Keyboard Calibration Using the Damn Laser

saturn — Thu, 09 Mar 2017 00:04:34 +0000

Almost no one care about how precise/reliable the keyboard pressing is, here, we built a damn cool equipment to examine this question. Broadly speaking, the time precision is good, mean variance is less than 0.2 ms.

Environment: MATLAB with Linux (Ubuntu 14.04)

Monitor: SONY Triniton at 120Hz

Keyboard: Mechanic number board

In short, the delay is about 12 ms and the variation is quite small.

Tips to get USB keyboard index in Matlab while using KbQueueCheck

saturn — Tue, 22 Nov 2016 23:55:58 +0000

A keyboard index is necessary when using KbQueueCheck instead of KbCheck. So how to get a valid keyboard index of your desired USB keyboard?

Credit: Jacob M. Paul in our lab.

[Linux enviroment]

1. Check if the keyboard was recognized by the system.

Steps: Plug in your USB keyboard -> Open Terminal -> Input “lsusb“ -> Plug off the USB keyboard -> Input “lsusb“ again in Terminal

Check if there were changes in the list. Here we can recognize a change of “Itron Technology tOne”, which is our USB keyboard. This means that the keyboard can be recognized by the system.

2 Get index in MATLAB

Steps: Plug off the USB keyboard -> Open MATLAB -> Input “[id names info] = GetKeyboardIndeces()”

MATLAB will give out some ids etc… Note that there are only 3, 4, 5 and 7 for now.

Steps: Plug in the USB keyboard -> Reopen MATLAB (important) -> Input “[id names info] = GetKeyboardIndeces() again”

Note that there are extra id: 8, 9, and 10.

3 Try these three indices in KbQueueCheck.

Here, the keyboard index for our USB keyboard is 10.

keyboard – Dr. Jian Chen

Keyboard Calibration Using the Damn Laser

Tips to get USB keyboard index in Matlab while using KbQueueCheck