Hello,
I am trying to trigger an on demand pulse from an HP 33120A function generator.
The pulse has to be a single, 0-5V ramp with adjustable frequency/period. I was able to get as much from the FG by using Burst and manually triggering off the front panel. Now I would like to get the same functionality from a LabVIEW VI.
While there is a driver for the device, the burst function is, unfortunately, not applicable to the model I am using. I found a similar issue on the forums and followed the SCPI code provided in the answer with some of my own midification (http://forums.ni.com/t5/LabVIEW/33120A-Pulse-Mode/td-p/1088106).
Unfortunately, my VI is not producing the same waveform as the manual triggering off the front panel. It hovers at the offset value and gives me a few square waves down to zero when I run the VI. The square waves are oddly spaced and I usually see 4-5 even though I specified 1 cycle in the VI. Reading through the 33120A, I get the impression that the issue is my not turning off the previous waveform but, if that's the case, I can't figure out how I would do that.
I am starting to move away from only using drivers and into modifying SCPI code but I am still quite new to this. Would really appreciate some advice on what the problem could be. I modified my original VI twice; once to configure only the burst with the FG wave parameters set manually and once to just set up the waveform with no burst. The former did not give me much better results and the latter works fine so I'm back to thinking the issue is in the transition.
I am attaching the initial VI (b) with the two modifications just in case (c, d).
Hope to hear from you,
Yusif Nurizade
Edit: Burst string should say TRIG: SOUR BUS instead of EXT although neither works.