How to find the frequency of a squarewave?

Hi!
I want to find the frequency of a squarewave applied to a analog channel on a DAQmx 6225 card. I have four squarewave signals and two are connected to the two counter inputs available. the other two are my problem. Is there a simple way to extract the frequencies from these two signals? I have tried using the Pulse Measurements VI but it is working unsatisfactory. The frequncies I want to measure is from 20 to 2000 Hz.
Can anyone help me in this matter?
I use LV 7.1 and DAQmx 7.4

Hello!
Just like Dennis mentioned in his reply:
You have created several tasks for various analog input operations and these occur at the same time but since a task reserves the analog input circuitry on the board that means that another task cannot reserve it until the first task are done executing. That is what causes the errors you are experiencing.
Just combine the various analog input operations into one single task instead and you are pretty much set. If you need different sampling rates on the analog input operations I refer to the following link:
http://digital.ni.com/public.nsf/allkb/96FD2F4685065C7686256F25006EE8DE
Regards,
Jimmie A.
Applications Engineer, National Instruments
Regards,
Jimmie Adolph
Systems Engineer Manager, National Instruments Northern Region
Bring Me The Horizon - Sempiternal

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