Your XY Chart only shows the most recent capture. If you want to have an array of them, you have to build an array.
Put a shift register on the WHILE loop. Initialize it with an EMPTY array of X-Y pairs. Inside the CASE TRUE, append the new X-Y pair (you just captured) to the shift register left side and put the new array out to the right side Inside the CASE FALSE, pass the shift reg thru unchanged. You can plot the new array inside the TRUE case, if you're not concerned about speed (it will plot every time you click the button), or outside the while loop (it will plot only after you stop). Outside the while loop, save your data to a file.
