Biopac markers and triggers

[Paul Gr]

hi tony,

BioPac only supports recording of a set of digital input lines. The required 
digital signals can be generated by sending 8-bit values to the parallel 
printer port. Since BioPac records each bit as a separate channel, it is 
custom to use values that are a power of two to mark specific events. A 
related post is available at the list server: 
http://listserv.linguistlist.org/cgi-bin/wa?A2=ind0501d&L=eprime&P=219

Automatically starting acquisition (i.e. triggering) is just a matter of 
connecting and activating the correct digital line. I think BioPac currently 
offers a special EPrime compatible cable, which can be connected between the 
printer port and the STP100. (Note sure if this cable supports the trigger 
line. You could connect the trigger input with one of the other digital 
inputs [d8..d15] though.)

Note that the digital input channels are unrelated to the textual ‘Markers’ 
that are used in AcqKnowledge to mark events. You will require special 
offline software to translate the digital channels to biopac markers. 
(Although I don’t think those markers are very useful because AcqKnowledge 
doesn’t offer much functionality such as conditional epoching or averaging 
by using event markers.)

best,
Paul Groot

Vrije Universiteit van Amsterdam

>From: wells at mail.utexas.edu
>To: eprime at mail.talkbank.org
>Subject: Biopac markers and triggers
>Date: Thu, 07 Sep 2006 16:10:48 -0500
>
>How can I send markers and triggers to Biopac?  That is, should there be an
>inline object that sends the marker or trigger?  If so, what should be in 
>it?
>
>Just to make sure I'm being clear... by "marker" I mean just sending a 
>marker to
>Biopac to mark when something has happened.  By "trigger" I mean letting 
>Biopac
>know when to start and stop recording.
>
>Also, if it helps we're using Biopac systems MP150 with a STP100C 
>interface.
>Thanks!
>
>   - Tony Wells
>
>
>
>