I need to find the frequency of a wave that does not oscillate between 0 and Vcc.....(hence no use of programmed interrupt for level detection) how do i find the frequency of the wave in this case?
if your freq is not oscillating between 0 and VCC, the best way is to convert the wave to this level and better use interrupts and timers, for fixed time window.
to convert it to reqd. level you can use schmit trigger ckts.