Color sensing (as well as detecting empty spaces) settled on IR-based sensors commonly used in line-following robots. You can watch the clock in action in the video embedded below just under the ...

V3.0 - Using NodeMCU ESP8266 for controlling switches (Relay). Uses RTC (Real Time Clock - DS3231) and NTP (Network Time Protocol) for maintaining time. OLED Display (128x64) for instant updates. A ...