USB-Based instruments that do not appear to the host as a virtual com port (VCP) usually use libusb for communication. The pyvisa-py driver for pyvisa can communicate with these instruments. However, you must first create a udev rule (and possibly a user group.)

If you see the device in lsusb, but not the pyvisa ResourceManager, you need to add (or modify a udev rule):

# backup 99-com.rules (if it exists)
cp /etc/udev/rules.d/99-com.rules /etc/udev/rules.d/99-com.rules.BAK

# (create and) edit the file
nano /etc/udev/rules.d/99-com.rules

# Add the following line
SUBSYSTEM=="usb", MODE="0666", GROUP="usbusers"

# create a usbusers group
sudo groupadd usbusers

# add your account to the new group
sudo usermod -a -G usbusers USERNAME

# restart udev
/etc/init.d/udev restart
(Although, you are probably better off rebooting.)


Fan of making things beep, blink and fly. Created AddOhms. Stream on Twitch. Video Host on element14 Presents and writing for Hackster.IO. Call sign KN6FGY.

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