ESPTimeCast is a WiFi-connected LED matrix clock and weather station based on ESP8266 and MAX7219.
It displays the current time, day of the week, and local weather (temp/humidity/weather description) fetched from OpenWeatherMap.
Setup and configuration are fully managed via a built-in web interface.

Get the 3D printable case!

• LED Matrix Display (8x32) powered by MAX7219, with custom font support
• Simple Web Interface for all configuration (WiFi, weather, time zone, display durations, and more)
• Automatic NTP Sync with robust status feedback and retries
• Day of Week Display with custom font
• Weather Fetching from OpenWeatherMap (every 5 minutes, temp/humidity/description)
• Fallback AP Mode for easy first-time setup or configuration
• Timezone Selection from IANA names (DST integrated on backend)
• Day of the week display in multiple languages
• Persistent Config stored in LittleFS, with backup/restore system
• Status Animations for WiFi conection, AP mode, time syncing.
• VEML7700 Ambient Light Sensor for automatic brightness control and display on/off based on ambient light
• Advanced Settings panel with:
  • Custom Primary/Secondary NTP server input
  • Display Day of the Week toggle (defualt in on)
  • 24/12h clock mode toggle (24-hour default)
  • Imperial Units (°F) toggle (metric °C defaults)
  • Show Humidity toggle (display Humidity besides Temperature)
  • Weather description toggle (display Rainy, Clouds, Thunderstorm etc.)
  • Show LUX Reading toggle (display ambient light level)
  • Flip display (180 degrees)
  • Adjustable display brightness
  • Dimming Hours Scheduling
  • LUX Threshold for turning off display in dark environments

Note: although the pins are labeled differently in the V4, the positions are the same as the V3.x

Wemos D1 Mini (ESP8266) → MAX7219

Wemos D1 Mini (ESP8266) → VEML7700

Note: Thanks to @Wood578Guy for the Wiring diagram and the info on V4

The built-in web interface provides full configuration for:

• WiFi settings (SSID & Password)
• Weather settings (OpenWeatherMap API key, City, Country, Coordinates)
• Time zone (will auto-populate if TZ is found)
• Day of the week languages
• Display durations for clock and weather (milliseconds)
• Advanced Settings (see below)

1. Power on the device. If WiFi fails, it auto-starts in AP mode:
   • SSID: ESPTimeCast
   • Password: 12345678
   • Open http://192.168.4.1 or http://setup.esp in your browser.
2. Set your WiFi and all other options.
3. Click Save Setting – the device saves config, reboots, and connects.
4. The device shows its local IP adress after boot so you can login again for setting changes

Click the cog icon next to "Advanced Settings" in the web UI to reveal extra configuration options.

Available advanced settings:

• Primary NTP Server: Override the default NTP server (e.g. pool.ntp.org)
• Secondary NTP Server: Fallback NTP server (e.g. time.nist.gov)
• Day of the Week: Display Day of the Week in the disered language
• 24/12h Clock: Switch between 24-hour and 12-hour time formats (24-hour default)
• Imperial Units (°F) toggle (metric °C defaults)
• Humidity: Display Humidity besides Temperature
• Weather description toggle (display Rainy, Clouds, Thunderstorm etc. for 3 seconds)
• VEML7700 Light Sensor: Enable/disable the ambient light sensor
• Show LUX Reading: Display the current ambient light level
• LUX Threshold: Set the light level below which the display turns off
• Flip Display: Invert the display vertically/horizontally
• Brightness: 0 (dim) to 15 (bright)
• Dimming Feature: Start time, end time and desired brightness selection

Tip: Dont't forget to press the save button to keep your settings

• OpenWeatherMap API Key: Get yours here
• City Name: e.g. Tokyo, London, etc.
• Country Code: 2-letter code (e.g., JP, GB)
• ZIP Code: Enter your ZIP code in the city field and US in the country field (US only)
• Latitude and Longitude You can enter coordinates in the city field (lat.) and country field (long.)
• Time Zone: Select from IANA zones (e.g., America/New_York, handles DST automatically)

1. Clone this repo
2. Flash the ESP8266 using Arduino IDE or PlatformIO (Flash size "4MB FS:2MB OTA:~1019KB")
3. Upload /data folder with LittleFS uploader (see below)

• Install ESP8266 board package:
  http://arduino.esp8266.com/stable/package_esp8266com_index.json
• Select Wemos D1 Mini (or your ESP8266 variant) in Tools → Board
• Select Flash Size "4MB FS:2MB OTA:~1019KB" under Tools

Install these libraries (Library Manager / PlatformIO):

• ArduinoJson by Benoit Blanchon
• MD_Parola / MD_MAX72xx all dependencies by majicDesigns
• ESPAsyncTCP by ESP32Async
• ESPAsyncWebServer by ESP32Async
• Adafruit VEML7700 Library by Adafruit

Install the LittleFS Uploader.

To upload /data:

1. Open Command Palette:
   • Windows: Ctrl+Shift+P
   • macOS: Cmd+Shift+P
2. Run: Upload LittleFS to ESP8266

Important: Serial Monitor must be closed before uploading!

ESPTimeCast automatically switches between display modes: Clock, Weather, Weather Description (if enabled), and LUX Reading (if enabled). If "Show Weather Description" is eneabled a third mode (Description) will display with a duration of 3 seconds, if the description is too long to fit on the display the description will scroll from right to left once.

What you see on the LED matrix depends on whether the device has successfully fetched the current time (via NTP) and weather (via OpenWeatherMap).
The following table summarizes what will appear on the display in each scenario:

• The display automatically alternates between Clock, Weather, Description (if enabled), and LUX (if enabled) modes.
• In Clock mode, if NTP time is available, you'll see the current time plus a unique day-of-week icon. If NTP is not available, you'll see ! NTP.
• In Weather mode, if weather is available, you'll see the temperature (like 23ºC). If weather is not available but time is, it falls back to showing the clock. If neither is available, you'll see ! TEMP.
• In LUX mode, you'll see the current ambient light level measured by the VEML7700 sensor.
• All status/error messages (! NTP, ! TEMP) are big icons shown on the dsiplay.

Legend:

• 🗓️ Day Icon: Custom symbol for day of week (@, =, etc.)
• ⏰ Time: Current time (HH:MM)
• 🌡️ Temperature: Weather from OpenWeatherMap
• 🔆 LUX: Light level from VEML7700 sensor
• ✅ Yes: Data available
• ❌ No: Data not available
• — : Value does not affect this mode

If you like this project, you can buy me a coffee!