There is no version of the LEDclock with RTC and an RTC version will never be developed by myself (the DCF77 version works way too well, even in the UK). Feel free to analyse the ASM sources (they are documented) and replace the DCF77 routines by your own I²C RTC routines. When I find the courage I will draw flow charts of the different routines and their interconnections which makes the understanding a lot easier.
Update Updates to the original ZIP file are in bold/underlined. Overview of the Rev.H Clock PCB, ready for production:
