Incorrect trigger numbers

[Raphael]

We are running an experiment coded through psychopy and sending triggers by setting the parallel port to specific numbers. When viewing the recording on ActiView, it displays the correct trigger numbers on Decimal trigger format (e.g. 10, 11, etc.). However, when we load the bdf file on eeglab in Matlab, the trigger values show as 5-digit values (e.g. 16129, 16130, ..., 16383). We tried to run a simple code that will set the pins for each value ranging from 0 to 256. We set it to the value, wait 500ms, set it back to zero and wait another 500ms before sending the next trigger (https://imgur.com/a/zumqXQt). We are also attaching what we see under analog view, where the triggers 9-16 seem to constantly be set high, while trigger 1-8 are what's changing as we run the code (see link as well). Finally, we also attach a list of triggers exported from eeglab.

Can anyone see where the problem could be?

Thanks!

[Coen]

EEGLAB should be modified to show two 8-bit trigger codes (instead of one 16-bit)

OR

Connect trigger lines 9-16 (pin 9-16) to ground (pin 37)

Bets regards, Coen (BioSemi)