jball:
interrupts(); // starts interupt
delay(1000); //waits 1 sec
noInterrupts(); // ends interupt
Why start and stop interrupts at all. Let the interrupt continue all the time but just zero the count, wait a second and then read the count. You have the information you need now and it does not matter if the interrupt count continues or even overflows and wraps around because the next time you ready to take a reading the count is zeroed.