The DCF77 receiver is connected to digital pin 15. The sketch attaches an interrupt to measure the length of the pulses. A 0.1 sec pulse is binary 0, a 0.2 sec pulse is binary 1. One pulse per second, ...
This Arduino library, is a display like driver based on the Adafruit_GFX library to drive the Charlieplex display on the Arduino UNO R4 WiFi boards. This is an alternative to the library ...