title: Acquiring waveform of LeCroy oscilloscope with PyVISA
body: <p>I am trying to acquire a waveform from a LeCroy Teledyne HDO4024A oscilloscope. I'm using the <a href="https://lecroydso.readthedocs.io/en/latest/index.html" rel="nofollow noreferrer">LeCroyDSO library</a> and I've been able to communicate with the oscilloscope. For example, I could change the vertical scale with:</p>
  <pre><code>from lecroydso  import ActiveDSO, LeCroyDSO
  connection_string = 'VXI11:168.252.89.210'
  dso = LeCroyDSO(ActiveDSO(connection_string))
  dso.write_vbs('app.Acquisition.C1.VerScale=1')
  </code></pre>
  <p>To retrieve a waveform, I've tried various approaches, all without any luck:</p>
  <pre><code>data = dso.get_waveform('C1')       
  data = np.array(dso.query_vbs('CURV?'))
  data = np.array(dso.query_vbs('app.Acquisition.C1.Out.Result.DataArray'))
  </code></pre>
  <p>I've also tried <code>dso.write_vbs</code>, and removing the <code>np.array()</code>. But none of these work. The first line doesn't return any variable, the second returns a <code>str544</code> with value <code>ndarray object of numpy module</code> and the third returns a <code>str</code> with value <code>Cannot convert Variant to string</code>. I don't know what to do from here. How can I retrieve the waveform data?</p>