Is someone can tell me if there's a difference between these two way of mesuring a pulse width.

First simply by using PULSIN

PULSIN PIN_IN,0,PULSE_WIDTH

Or by using WHILE WEND like this

WHILE PIN_IN = 0
PULSE_WIDTH = PULSE_WIDTH + 1
WEND

I know PULSIN increment by 10us step using a 4MHz Xtall. Do the While wend way can be more accurate ? Is there a way to know how many cycles required by this code ?

Thank you