TCP/IP connection problems

Siriusy commented 5 years ago

I try to use Pyvisa and Pyvisa-py to control several instruments through Ethernet. Everything works well except an Anritsu Signal Generator named MG3694C. I got the error :

[Command: python3 -u /home/quantum/Downloads/MG3694C.py]
Traceback (most recent call last):
  File "/home/quantum/Downloads/MG3694C.py", line 11, in <module>
    print(inst.query('*IDN?'))
  File "/usr/local/lib/python3.6/dist-packages/pyvisa/resources/messagebased.py", line 558, in query
    self.write(message)
  File "/usr/local/lib/python3.6/dist-packages/pyvisa/resources/messagebased.py", line 223, in write
    count = self.write_raw(message.encode(enco))
  File "/usr/local/lib/python3.6/dist-packages/pyvisa/resources/messagebased.py", line 201, in write_raw
    return self.visalib.write(self.session, message)
  File "/usr/local/lib/python3.6/dist-packages/pyvisa-py/highlevel.py", line 373, in write
    raise errors.VisaIOError(ret[1])
pyvisa.errors.VisaIOError: VI_ERROR_IO (-1073807298): Could not perform operation because of I/O error.

My code is simple, and the same code (different address) works well to all other instruments :

import visa
import numpy as np
rm = visa.ResourceManager('@py')
ipaddr = 'TCPIP0::192.168.0.254::INSTR'
inst = rm.get_instrument(ipaddr)
print(inst.query('*IDN?'))

I spent a lot of time searching online try to find a solution, but failed. The problem seems to be in the buffer size, like in https://github.com/pyvisa/pyvisa/issues/174. However, the definition of the set_buffer function in pyvisa-py seems has not been finished. As follow:

#/usr/local/lib/python3.6/dist-packages/pyvisa/highlevel.py
def set_buffer(self, session, mask, size):
    """Sets the size for the formatted I/O and/or low-level I/O communication buffer(s).

    Corresponds to viSetBuf function of the VISA library.

    :param session: Unique logical identifier to a session.
    :param mask: Specifies the type of buffer. (Constants.VI_READ_BUF, .VI_WRITE_BUF, .VI_IO_IN_BUF, .VI_IO_OUT_BUF)
    :param size: The size to be set for the specified buffer(s).
    :return: return value of the library call.
    :rtype: :class:`pyvisa.constants.StatusCode`
    """
    raise NotImplementedError

More details of my computer:

Machine Details:
   Platform ID:    Linux-4.15.0-39-generic-x86_64-with-Ubuntu-18.04-bionic
   Processor:      x86_64

Python:
   Implementation: CPython
   Executable:     /usr/bin/python3
   Version:        3.6.7
   Compiler:       GCC 8.2.0
   Bits:           64bit
   Build:          Oct 22 2018 11:32:17 (#default)
   Unicode:        UCS4

PyVISA Version: 1.10.0.dev0

Backends:
   ni:
      Version: 1.10.0.dev0 (bundled with PyVISA)
      Binary library: Not found
   py:
      Version: 0.3.1
      ASRL INSTR: Available via PySerial (3.4)
      USB INSTR: Available via PyUSB (1.0.2). Backend: libusb1
      USB RAW: Available via PyUSB (1.0.2). Backend: libusb1
      TCPIP INSTR: Available 
      TCPIP SOCKET: Available 
      GPIB INSTR:
         Please install linux-gpib to use this resource type.
         No module named 'gpib'

I'm new to visa. So how can I fix this issue? Can anyone help?

MatthieuDartiailh commented 5 years ago

Could you check the following on your instrument ?

the interface language used by the instrument is SCPI and not native (native is reserved for GPIB and even there I would not recommend it) (see the manual, link below, for details on how to set it)
your settings match the ones suggested in the instrument documentation (https://dl.cdn-anritsu.com/en-us/test-measurement/files/Manuals/Programming-Manual/10370-10375D.pdf) (obviously the IP can be different)

Siriusy commented 5 years ago

Thank you for your reply and manual.

To change the interface language of it from Native to SCPI can only be achieved by using a command, which also includes a writing process (i.e., write function). As a result, the error remains the same (I tried before).
To it, I find the python-vxi11 driver works well. Maybe the solution is not essential for me now, but i still want to know the answer. Thank you for your reply again.

MatthieuDartiailh commented 5 years ago

You can actually change the interface language from the instrument front panel (page 38 of the manual). Could you post a minimal script using python-vxi11 ? I will try to dive (once again) to see what might be done differently and hence cause the problem.

Siriusy commented 5 years ago

Thank you,

So it is! I tried it, but the error still exists.

the follow vxi11 code works well for me.

import vxi11
import numpy as np
inst = vxi11.Instrument('TCPIP0::192.168.0.254::INSTR')
print(inst.ask('*IDN?'))
inst.write('SYST:LANG "SCPI"')

The language setting is behind the ask function, hope may help you!

mnemocron commented 3 years ago

I came here because I switched from USB to Ethernet due to missing USB drivers for ARM (Raspberry Pi) from Keysight. So I am on the Raspberry Pi trying to connect to the Keysight 34465A without success.

@siriusy thank your for the hint with vxi11 this one works like a charm

@MatthieuDartiailh see my code below, maybe it helps for debugging

It is not the same error. I get Connection refused Note that I had to come up with the address 'TCPIP0::192.168.1.221::5000::SOCKET' myself, because I don't have a connection manager on the raspberry pi. The IP is correct and the Keysight manual states port 5000 as standard.

pyvisa 1.11.3
pyvisa-py 0.5.1
python 3.7.3

pyvisa variant

python3
Python 3.7.3 (default, Jul 25 2020, 13:03:44)
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import pyvisa as visa
>>> rm = visa.ResourceManager()
>>> ADR = 'TCPIP0::192.168.1.221::5000::SOCKET'
>>> dmm = rm.open_resource(ADR)
>>> dmm.query('*IDN?')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/pi/.local/lib/python3.7/site-packages/pyvisa/resources/messagebased.py", line 638, in query
    self.write(message)
  File "/home/pi/.local/lib/python3.7/site-packages/pyvisa/resources/messagebased.py", line 197, in write
    count = self.write_raw(message.encode(enco))
  File "/home/pi/.local/lib/python3.7/site-packages/pyvisa/resources/messagebased.py", line 157, in write_raw
    return self.visalib.write(self.session, message)[0]
  File "/home/pi/.local/lib/python3.7/site-packages/pyvisa_py/highlevel.py", line 543, in write
    written, status_code = self.sessions[session].write(data)
  File "/home/pi/.local/lib/python3.7/site-packages/pyvisa_py/tcpip.py", line 625, in write
    size = self.interface.send(block)
ConnectionRefusedError: [Errno 111] Connection refused

vxi11 variant

python3
Python 3.7.3 (default, Jul 25 2020, 13:03:44)
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import vxi11
>>> instr = '192.168.1.221'
>>> instr = vxi11.Instrument('192.168.1.221')
>>> print(instr.ask("*IDN?"))
Keysight Technologies,34465A,MY54505614,A.02.14-02.40-02.14-00.49-02-01

MatthieuDartiailh commented 3 years ago

Can you try the following ? This will be closer to the vxi11 example since INSTR resources on TCPIP uses the vxi11 protocol by default.

>>> import pyvisa
>>> rm = pyvisa.ResourceManager()
>>> dmm = rm.open_resource("TCPIP::192.168.1.221::INSTR")
>>> dmm.query('*IDN?')

mnemocron commented 3 years ago

Hey, that worked! Thank you :D

MatthieuDartiailh commented 3 years ago

Happy to help !

pyvisa / pyvisa-py

TCP/IP connection problems #261

pyvisa variant

vxi11 variant