Need some help/w scpi, python

Technical
1

I have an Ubuntu system onto which is installed python3, and pyvisa and the Keysight IO libs. And I have a SIGGEN device connected to it via ethernet. I can ping the SIGGEN and I can bring up a browser web page for it and execute the *IDN? SCPI command ok thru the web page.

This is the screen shot from the OEM web page to the instrument showing a simple SCPI command:

image
image711×632 38.3 KB

But I can’t get a simple find devices python script to find anything, namely this seemingly innocuous script:

import pyvisa as visa
rm = visa.ResourceManager()
rm.list_resources() # this just prints out an empty array, no errors though

This is the output from python3 -m visa info:

root@docker-desktop:/# python3 -m visa info
/usr/local/lib/python3.6/dist-packages/visa.py:23: FutureWarning: The visa module provided by PyVISA is being deprecated. You can replace `import visa` by `import pyvisa as visa` to achieve the same effect.
 
The reason for the deprecation is the possible conflict with the visa package provided by the https://github.com/visa-sdk/visa-python which can result in hard to debug situations.
  FutureWarning,
Machine Details:
   Platform ID:    Linux-4.19.76-linuxkit-x86_64-with-Ubuntu-18.04-bionic
   Processor:      x86_64
 
Python:
   Implementation: CPython
   Executable:     /usr/bin/python3
   Version:        3.6.9
   Compiler:       GCC 8.4.0
   Bits:           64bit
   Build:          Jan 26 2021 15:33:00 (#default)
   Unicode:        UCS4
 
PyVISA Version: 1.11.3
 
Backends:
   ivi:
      Version: 1.11.3 (bundled with PyVISA)
      Binary library: Not found
   py:
      Version: 0.5.2
      ASRL INSTR: Available via PySerial (3.5)
      USB INSTR: Available via PyUSB (1.2.1). Backend: N/A
      USB RAW: Available via PyUSB (1.2.1). Backend: N/A
      TCPIP INSTR: Available
      TCPIP SOCKET: Available
      GPIB INSTR:
         Please install linux-gpib (Linux) or gpib-ctypes (Windows, Linux) to use this resource type. Note that installing gpib-ctypes will give you access to a broader range of funcionality.
         No module named 'gpib'

Any idea what else I can do to try to get the program to recognize anything?
I also tried another simple find devices script taken from the Keysight IO library Python examples, which tries different search instrument strings when getting the resourcemanager, but this is what it reports:
r

oot@docker-desktop:/# python3 finddevices.py
Find all devices and interfaces:
 
Find with search string '?*':
... didn't find anything!
Find with search string '?*INSTR':
... didn't find anything!
Find with search string 'PXI?*INSTR':
... didn't find anything!
Find with search string 'USB?*INSTR':
... didn't find anything!
Find with search string 'GPIB?*':
... didn't find anything!
Find with search string 'GPIB?*INTFC':
... didn't find anything!
Find with search string 'GPIB0?*INSTR':
... didn't find anything!
Find with search string 'TCPIP?*':
... didn't find anything!
Find with search string 'TCPIP?*SOCKET':
... didn't find anything!
Find with search string 'TCPIP?*inst?*INSTR':
... didn't find anything!
Find with search string 'TCPIP?*hislip?*INSTR':
... didn't find anything!
Find with search string 'ASRL?*INSTR':
... didn't find anything!
Done.
2

SOLVED (sort of)
Doing the following allowed us to get a response from the instrument using an SCPI command. We did not get a response from the resourceManager.list method, though.

  1. Removed the KeysightIO libraries
  2. Installed the pyvisa-py backend instead.
  3. Use the pyvisa resource manager’s open_resource and issuing a *IDN?

This is the code we used that gave us an IDN response:

import pyvisa as visa
rm = visa.ResourceManager()
rm.list_resources() # this doesnt print anything

SG1 = 'TCPIP::192.168.16.49::inst0::INSTR'
sgi = rm.open_resource(SG1)
# this prints out the line
# Agilent Technologies, N5182B, MY57301089, B.01.86
print(sgi.query("*IDN?"))
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