Detect frequency of a square wave: sbRIO and myRIO

[cacalderon]

Hello LabVIEWERs.

I need to measure the frequency of a square wave with variable frequency from 1 Hz to 100 kHz (This signal is the output of an electronic device). I chose RIO platforms with the aim of measuring the highest possible frequency.

I have four options:

- Option 1: Use the Analog Input of the myRIO card.

- Option 2: Use the Digital Input of the myRIO card.

- Option 3: Use the Analog Input of the sbRIO card.

- Option 2: Use the Digital Input of the sbRIO card.

I need help on:

Question 1: Which option will measure with greater accuracy?

Question 2: Which option will measure with greater range?

Question 3: What will be the functions that I must use in LabVIEW (RIO, FPGA, RT…) to measure the frequency? (based on the response to Question 1).

I attached a referential image of the question.

Thanks.

[crossrulz]

1. As long as your digital signal is in the 3.3V or 5V amplitude range, the digital would be easier

2. For your range, probably no real difference.

3.What you will want to do is use the FPGA to count the number of pulses you get in 1 second.  So you will need a counter for the number of pulses you have measured and another one for number of cycles you have measured in (counting up to your 1 second).  When the 1 second has elapsed, update your indicators and reset your counters.