my question:
what is the best way to measure a digital input with an interval of 25 seconds.
when it is measured as LOW at the beginning , I would like to measure again after 25 seconds whether it is still LOW and then take appropriate action. In the mean time nothing should actually happen.
What to use??
interrupt routine, use of millis() or delay function, or even other??
project: measure AC power and is it down for more than 25 seconds , start the generator via relay and remote terminal, when mains power is back , stop the generator. I have a mechanical ATS (see picture) which automatic switches the load from mains to generator.
ats2 shows how electronic ats works..
thanks in advance
Leo Smit