Incorrect Trigger Codes

[Peter Quain]

To start with, you can't send value of more than decimal 255 (8 bits, 
1 byte) using parallel port, and i think Neuroscan eq is setup to 
receive pulse values up to 255 (an 8 bit buffer). So when a parallel 
port device is added to the context, e-prime writeport command (and 
the send pulse on object onset function) must be geared to parse 
values (decimal or Hex) into a byte to send to the appropriate pins. 
The 'odd' values 118 and 777 appearing on the trigger channel 
probably result from e-prime trying to build a byte from 9 bits, but 
i can't see how a value of dec 777 can be sent at all, or represented 
in the neuroscan event channel.

Anyway, maybe change event codes within range 0-255 will fix it.

At 05:33 AM 27/05/2009, you wrote:

>I am using E-Prime to run an ERP experiment in conjunction with
>Neuroscan. Currently, Neuroscan is registering incorrect trigger codes
>for two events.
>
>In E-prime I have triggers for the following events in 4 conditions:
>
>NP1 (11, 22, 33, 44)
>
>Verb (1, 2, 3, 4)
>
>NP2 (111, 222, 333, 444)
>
>Right now, 333 and 444 are showing up in Neuroscan on the EEG as 118
>and 777 respectively. I have no idea why. I was wondering if it was
>because I copied and pasted the column codes into E-Prime from Excel,
>and those cells in Excel contained a formula (i.e., I had IF formulas
>for the respective codes to avoid errors).
>
>Has anyone experienced anything similar?
>
>Many thanks, Justine VanDyke,
>University of South Florida
>

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups "E-Prime" group.
To post to this group, send email to e-prime at googlegroups.com
To unsubscribe from this group, send email to e-prime+unsubscribe at googlegroups.com
For more options, visit this group at http://groups.google.com/group/e-prime?hl=en
-~----------~----~----~----~------~----~------~--~---