OK, but here comes the disclaimer. This is work in progress, the code is nowhere close to done. It requires an open collector DCF77 module @ pin 19 and is assumes that all pins have leds connected to them ("Blinkenlight Shield").
The code is in a transitional state. So it is NOT a DCF77 decoder yet. It is also not yet documented. But you asked for it 
Please do not distribute or ask for in depth comments. I will document it in my Blinkenlightblog once it is finished. The code works as expected without the debug calls. Once the debug calls are in it slowly gets out of sync. If I remove the print statements it stays in sync.
Blinkenlight_C0X_DCF77_decode_with_ms_samples.tar.gz (8.43 KB)