Hi there,

@Henrik

I was thinking of using a 12F615. The MCu will only have a tight loop where it's just waiting for the inputs to start.
After stopping it will analise the results and can go back to wait for signals again or move forward.

@Alain

Yes... both start and stop together...the problem is that the pulses ( 35ms ) may vary in quantity in the same period of time.

Regards
Rui