The first question to ask is are you getting any data in from the Oscilloscope? [This is the old "Is it the Hardware or the Software" question]. If you are getting a reasonable-looking Waveform in from the Hardware, then the problem is your Software, otherwise it is the Hardware.
Hardware first: If the WaveGraph wire is empty (or when you connect it to a Graph to see its contents, it looks "wrong"), try to use MAX's Test Panels to send GPIB commands to the Scope and read the Waveforms into MAX. Maybe it's simply "a Failure to Communicate".
On the other hand, if you have a good Waveform, then it's probably the Software. Simplify, Simplify, Simplify. Write a tiny Test VI using a "synthesized Waveform" (such as random numbers, or a Sinusoid from a Wave Generation routine) and test one or two of the steps you have in your larger program. Find where it "breaks" -- it is simpler to fix code with basically a single straight Wire path and 3-5 functions than one with multiple wires and functions.
Bob Schor
