ESP32 Weather Station

A beautiful weather display for ESP32 with 2.8" TFT LCD (240x320) using LVGL graphics library.

ESP32 weather station showing real-time weather data for Belgrade

Features

• Real-time weather data from OpenWeatherMap
• Beautiful LVGL-based UI
• Displays:
  • Current temperature
  • Weather description
  • Humidity
  • City name
  • Last update time
• Auto-refresh every 15 minutes
• WiFi connection status

Hardware Requirements

• ESP32 board with WiFi
• 2.8" ILI9341 TFT LCD display (240x320)
• USB cable for programming

Software Requirements

• PlatformIO (VS Code extension recommended)
• OpenWeatherMap API key (free tier)

Setup Instructions

1. Get OpenWeatherMap API Key

1. Go to OpenWeatherMap
2. Sign up for a free account
3. Navigate to API Keys section
4. Copy your API key

2. Configure the Project

Edit include/config.h and update:

#define WIFI_SSID "YOUR_WIFI_SSID"           // Your WiFi network name
#define WIFI_PASSWORD "YOUR_WIFI_PASSWORD"   // Your WiFi password
#define WEATHER_API_KEY "YOUR_API_KEY"       // Your OpenWeatherMap API key
#define WEATHER_CITY "New York"              // Your city name
#define WEATHER_COUNTRY_CODE "US"            // Your country code

3. Install PlatformIO

If you haven't already:

1. Install Visual Studio Code
2. Install the PlatformIO IDE extension
3. Restart VS Code

4. Build and Upload

1. Open this project folder in VS Code
2. PlatformIO will automatically install dependencies
3. Connect your ESP32 board via USB
4. Click the "Upload" button (→) in the PlatformIO toolbar
   • Or use: pio run --target upload

5. Monitor Serial Output

Click the "Serial Monitor" button in PlatformIO to see debug output:

• WiFi connection status
• Weather data updates
• Any errors

Pin Configuration

The default pin configuration in platformio.ini:

TFT_MISO = 12
TFT_MOSI = 13
TFT_SCLK = 14
TFT_CS   = 15
TFT_DC   = 2
TFT_RST  = 4
TOUCH_CS = 33

If your board uses different pins, update the build_flags section in platformio.ini.

Touchscreen & Brightness Control

This project targets the ESP32-2432S028 series 2.8" ILI9341 display that exposes an XPT2046 touch controller on the HSPI bus. Besides TOUCH_CS, the following pins are defined in platformio.ini and can be adjusted for other hardware:

TOUCH_MOSI = 32
TOUCH_MISO = 39
TOUCH_CLK  = 25
TOUCH_IRQ  = 36

The touch panel is calibrated in src/main.cpp through the TOUCH_RAW_MIN_*, TOUCH_RAW_MAX_*, TOUCH_SWAP_XY, and TOUCH_INVERT_* constants. Modify those values if taps appear mirrored or offset on your device.

Every tap on the screen cycles the TFT backlight between 33 %, 60 %, and 100 %. The default level on boot is 60 %, and the percentages/PWM steps live in BRIGHTNESS_LEVELS/BRIGHTNESS_PERCENT. Adjust those arrays if you prefer different steps.

Customization

Update Interval

Change the refresh rate in include/config.h:

#define UPDATE_INTERVAL 900000  // milliseconds (15 minutes default)

Display Colors

Modify colors in src/main.cpp using hex values:

lv_obj_set_style_bg_color(scr, lv_color_hex(0x1E1E1E), 0);  // Background
lv_obj_set_style_bg_color(title_bar, lv_color_hex(0x2196F3), 0);  // Title bar

Temperature Units

To use Fahrenheit instead of Celsius, edit include/config.h:

#define WEATHER_CURRENT_API_URL "/data/2.5/weather?q=" WEATHER_CITY "," WEATHER_COUNTRY_CODE "&units=imperial&appid=" WEATHER_API_KEY
#define WEATHER_FORECAST_API_URL "/data/2.5/forecast?q=" WEATHER_CITY "," WEATHER_COUNTRY_CODE "&units=imperial&appid=" WEATHER_API_KEY

Then update the display format in src/main.cpp:

sprintf(temp_str, "%.1f°F", weather.temperature);

Troubleshooting

Display shows nothing

• Check pin connections match your board
• Verify TFT_eSPI pin definitions in platformio.ini
• Try adjusting TFT_MISO, TFT_MOSI, TFT_SCLK, TFT_CS, TFT_DC, TFT_RST values

WiFi connection fails

• Verify SSID and password in config.h
• Check WiFi signal strength
• Ensure 2.4GHz WiFi (ESP32 doesn't support 5GHz)

Weather data not updating

• Verify API key is correct
• Check city name and country code
• Free tier has 60 calls/min limit
• Monitor serial output for error messages

"API Error" message

• Wait a few minutes (new API keys can take time to activate)
• Verify internet connection
• Check API key hasn't expired

Project Structure

esp32-weather-station/
├── include/
│   └── config.h          # WiFi and API configuration
├── src/
│   ├── lv_conf.h         # LVGL configuration
│   └── main.cpp          # Main application code
├── platformio.ini        # PlatformIO configuration
└── README.md            # This file

Dependencies

Automatically installed by PlatformIO:

• LVGL 8.3.11 (Graphics library)
• TFT_eSPI 2.5.43 (Display driver)
• ArduinoJson 6.21.3 (JSON parsing)

License

Free to use and modify for personal and commercial projects.

Credits

• Weather data: OpenWeatherMap
• Graphics library: LVGL
• Display driver: TFT_eSPI