[bug?]button box interaction with KbQueue

1

To whom it may concern,


I have two button boxes (Curdes) to be used in an MRI scanner. I have a memory paradigm coded using PTB 3.0.14 - Flavor:  - Corresponds to SVN Revision (MATLAB 2018b). For this paradigm, I have 5 keys (from button boxes) plus an experimenter pulse key ('p' on the keyboard) being listened by a KbQueue. The same script runs no problem on Windows. However, on Ubuntu Linux 16.04, which I am currently using for better timing, the button boxes are treated as separate device and calling KbQueuexxx([],key_list) will only listen to the keyboard but not the button boxes. However, when I use KbCheck, the button boxes are recognized.


For some reason KbQueue seems to think the button boxes' keys are different from the keyboard keys while KbCheck thinks they are the same.


HY

Western University

2
You did not say how you use KbCheck. If you do KbCheck(-1), it will read all keyboards. The KbQueueXXX functions can distinguish different keyboards under Linux and MAC. It is more powerful in theory, but it gives inconvenience practically, since we rarely need to know which keyboard the response is from.

So what you experiencing is not bug, but a feature under Linux :)

-Xiangrui