I am doing rather simple alarm system with two loops and 5 PIR sensors to my garage with simple pushbuttons to turn alarm on or off. I have everything sorted and coded out but I started to think that will using millis() for calculating time in such project which will be on continuously for long periods, cause any problems? Especially one function what I want which will turn alarm on if no sensor has been active or doors open for 6 hours.
I have read that millis will jump back to zero for every 50 days or so. Will this cause any problems for my project to take consider? Any other solutions?