SAINTCON 2016 ESP8266 LED Badge
D1 Mini ESP8266 badge kit with MAX7219 LED display and Hackers Challenge registration
The SAINTCON 2016 badge was an electronic kit badge built around a D1 Mini ESP8266 development board, MAX7219 LED driver, and two 4-digit LED modules, with public assembly, flashing, and Hackers Challenge registration documentation.