glitches when using time overflow interrupt

I have some trouble with, I guess, the overflow interrupt (used to increase resolution on 8-bit timer from 16µs/step to 1µs/step) in my CODE. It seems like the overflow interrupt triggers while the program is in the if-statements in my main loop and thereby screws thigns up!

I use an ATtiny85 as a RC-switch, it should go LOW on PB2-pin when µs from receiver is above 1555 and go HIGH when µs goes below 1490.
What happens is the following: when checking if µs is above 1555 or below 1490 and using overflow interrupt it sometimes turn the PB2-pin HIGH/LOW in the “dead-span” of 1490-1555 when it shouldn’t, and sometimes outside the “dead-span”!

I’m quite new at this and I’m not sure why this is happening and I don’t understand why the code won’t work. I have looked at the CTC function but I can’t see that it would help since I still have to use the timer overflow interrupt to get my wanted reolution of 1µs/step.


Source: c#

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