measure the xtal

[savnik]

To measure something, anything, you have to have an accurate timebase. To measure the internal clock of the PIC, using that same internal clock as your timebase as you've shown in your brief example, doesn't work.
Do you have an o'scope?

Yes i have.
Or how to measure a xtal on RA4;
I want to measure the frequency of a oscillator with xtal or from a signal connecting to RA4