I'd figure a small adaptation to the examples that come with the various DS3231 libraries should do the job.
Hi Yahenda,Here's a thought. Why not simply plug the system into a timer? You could modify the sketch to only run for a short amount of time then stop. The next day the timer will restart the system... every day.Plus the system won't need to be powered all of the time.Pat.
wvmarle,Yes, exactly like that. Just a simple timer that automatically turns a lamp on / off in the evening.
It's trivial to hardcode these things, but changing them tends to require a fair amount of code because anything that is going to be adjusted by an actual person requires a lot of error-handling work. That's where most of the work (and cost) comes in.
I would rather put a start button and let the cat push it whenever it likes.
I have solution for that via external webserver for Arduino with Ethernet shield. If some interested, PM.
Maybe it's just me, but this seems like so much overkill for a basic timer.