Parts Used

• MAX7219 8-digit display
• ESP8266 NodeMCU
• Wooden picture frame
• Wood-effect vinyl adhesive paper
• USB power supply

Build Notes

The display sits behind the frame glass or plastic, with the vinyl used to hide the electronics and soften the look. If you are happy to wait for parts, the build can come in at about EUR10.

I used D5, D6, and D7 for the display so it could connect directly to the NodeMCU and stay easy to troubleshoot.

Setup

1. Wire the MAX7219 display to D5, D6, and D7.
2. Fit the display behind the frame front.
3. Cover the visible backing with vinyl.
4. Upload the sketch and set your Wi-Fi details.

Code Notes

The code removed Wi-Fi Manager and uses a hard-coded SSID and password. The display updates every 12 hours and takes pricing data from Coindesk.

// Wifi Login
const char* ssid = "your_ssid";
const char* password = "your_password";