How to measure Pulse signals

Hello, Friends
I am interested in developing a data acquisition program from a sensor that gives a pulse signal. I would like that send me please some information about what VI’s I have to use inorder to began the acquisition and How I can measure the pulse frecuency. Some examples will be very excellent.
Please, write me. I will be very thankful
Pablo

You should be able to findout the output of the signal, is it an analog voltage or is this pulse a digital pulse (ie measuring TTL Width or some number of counts for a frequency changing pulse train)? All this is either done with DAQMX analog in vis or counter vis. You really need a clear picture of what the signal is before you can write code. The code should be simple once you know your signal.
Paul
Paul Falkenstein
Coleman Technologies Inc.
CLA, CPI, AIA-Vision
Labview 4.0- 2013, RT, Vision, FPGA

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This account is no longer active. Contact ShadesOfGray for current posts and information.

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:-) I heard that problem before. Is it possible that we disscused this subject some time earlier?
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Attachments:
drawing of torque signal.gif ‏26 KB

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Attachments:
peak_find_screenshot.jpg ‏45 KB

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Acq&Graph Voltage-Int Clkv1.vi ‏190 KB

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Attachments:
Results_Waveforms.doc ‏141 KB

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You might want to search the Knowledge Base on the NI's Support Pages for "Cable Mapping for a 68 Pin Connector to a 50 Pin Connector". This should take you to a link that will explain the mapping of a 50way to 68way cable and subsequent lines you are looking for ( reference sub link 68F50M), I guess you have SH6850 cable connected from the AT-MIO16 card to the SCB-68.
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I have attached a jpg (a graph that i just made with excel to explain). The time 't' is what I am trying to measure
Cheers
Awais
Message Edited by awais.h on 03-30-2010 11:20 PM
Message Edited by awais.h on 03-30-2010 11:21 PM
Solved!
Go to Solution.

Hi
Thanks for the code but I'm afraid it won't work. Like you said the probability of choosing a value that is on both graphs may not happen. This is something that I would like the code to do automatically.
But I did use the previous code posted and made some modifications to it and it seems to work perfectly. Now the next thing is to be able to get just that one value that tells you the first time difference.
Here is what I get using that code.
As you can see from the t Values. I only need the one that is highlighted. If there is a way to filter out the rest it would be great.
I was thinking of a while loop and as soon as the value is higher than 3E-5 it would store the number and stop the loop, but I'm not too familiar with arrays in labview.
Here is the the code modified.
As you can see, it wasn't that big of a modification and it still is your code.
I will keep trying.
Thanks for the help
Attachments:
FinalShockSpeed.vi ‏55 KB

How can I use counters to read the difference between two external pulse signals?

I generated a pulse signal and sent it to a sensor which in turn gives me a pulse signal back. I need to read the time from which the sent the signal goes high to the time that the signal is returned. How can I read this? the diagram is attached
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Timing_Diagram1.doc ‏256 KB

There is vi called "Two Edge Separation Mesurement (NI-TIO).vi". In LV6.1 it is in "c:\...\LabVIEW 6.1\Examples\DAQ\Counter\ni-tio.llb".
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This function will only work with NI-TIO cards (like 660x).
Attachments:
Two_Edge_Separation_Measurement_with_Timeout_(NI-TIO).vi ‏103 KB

How can I use counters to read the difference between two expernal pulse signals?

I generated a pulse signal and sent it to a sensor which in turn gives me a pulse signal back. I need to read the time from which the sent the signal goes high to the time that the signal is returned. How can I read this? the diagram is attached
Attachments:
Timing_Diagram1.doc ‏256 KB

Hello;
The way to accomplish that is by using one of the 660x boards, and configure the counter to do "Edge Separation Method".
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How to measure a current signal with NI 6211?

How to measure a current signal with NI 6211?

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How to measure Pulse signals

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