Hello,
It sounds like you have two types of tasks going on, Counter Input and Analog Input. Since you are using a trigger from a pedal to start the acquisition, I would think that you're not just doing counter input because you can't actually trigger to start a counter task (unless you are using the signal as the gate - let me know if this is the case).
You will want to set you're counter to continuous edge count and if you are in fact using analog input, I would use AI digital start trigger with reference trigger. The first trigger would tell the acquisition to start, and then the data would be acquired, but not transferred to the PC buffer until it receives the second trigger (reference trigger). This might not be exactly what you want since it sounds like you would want to be acquiring data the entire time between the two triggers. This example program will demonstrate how to program such that you have
Continuous AI with both Start and Reference Triggers.
One problem that you may run into is that you will have to do some software programming to stop the continuous counter input task. Or maybe I'm misunderstanding and you don't really want a hardware stop trigger at all. If this is the case then all you would need to do is wire some type of logic to the conditional stop terminal in the while loop that stops upon some user interaction.
In regards to obtaining particular values out of an array - use the Index Array.vi in the Array palette. The context help will shine some helpful information on that VI.
Best Regards,
Jared A