problem with triggers (again)

[Stephen D. Benning]

On Tue, 2004-07-06 at 10:57, Richard P. Heitz wrote:
> Hello,
>     A while back I brought up the issue of losing triggers with a NeuroScan
> EEG.  I've since switched to a new system, and I'm no longer losing
> triggers.  However, I still have the following problem.  I'm presenting some
> checkerboard patterns repetitively, and I'm trying to use the onsetsignal to
> mark the data.  The problem is that it only records the trigger the first
> time.  It seems like the computer only wants to record changes in pin
> values...since I'm signaling the same number over and over again, nothing
> changes except for the first signal.  I can get this to work if I send a
> value followed by another value, just to "reset" the pins.  Isn't there an
> easier way?

Not in a Neuroscan environment.  Neuroscan requires the port to be reset
back to a "hold" value to enable the next trigger to be delivered.
Based on what you've described as the structure of your program, I'd
suggest using the OffsetSiganl to reset your trigger port to the hold
value.

> ----------------------------------------------------------------------------
> ----------
> Richard P. Heitz, M.S.
> Attention and Working Memory Lab
> Georgia Institute of Technology, Atlanta Georgia 30332
> Email: gte016z at prism.gatech.edu
> Office: 350 J.S. Coon Building
> Web: http://psychology.gatech.edu/renglelab
--
Stephen D. Benning
Office: N631 Elliott Hall
75 East River Road
Minneapolis, MN  55455
E-mail: benn0224 at umn.edu