To display the number of times that the valve has been opened and closed -- use the Statistics -->Counter module and count edges (Rising or Falling).
You can use this count to count down from a larger value by subtracting using an Arithmetic Module.
I considered using Global Variables, but, they may not update precisely enough... you need to keep the count and the countdown as data channels. Use a Trigger module to respond when the difference drops below 1.
Note -- you're more likely to get a response to DASYLab specific questions in the DASYLab forums. Go to www.dasylab.com and click on the Forums to see the page with the forum links.
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www.mccdaq.com and click on the "Support" tab for all support options, including DASYLab.