Hi Josh,
Here is the reason your VI isn't working:
In order for your sub-VI (infrared checker) to stop executing, the digital line must return a value of "T". A "T" value is what stops your loop in your subVI. Therefore, in your outer loop, you have to have both of your subroutines return "T" in order for the loop to iterate. (the loop can't iterate until all of the subroutines inside of it have finished executing.) That is why the animal has to trip both lines before your outer loop will stop...both of your subVIs need to finish executing, and they can't finish executing until the digital line has returned a "T" value. Does that make sense?
In the picture I showed, both lines are read at the same time, so only one of them has to return "T" in order for the loop to iterate.
You either need to read both lines at the same time, as I showed, or you need to remove the loop from your subVI. When you remove the loop from your subVI, you'll essentially be duplicating what I showed you -- you'll just be using two tasks to accomplish what I accomplished with a single task.
To read both signals with a single task, you need to tell the task to read both lines simultaneously. I did this by specifying two digital channels: lines 0 and 1. (look at the syntax for the physical channel in my picture) Then use the same DAQmx Read instance that I used: multiple channels, single sample.
If you want to do this using a task in MAX, simply specify lines 0 and 1 (or whichever lines you're using to read your signals) as the physical channels for that task. Use <ctrl> to select multiple lines, the same way you'd use it to select multiple files in any Windows application.
Hope that makes things clear...
Diane
