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how to sync analog input with signal genereration and DIO

hardware :
 
analog output card : PXI 6711
analog input card : PXI 6143
 
i am trying to apply a set of analog and digital values to my hardware which prich produces an analog result,which i acquire via my analog input card. the problem i am having ( i think) is syncronising the analog input to read after the digital and analog data is outputted and my hardware has settled.
 
please see attatched VI .
 
the VI does work but not as fast as i would like it, it currently gives around 140 sets of measurement  per second. however i have in past got it to work art around 350 sets of measurements per second which would be acceptable.
 
i know my hardware has a settling time of around 400 micro seconds therefore i would require the analog input to start reading 400us after the control signals are outputted.
i have tried various methods (sequence structures, wait states etc) to execute the analog input 1ms (smallest wait available in labview) after the controll signals but this gives me eroneous data.
currently i am controlling the delay for the analog input by the iteration number on the for loop,  i sart to get incorrect data when set to a value less than 50.
 
can someone please help me out!
 
thank you in advance 
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Message 1 of 3
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Hi,
  I think I follow what you're doing.
If you set up the analog output as hardware timed single point, and run it at the rate of the analog input / number of samples per read, and run the read as finite, then you can set a trigger on the analog input task whenever the sample clock for the analog output updates, and there's a property node that then allows you to set a delay from the trigger to the start of the acquisition.
 
Hopefully the vi will explain that more clearly.
 
Hope that helps

Thanks
Sacha Emery
National Instruments (UK)
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Message 2 of 3
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thanks for your suggestion but your method doesnt seem to work!
 
i have found another solution to my problem which similar to my original!
once again thanks any way
 
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