))
uint32_t draw_buf[DRAW_BUF_SIZE / 4];
// If logging is enabled, it will inform the user about what is happening in the library
void log_print(lv_log_level_t level, const char * buf) {
LV_UNUSED(level);
Serial.println(buf);
Serial.flush();
}
lv_obj_t * arc;
// Set the temperature value in the arc and text label
static void set_temp(void * text_label_temp_value, int32_t v) {
sensors.requestTemperatures();
// Get the latest temperature reading in Celsius or Fahrenheit
#if TEMP_CELSIUS
float ds18b20_temp = sensors.getTempCByIndex(0);
if(ds18b20_temp <= 10.0) {
lv_obj_set_style_text_color((lv_obj_t*) text_label_temp_value, lv_palette_main(LV_PALETTE_BLUE), 0);
}
else if (ds18b20_temp > 10.0 && ds18b20_temp <= 29.0) {
lv_obj_set_style_text_color((lv_obj_t*) text_label_temp_value, lv_palette_main(LV_PALETTE_GREEN), 0);
}
else {
lv_obj_set_style_text_color((lv_obj_t*) text_label_temp_value, lv_palette_main(LV_PALETTE_RED), 0);
}
const char degree_symbol[] = "\u00B0C";
#else
float ds18b20_temp = sensors.getTempFByIndex(0);
if(ds18b20_temp <= 50.0) {
lv_obj_set_style_text_color((lv_obj_t*) text_label_temp_value, lv_palette_main(LV_PALETTE_BLUE), 0);
}
else if (ds18b20_temp > 50.0 && ds18b20_temp <= 84.2) {
lv_obj_set_style_text_color((lv_obj_t*) text_label_temp_value, lv_palette_main(LV_PALETTE_GREEN), 0);
}
else {
lv_obj_set_style_text_color((lv_obj_t*) text_label_temp_value, lv_palette_main(LV_PALETTE_RED), 0);
}
const char degree_symbol[] = "\u00B0F";
#endif
lv_arc_set_value(arc, map(int(ds18b20_temp), TEMP_ARC_MIN, TEMP_ARC_MAX, 0, 100));
String ds18b20_temp_text = String(ds18b20_temp) + degree_symbol;
lv_label_set_text((lv_obj_t*) text_label_temp_value, ds18b20_temp_text.c_str());
Serial.print("Temperature: ");
Serial.println(ds18b20_temp_text);
}
void lv_create_main_gui(void) {
// Create an Arc
arc = lv_arc_create(lv_screen_active());
lv_obj_set_size(arc, 210, 210);
lv_arc_set_rotation(arc, 135);
lv_arc_set_bg_angles(arc, 0, 270);
lv_obj_set_style_arc_color(arc, lv_color_hex(0x666666), LV_PART_INDICATOR);
lv_obj_set_style_bg_color(arc, lv_color_hex(0x333333), LV_PART_KNOB);
lv_obj_align(arc, LV_ALIGN_CENTER, 0, 10);
// Create a text label in font size 32 to display the latest temperature reading
lv_obj_t * text_label_temp_value = lv_label_create(lv_screen_active());
lv_label_set_text(text_label_temp_value, "--.--");
lv_obj_align(text_label_temp_value, LV_ALIGN_CENTER, 0, 10);
static lv_style_t style_temp;
lv_style_init(&style_temp);
lv_style_set_text_font(&style_temp, &lv_font_montserrat_32);
lv_obj_add_style(text_label_temp_value, &style_temp, 0);
// Create an animation to update with the latest temperature value every 10 seconds
lv_anim_t a_temp;
lv_anim_init(&a_temp);
lv_anim_set_exec_cb(&a_temp, set_temp);
lv_anim_set_duration(&a_temp, 1000000);
lv_anim_set_playback_duration(&a_temp, 1000000);
lv_anim_set_var(&a_temp, text_label_temp_value);
lv_anim_set_values(&a_temp, 0, 100);
lv_anim_set_repeat_count(&a_temp, LV_ANIM_REPEAT_INFINITE);
lv_anim_start(&a_temp);
}
void setup() {
String LVGL_Arduino = String("LVGL Library Version: ") + lv_version_major() + "." + lv_version_minor() + "." + lv_version_patch();
Serial.begin(115200);
Serial.println(LVGL_Arduino);
// Start the DS18B20 sensor
sensors.begin();
// Start LVGL
lv_init();
// Register print function for debugging
lv_log_register_print_cb(log_print);
// Create a display object
lv_display_t * disp;
// Initialize the TFT display using the TFT_eSPI library
disp = lv_tft_espi_create(SCREEN_WIDTH, SCREEN_HEIGHT, draw_buf, sizeof(draw_buf));
lv_display_set_rotation(disp, LV_DISPLAY_ROTATION_270);
// Function to draw the GUI
lv_create_main_gui();
}
void loop() {
lv_task_handler(); // let the GUI do its work
lv_tick_inc(5); // tell LVGL how much time has passed
delay(5); // let this time pass
}
