I'm in the process of designing/building an anemometer.  To measure
the speed of the wind, I'm going to be counting the number of
revolutions the shaft makes.

My question is: can I just a timing loop approach to counting the
number of revoultions or should I use a timing interrupt from a
real-time clock?

In other words, would this appoarch give me acceptable results:
        For i = 1 to NumberOfLoops
                if revolution detected then
                        NoOfRevs = NoOfRevs + 1
                endif
        next i

where I have computed the amount of time it takes to do the loop.  Or
would I be better off if I do something like:

        wait for timing interrupt
        while no timing interrupt detected
                if revolution detected then
                        NoOfRevs = NoOfRevs + 1
        wend

Thanks in advance for you comments/suggestions/ideas,


Richard Rosenheim
rrose@accessnv.com