# Can Psychtoolbox DAQ support Parallel ports LPT1-LPT3 independently?

**URL:** <https://psychtoolbox.discourse.group/t/can-psychtoolbox-daq-support-parallel-ports-lpt1-lpt3-independently/1009>\
**Category:** Uncategorized\
**Created:** [February 19, 2009, 8:03pm UTC](https://psychtoolbox.discourse.group/t/can-psychtoolbox-daq-support-parallel-ports-lpt1-lpt3-independently/1009 "2009-02-19T20:03:53Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**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:** [February 19, 2009, 8:03pm UTC](https://psychtoolbox.discourse.group/t/can-psychtoolbox-daq-support-parallel-ports-lpt1-lpt3-independently/1009/1 "2009-02-19T20:03:53Z")

</div>

Dear Friends,  
  
For the Psychtoolbox DAQ module,we come across a problem.For normal PC,  
in doing psychological experiments,we use the Parallel port to send   
signals to drive LEDs,there are only eight data line available,since we   
want to present more stimuli and controlling the timing   
independently,this covers more channels than a single LPT can   
fulfill,we are seeking to use two additional Parallel ports which   
should provide another 16 data channel,I wonder anyone has experienced   
this problem and kindly share the knowledge,is there some   
specific on hardware setting? it seems the PC can not recognize an   
additional port.  
  
The following is a simple script to open LPT1 and send a trigger.  
  
dio=digitalio('parallel','LPT1');  
addline(dio,0:7,'out');  
addline(dio,9:13,'in');  
  
putvalue(dio.Line(1:8),3);   
  
Thanks,  
John