1 count = 1.47mph with 100ms sampling time

Hence make your sampling time 68ms.
If you get 2 counts in 68ms the windspeed is 2mph.

 

arg, I can't stand it any more...

Measure the time between two pulses. The rest is left as an exercise to the student.

 

arg, I can't stand it any more...

Measure the time between two pulses. The rest is left as an exercise to the student.

That's what I'm trying to do, I was counting the rising of the pulses but measuring the time between two pulses will be more accurate, thanks for your answers! They were helpful.