# OS9 Psychtoolbox 2.55 released

**URL:** <https://psychtoolbox.discourse.group/t/os9-psychtoolbox-2-55-released/672>\
**Category:** Uncategorized\
**Created:** [March 12, 2005, 10:46pm UTC](https://psychtoolbox.discourse.group/t/os9-psychtoolbox-2-55-released/672 "2005-03-12T22:46:45Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![denispelli](https://avatars.discourse-cdn.com/v4/letter/d/cdc98d/32.png) [@denispelli](https://psychtoolbox.discourse.group/u/denispelli)\
**Post date:** [March 12, 2005, 10:46pm UTC](https://psychtoolbox.discourse.group/t/os9-psychtoolbox-2-55-released/672/1 "2005-03-12T22:46:45Z")

</div>

Hi all  
  
OS9 Psychtoolbox 2.55 has been released. This is a minor update, fixing   
the bugs reported since the release of 2.54 on March 6. We recommend   
that all users of the OS9 Psychtoolbox upgrade to this new version.  
[http://psychtoolbox.org/download.html#os9](http://psychtoolbox.org/download.html#os9)  
  
Changes:  
- Incorporated Frans Cornelissen's fix for a bug in AssertMex. This   
fixes a bug in DescribeScreen.  
- Deleted Gestalt.m from OS9 Psychtoolbox since it is superfluous to   
Matlab 5's GESTALT, yet would interfere if the path places the   
Psychtoolbox ahead of Matlab's toolbox, as reported by Frans   
Cornelissen.  
- Updated help text in Snd.  
- Throughout the whole Psychtoolbox, now consistently refer to this   
version as "OS9". We used to refer to it as the "Mac" version, which   
has become ambiguous.