Where is "SampTimingType" selected?

[dav2010]

Can someone tell me where  "sample timing type" is selected?  I am getting the error shown in the attached picture when I STOP the vi. The vi is intended to measure the time between ON digital signals input to a USB-6501.  The vi is not doing anything while it runs...very confused here.   I realize that there are many other problems with this vi, but, if you can help me understand this particular error message, maybe that would help me to fix the remaining problems.   Thanks for your comments.

Dave

[Dennis_Knutson]

You've already been told that the 6501 is software timed only. Putting in a Sample Clock function is not going to magically change the hardware.

[dav2010]

Dennis,

Please show a little bit of patience, as I am learing the functions of Labview.  I am not trying to do magic, just trying to LEARN how to use Labview, and it is very challenging because of the enormous amount of features included in Labview.

Should I simply remove the sample clock from the vi?  Can you explain to me the function of the sample clock as it relates to hardware timing vs. software timing?  The vi I posted was derived from another vi that used a voltage reading module for the cDAQ chassis.  How do I understand when to include the sample clock and when not to?  I do not understand the error that is shown in my post.  Can you please offer some detail to help me UNDERSTAND the error in this vi?  Assume that my knowledge of Labview is still very novice, which it is.

Thank you,

Dave

[Dennis_Knutson · Accepted solution]

The Sample Clock function sets the hardware based timing between multiple samples. You must remove it. The time between samples in the example is going to be subject to a great deal of jitter.

[dav2010]

 Thank you.

David