Agilent DSO90804 infiniium scope times out on ":WAV:PRE?" query

In MAX:

if the timeout < ~3000 ms, query(:WAV:PRE?), times out. with timeout > ~5000 ms, this query is successful. Alternatively, if I do a gpib_write(:WAV:PRE?), manually wait a couple seconds and then '''gpib_read()''' in MAX or using the scope server, things are fine. Immediately reading after the write times out.

I attempted to use the timeout parameter, but this doesn't seem to actually set the timeout. I set gpib_query(':WAV:PRE?',timeout = 10.0) or gpib_query(':WAV:PRE?',timeout = 10000.0) and it still kicks back a timeout error in ~2-3 seconds.

Additionally, this behavior seems tied to the number of averages on the scope. Since the waveform preamble has little to do with the number of averages, I think this may just be the device taking a little longer to reply to the query while averaging or something else unrelated to my being able to actually set the query timeout.

scope = cxn.agilent_infiniium_oscilloscope
scope.select_device()
scope.averagemode('ON')
scope.get_trace(1)

the above works, and then:

scope.numavg(50)
scope.get_trace(1)

also works, but

scope.numavg(5=100)
scope.get_trace(1)

errors out with the following:

In [685]: scope.get_trace(1)
---------------------------------------------------------------------------
Error                                     Traceback (most recent call last)
<ipython-input-685-f55e13445fe5> in <module>()
----> 1 scope.get_trace(1)

C:\pylabrad\labrad\client.pyc in __call__(self, *args, **kw)
     63         if wrap:
     64             future.addCallback(lambda resp: resp[0][1])
---> 65         return future.wait() if wait else future
     66
     67     # data to be loaded on demand

C:\pylabrad\labrad\backend.pyc in wait(self)
    396                 # If any Future in the queue fails,
    397                 # we immediately bail.
--> 398                 result.raiseException()
    399             else:
    400                 for func, args, kw in f.callbacks:

C:\Python27\lib\site-packages\twisted\python\failure.pyc in raiseException(self)

Error: (0) [Agilent Infiniium Oscilloscope] Remote Traceback (most recent call l
ast):
Failure: labrad.types.Error: (0) [terminator GPIB Bus] Remote Traceback (most re
cent call last):
  File "C:\pylabrad\labrad\server.py", line 262, in handleRequest
    result = yield setting.handleRequest(self, c.data, data)
  File "gpib_server.py", line 194, in query
    ans = instr.read_raw()
  File "C:\Python27\lib\site-packages\pyvisa\resources\messagebased.py", line 28
1, in read_raw
    chunk, status = self.visalib.read(self.session, size)
  File "C:\Python27\lib\site-packages\pyvisa\ctwrapper\functions.py", line 1569,
 in read
    ret = library.viRead(session, buffer, count, byref(return_count))
  File "C:\Python27\lib\site-packages\pyvisa\ctwrapper\highlevel.py", line 145,
in _return_handler
    raise errors.VisaIOError(ret_value)
pyvisa.errors.VisaIOError: VI_ERROR_TMO (-1073807339): Timeout expired before op
eration completed.
 [payload=None]
 [payload=None]

labrad / servers

Agilent DSO90804 infiniium scope times out on ":WAV:PRE?" query #217