DAQmx triggering

[lmhensto]

Im relativley new to labview and I have a problem trying to setup Triggering using DAQmx

Im am using NI 6210 to aquire data from AI sensor - what Im am wanting to do is aquire data each time the proxistor is triggered from my Digital Input.

So what I require is to capture 1 cycle of data and save the data on each cycle to be used at a later date to pick off certain samples at a specified time.

I have setup a test (VI attached) which at the moment is using the Boolean Crossing to see when the proxistor goes high and when this accurs the task is started and data captured and the task is stopped when the proxistor goes low. This seems to be working ok from what i have been told is that this is not a very good way of timing and I can see that samples captured are not the same each cycle so for the aquistion I would need to look at another way in which to capture 1 complete cycle of dat using the DAQmx triggering. I have been thorugh the NI examples but from these cant find a way in which to implement the triggering for what I need. I also have read that this series of card does not allow re-triggering which is somthing that i would need to implement?

Any help/advise would be greatly appreciated.

[lmhensto]

To explain further - please see attached JPG.

[david.bolt]

Dear Imhensto

I have been working on your problem and I have a solution for you. First, to clarify, the NI 6210 does not have retriggering capabilities and hence this problem you are trying to solve is a little more complex as you are trying to accomplish alot with a basic device. 

I have attached the VI  below for your viewing and hopefully this will offer you some help on what you want to accomplish. Aviod using boolean crossings and use the daqmx tools palette when acquiring synchornous data. If you want to acquire the data to be used for analysis, connect an array to the VI to get this data. Select your appropiate input channels for your devices and run the program. You will see that when the digital edge is triggered it returns back to zero and at this edge it will correspond to an analog value.

I hope this is of some help.

[lmhensto]

Hi David,

Thanks for the reply - unfortuatly I cannot open the the VI as I am currently using LabVIEW version 8.6.1 -

Would it be possible to attach the VI with this version?

Thanks

Lee.

[david.bolt]

Hi Imhensto.

Thanks for the quick reply. Please try the VI below. Hope this helps.

[david.bolt]

Dear Imhensto

How did you get on with the VI I attached? Let me know if I can help with anything else. Many thanks!

[lmhensto · Accepted solution]

Hi David,

sorry for the late reply -

Yes the VI that you provided has helped me out a lot and is a good start for me in helping me to get to what I need to achieve.

Thanks for your help

lee.

[david.bolt]

Glad I could help Imhensto. Sorry to be pernickity but can you please mark the correct solution. Many thanks!