Scratchpad

 Traceback (most recent call last):
  File "./test_gpib_prologix.py", line 118, in <module>
    result0 = f.get("LAST? %d" % chan)
  File "./test_gpib_prologix.py", line 83, in get
    self.checkErr(cmd)
  File "./test_gpib_prologix.py", line 67, in checkErr
    raise IOError('Error for command string [' + cmd + "]:\nError " + repr(error) + ': ' + esrStatusBits.get(error, repr(error)))
 IOError: Error for command string [LAST? 0]:
 Error 4: Query error