[Wolf] sent in this site a while back, and I thought that this frequency meter how-to looked pretty useful. It’s based on an Atmel AT89C52 and a gutted multi-meter. The circuit isn’t too bad. (The ...

This frequency meter project squeezes a lot of performance out of the ATtiny2313 microcontroller. That chip does all of the work, measuring the frequency on the input pin as well as multiplexing the ...