"Then resolution defines whether to measure time of one period or counts per fixed time interval."

Exactly. Thats what I wanted to convey in the last line of my post. But couldnt word it the way
you did.

Thank you, Rgahunathan. I was also surprised how professional it sounded... {grin}

By thy way, did Hatem already told us the range of frequency of interest?

Have a nice day,
Kai