But the arduino start the code by adjusting the time to 2pm again. So once u set already, comment that line out and upload again. Eagle file for schematic & layout (DS1307 RTC Module V1.0) Hope you ...

But the board also breaks out pretty much any I/O you could possibly want from the CM4, and even includes some of its own niceties like an RTC module and ... say goodbye to SD cards.