Is it possible to read multiple different inputs on one Arduino board. I would like to read in as many as possible, I have seen that there seems to be one pin dedicated to reading in the frequency. So is there any arduino board that can read in multiple inputs and tell me the frequency of them. Also if there is any that have more than one pin that can do this what is the max voltage that this pin can handle. Since it is frequency i am assuming it will be able to handle AC. What would be the max voltage whether it be RMS or ac. Thank you.
The voltage limits means the pin cannot go above 5v or negative. The AC voltage peak is the that of interest, nor RMS.
You can use AC if there is an offset voltage to keep the voltage from going negative.