Capacitor tester

Question

Hi everybody, 
I'm new at labview and was hoping if someone could help with a basic question.
I have to make a program that checks capacitors, the program uses a Velleman card VM110N or K8055.
I try to give is short and simple:
-Measure time.
-send 5 volts (255) to the card (which has a resistor and a capacitor wired up to it)
-measure the time it takes to get over 63% (this is 1 Tau)
-charge another 5 tau until fully charged.
the program also has to discharge, measure time etc again, calculate tau again, discharge another 5 tau, rinse and repeat, with the data you can calculate the capacity of capacitor and give approval or disapproval by a led lighting up and finally save it into an excel document.
but for now I'd like it to just charge, measure time until 63%, then I'd have 1 Tau,  (and then charge 5XTau.)
The rest I should be able to manage.
even if you don't have that velleman card I hope you can give some comments what I did wrong, I set it up pretty basic, remember I'm just a beginner, only the stuff in the flat sequence is mine, the rest was set up already, I've been at this for ages (really, I'm too embarrassed to even say how long), I'm sure it's quite simple, but if someone could just give me a clue or two.
Hope someone can help me, thanks so much in advance!
(ps I posted this somewhere else too, but I thought this was a better location for my question even though this thread is very old)
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Answer 1

Mark1357,
It would be better to start a new thread since this one is marked solved. Many people do not pay much attention to old, solved threads. This is probably the best Board for your question.
1. Please look at the online tutorials for Getting Started with LabVIEW.
2. With a state machine architecture you would only need one loop and no local variables. Multiple loops are not a problem although the way you have used them limits the flexibility of your program. Local variables may lead to race conditions. The Con local might be written before or after the terminal is written inside the loop. In practice it will amost always be written first but this cannot be guaranteed by your code. Similarly the 1 Tau local in the seqeunce structure might be read before or after the terminal is written.  These race condtions can produce unexpected results.
3. The Tick count in the first frame of the sequence structure executes in parallel with the CLFN (Output). No way to know which happens first.
If the DLL takes less than a millisecond to execute, it does not matter. It would be better to put the Tick Count in a separate frame after the CLFN node.
4. The one iteration loops could be eliminated by wiring the error clusters in and out. Learn how data flow works to your advantage.
5. There is no need to write the Scope property nodes every millisecond. Learn to use the event structure so that you only write to the property nodes if the x-axis length changes.
6. If the device is not connected the middle while loop still runs once and the inner loops will still wait for the user to press the end program (Stop) button. Better: Enclose the middle loop in the True case of a case structure.
7. There is no need for the 1 ms Wait in the outer loop when the inner loop has a 20 ms wait.
Lynn