Dot matrix clock with weather and NTP

This is my dot matrix clock made with ESP8266 WiFi capable MCU. Accurate time signal is acquired from NTP and weather information is available through Openweathermap.org API.

Features

• 24 hour time display
• NTP sync
• Optional weather data from Openweathermap.org API
• Outside temperature display
• Wind speed display
• Wind direction display
• DST support (automatic change)
• Over the Air (OTA) firmware upgrade capability
• WifiManager Soft AP configuration interface

Prerequisites

• ESP8266 board (recommended: NodeMCU/compatible see BOM)
• MAX7219 based LED matrix display (order from China)
• Openweathermap account (optional)
• PlatformIO

Time display screen

Weather display screen

Current weather is displayed 3 times per minute for 4 seconds.

Build & Installation HOWTO

Hardware BOM

• NodeMCU v3 board
• MAX7219 based LED matrix
• Micro usb to USB cable
• Female-female dupont cable 5pcs (usually comes with the display)

Wiring between NodeMCU and matrix board

NodeMCU 3.3V -> Matrix Vcc
NodeMCU GND  -> Matrix GND
NodeMCU D8   -> Matrix DIN
NodeMCU D7   -> Matrix CS
NodeMCU D6   -> Matrix CLK

Software installation

• Download and install PlatformIO
• Optionally read https://docs.platformio.org/en/latest/quickstart.html

PlatformIO automatically downloads all required libraries, boards, and configures your environment.

Optional steps for weather info functionality

• Openweathermap: http://openweathermap.org/

  • Register an account
  • Get your API key at: https://home.openweathermap.org/api_keys
  • Find your location/city id on here: https://openweathermap.org/find?q=

• Changes in file main.cpp needed for weather functionality

  • Add your api key from openweathermap: uncomment define WEATHERKEY
  • Add your city id from same
  • Save file

Uploading Firmware to ESP8266 module

PlatformIO serial

platformio run --target upload

PlatformIO OTA

platformio run -t upload --upload-port <IP address of ESP>

Wifi Configuration

• Latest version of the Firmware uses the WifiManager library by tzapu to setup the clock

• If no known WiFi AP is nearby, the clock starts the config portal

• Connect to SSID: "MatrixAP"

• Point your browser to 192.168.4.1

• Follow instructions to configure your SSID, pass, API key and CityID

• To manually force config AP mode, short D5 pin on NodeMCU to ground to enter

Obsolete config instructions for the serial version:

• If the clock fails to connect to an AP it will ask for credentials
• Run serial monitor (Arduino IDE) or minicom/putty, etc at 9600 bps
• Type in your own Wifi credentials

Future plans

• Dimmable display brightness (request)
• Multiple NTP time-zone support
• bugfix, testing

Special thanks

• Vajk for beta testing & original HOWTO
• William Moeur for NTP code