I want to measure a very low frequency signal(5 Hz) by microcontroller(89c52).In order to have acceptable accuracy I have to take sample (of that signal)of many minutes,which is impractical.
I think there are two solution of the above problem:
(1)Multiply the signal frequency by using PLL.But what about the accuracy of measurment?
(2)Measure the time period of signal(interval measurement,intead of event counting) and calculate the frequency by taking reciprocal of it.
Which solution is more suitable,or there is any alternative?
Specialy for dear ERIK MAL.
Generally for all.