How to acquire and read data before trigger?
Hi, all:
I want to acquire a impluse signal, and the data when the signal begins is very important to me. So, I want to using a digStart trigger to acquire it, but then i'll lose what i want, maybe i can acquire it continuously, and use the trigger to start read the buffer after a delay(in order to wait the signal end), i don't know if there is any ANSI C functions I can use to do it in this way. I am using PCI6220, DAQmx9.02 and ANSI C. If anyone have some info on this please let me know. thinks.
Hi Cris Brown:
From your application,I suggest that you can use DAQmxCfgDigEdgeRefTrig function; define pretrigger samples fitting for your application.
Try it. Best Regard!
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I've attached a VI that I am using to acquire amplitude from Spectrum analyzerse. I tried to connect amplitude ouput to the VI Write Characters To File.vi and Write to Spreadsheet File.vi. Unfortunately when I run continual this VI without interruption, labview ask me many time to enter a new file name to save a new value.
So, How can I do to aquire and save date in the same time and in the same file when I run continual my VI for example during 10 min.
Thank you in advance.
Regards,
Attachments:
HP8563E_Query_Amplitude.vi 37 KBHi,
Your VI does work perfectly. Unfortunately this not what I want to do. I've made error in my last comment. I am so sorry for this.
So I explain to you again what I want to do exactly. I want to acquire amplitude along road by my vehicle. I want to use wheel signal coming from vehicle to measure distance along road. Then I acquire 1 amplitude each 60 inches from spectrum analyzer.
I acquire from PC parallel port a coded wheel signal coming from vehicle (each period of the signal corresponds to 12 Inches). Figure attached shows the numeric signal coming from vehicle, and the corresponding values “120” and “88” that I can read from In Port vi.
So I want to acquire 1 time amplitude from spectrum analyser each 5
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Here is a new algorithm.
1) i=0 (counter: number of period)
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file this amplitude and the corresponding distance
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Corresponds to 12 Inches).i has to take these
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Thank you very much for helping me.
Regards,
Attachments:
Acquire_Amplitude_00.vi 59 KB
Figure_Algorithm.doc 26 KB -
How to loop and read repeating table data of infoPath form in Visual studio workflow.
Hi,
I am trying to read info Path form repeating table data in Visual studio workflow.
could anyone elaborate me in brief how to loop through repeating table and read all rows value one by one in workflow.
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Thanks...Hi Rohan,
According to your description, my understanding is that you want to create a Visual Studio workflow to get data from info path repeating table.
I suggest you can submit Repeating Table to a SharePoint List and then you can create a .NET workflow to read data from the SharePoint List.
Here are some detailed articles for your reference:
Codeless submitting InfoPath repeating table to a SharePoint list
Create a Workflow using Visual Studio 2010
Best Regards
Zhengyu Guo
TechNet Community Support
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