UT8805E Pyvisa Communication

[sysboy]

I also have a  UT8805E and this EOFError issue. It looks like the UT8805E doesn't pad the response to a multiple of 4 bytes. This is why some commands might work and others might not if the response is a multiple of 4 bytes. The underlying commands are working, pyvisa is just treating it as malformed as far as I can see. If I craft raw VXI commands it returns the data fine.

UT8805E firmware version: V1.87.014

$ pyvisa-info
Machine Details:
Platform ID: Linux-6.8.0-87-generic-x86_64-with-glibc2.39
Processor: x86_64

Python:
Implementation: CPython
Executable: .venv/bin/python3
Version: 3.12.3
Compiler: GCC 13.3.0
Architecture: ('x86', 64)
Build: Nov 6 2025 13:44:16 (#main)
Unicode: UCS4

PyVISA Version: 1.15.0

Backends:
ivi:
Version: 1.15.0 (bundled with PyVISA)
Binary library: Not found
py:
Version: 0.8.1
ASRL INSTR: Available via PySerial (3.5)
USB INSTR: Available via PyUSB (1.3.1). Backend: libusb1
USB RAW: Available via PyUSB (1.3.1). Backend: libusb1
TCPIP INSTR: Available
Resource discovery:
- VXI-11: ok
- hislip: ok
VICP INSTR: Available
TCPIP SOCKET: Available
PRLGX_TCPIP INTFC: Available
PRLGX_ASRL INTFC: Available via PySerial (3.5)

[sysboy]

I logged a ticket with Uni-T support and they gave me a new firmware release that fixed this issue.

The new working firmware is V1.87.017.

It now pads the 4 byte alignment correctly and works with pyvisa, at least for my simple tests.

[santo_13]

FYI - if you're not using any NI product - licensed software or hardware, you need a license to use NI-VISA, though not enforced, but legally compliant.

NI-VISA Deployment Licensing - NI

[sysboy]

Santosh,

I can't comment on the NI-VISA backend compatibility, it may or may not work, this was just about the pyvisa-py issue that the original poster had. Pyvisa-py enforces the XDR standards that Uni-T were not following.

https://github.com/pyvisa/pyvisa-py

Cheers

  Steve

[jomosoft]

Where can I find this firmware ? Only see version 014 on their website ?

[sysboy]

Their engineer sent it to me via email. I guess they will release it publicly soon?

[jomosoft]

Oke, I’ll keep an eye on it unless you don’t mind sending it to me (jomosoft@yahoo.com) ? 

[sysboy]

✔️