How can I measure the frequencies of two analog input signals simultaneously?

Hi
I have two AI signals, and I need to determine the frequencies of those signals. The frequencies range from 1-125Hz. I currently have a VI where I can sample one of the signals for 1 second (sampling at 300 Hz for 300 samples) and determine the frequency.
I need to read two signals at the same time and get both of the frequencies at the same time, but I can only figure out how to read them individually, so I can read one signal, then one second later I read the second one, then I read the first one again, then the sceond one, etc.. How can I read two signals simultaneously?
Thanks
Attachments:
FreqMeas11.vi ‏41 KB
FreqMeas11.PNG ‏18 KB

"at same time", this depends on the hardware, you can do as has been previously stated just set up a 2 channel acquisition and you will get 2 sampled waveforms back. Most hardware A/D as multiplexed and true simultaneous sampling is not done. At 125Hz this is not an issue unless you are interested in very small phase changes between the samples. just keep this in mind if you are expecting samples to be completly synchronized.
Paul
Paul Falkenstein
Coleman Technologies Inc.
CLA, CPI, AIA-Vision
Labview 4.0- 2013, RT, Vision, FPGA

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I'm trying to measure the time in seconds between each two successive rising edges on a digital input .
Till now I have managed to detect the rising edge ,increment a counter with each rising edge ,and snap the time at which the rising edge happenned
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Go to Solution.
Attachments:
Counter without time.vi ‏11 KB

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How can I measure the time between each two successive rising edges ,using Digital Input ?

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Till now I have managed to detect the rising edge ,increment a counter with each rising edge ,and snap the time at which the rising edge happenned
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Solved!
Go to Solution.
Attachments:
Counter without time.vi ‏11 KB

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Spoiler (Highlight to read)
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Time between clicks.vi ‏9 KB

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