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PsychHID-ERROR warnings in PsychoPy v3.1.2

OS: MacOS Mojave 10.14.4
PsychoPy version: 3.1.2
Standard Standalone? (y/n) : y

I went from v3.0.7 to v3.1.2 and I have the following error after each experiment I run that was build in the Builder, also the demos:

Running: /Users/…/data/PsychoPy3 Demos/keyNameFinder/keyNameFinder_lastrun.py
PsychHID-ERROR: Could not enumerate and attach to all HID devices (HIDBuildDeviceList(0,0) failed)!
PsychHID-ERROR: One reason could be that some HID devices are already exclusively claimed by some 3rd party device drivers
PsychHID-ERROR: or applications. I will now retry to only claim control of a hopefully safe subset of devices like standard
PsychHID-ERROR: keyboards, mice, gamepads and supported USB-DAQ devices and other vendor defined devices and hope this goes better…
PsychHID-INFO: That worked. A subset of regular mouse, keyboard etc. input devices and maybe some vendor defined devices will be available at least.
2019-05-29 09:47:43.691 python[38196:3836099] ApplePersistenceIgnoreState: Existing state will not be touched. New state will be written to (null)

My question: the scripts are running despite the error, though should I worry about it? How can I resolve it?

Many thanks!

The warning is coming from psychtoolbox code that we recently switched to for better keyboard response timing. If the device that you’re using to get key presses is working then this is probably no problem.

Out of interest, what USB devices do you have connected (button boxes etc)?

Hi @jon,

Thanks for the reply! I was running this script from a MacBook pro (2018 edition) and was just using the keyboard. No button boxes, extra mouse or keyboard attached.

Very weird then, but I think it’s just annoying not a problem (assuming your keyboard responses are working - maybe try the demos>input>keyboardNEW in the Coder view).

Does your macbook have one of those TouchBars? Maybe that’s the device that psychtoolbox is complaining about. If not then I’m out of ideas I’m afraid.

Yes, using that demo the keyboard seems to work fine! Also (purposely) no touch bar! So it indeed seems to not be an actual problem.

Thank you!

Out of curiosity. Is the keyboard of a laptop interfaced with a USB like interface or through some other bus?

Macs at least use internal USB for keyboard, trackpad, camera, & flash card reader if it has one.

I know in the past that this sometimes influenced what external USB port to connect equipment to, because they could be connected to different internal buses that could be under quite different loads. eg a port on the same bus as the camera could be under a higher load, and could cause dropouts when connecting audio equipment for example, while the other port might be under little conflicting load at all.