How to measure the slope of a triangle wave

Hi everyone,
I'm looking for a way to measure the slope of a triangle wave, which changes every half cycle of the wave. I have the triangle wave out of phase by 90 degrees so that it models the behavior of a cosine wave, and essentially all I want is a way to measure whether the slope is positive or negative. The idea is to use this information to stop another signal running at the same time at the halfway point of the cycle of the first signal, so the first wave can continue back to it's starting point and the second will start again at the completion of the first wave (as it begins the second cycle)
I'm using LabVEIW 8.2.1 if it makes a difference
Thanks,
Ben
PS. Is there a way to close threads you've previously posted on this forum? I started one yesterday (or possibly the day before) with a fairly vague question in it and it's now redundant after I made some headway on my own, and I don't want to clog the forums up

I'm not sure how you're using this data to control anything, so I'm not sure what the best implementation would be. You will not be able to get any data out of the loop until it finishes (gets a True value at the Stop If True terminal (sort of)), so if you want to have the loop running constantly, you need to put your control code in the loop with the generated data. Otherwise, you could generate your boolean array, and then wire it and your control array into a for loop, and do a point by point comparison to see if you should be controlling.
The new example.vi has two examples to give you a rough idea what I'm talking about.
Message Edited by JeffOverton on 06-12-2008 12:19 PM
=============
XP SP2, LV 8.2
CLAD
Attachments:
Example2.vi ‏18 KB

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