# OS X – KbCheck with 2nd keyboard

**URL:** <https://psychtoolbox.discourse.group/t/os-x-kbcheck-with-2nd-keyboard/1657>\
**Category:** Uncategorized\
**Created:** [July 6, 2006, 1:00pm UTC](https://psychtoolbox.discourse.group/t/os-x-kbcheck-with-2nd-keyboard/1657 "2006-07-06T13:00:42Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Allen\_Ingling](https://avatars.discourse-cdn.com/v4/letter/a/a183cd/32.png) [@Allen\_Ingling](https://psychtoolbox.discourse.group/u/Allen_Ingling)\
**Post date:** [July 6, 2006, 1:00pm UTC](https://psychtoolbox.discourse.group/t/os-x-kbcheck-with-2nd-keyboard/1657/1 "2006-07-06T13:00:42Z")

</div>

We use "KbCheck" in a while loop to acquire our subject's responses.   
This is working fine as long as the response keyboard is device# 1 (as   
determined with "GetKeyboardIndices"). If we connect another keyboard   
and restart MatLab, it will be assigned another device#, e.g., 3. So we   
use "KbCheck(3)" to get the response from this keyboard. This is the   
bit that doesn't work - we do see the input in the matlab-command   
window, but do not pick the response up with "KbCheck(3)". Any help   
would be greatly appreciated.  
  
We are running PTB 1.0.6 with Matlab 7.1.0.183 (R14) on a G4 PowerPC   
(OS X 10.3.9)  
  
Best,  
Michael  
  
\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_  
Dr. rer. nat. Michael Hoffmann  
Visual Processing Lab  
Univ. - Augenklinik Magdeburg  
Leipziger Str. 44  
39120 Magdeburg  
Tel: 0049 (0)391 67 13585  
Fax: 0049 (0)391 67 13538  
\<[http://www.med.uni-magdeburg.de/fme/kauge/vpl/vpl\_hoffmann.html](http://www.med.uni-magdeburg.de/fme/kauge/vpl/vpl_hoffmann.html)\>