Currently I am trying to measure the time consumption of an interrupt routine. How I (want to) do it:
1. Setting up a measurement unit using the timer/counter block TC0 CH1. With this TC the time of any kind of routine shall be measured by starting and than stopping its clock and then reading the value of its register (.cv => counter value);
2. Setting up an ISR of which the execution time shall be measured. The ISR shall be triggered by an external signal (I am using ExtInt1 for this purpose).
Well, having this set up it didn't work out as I thought.
Now, my question is: While processing the ISR, this will not affect any timer (in my case TC0 CH1)?!
My understanding is, that the timer/counter is running independently of the processor, so if an ISR is being processed it doesn't affect it. But what I currently see is, that the TC0 CH1 seems stop counting up while the ISR is being processed. It still can be a bug in my application. But after 3 hours seraching I still couldn't find any wrong implementation. Therefore I posted this question.