Event triggers not communicating with MP150 BIOPAC

[Bartz Lab]

Hi everyone,

I have a study where participants are presented with the same stimulus 3 times in E-prime. I'm recording their heart rate activity using a BIOPAC system while they complete the task. I've set up trigger signals in E-prime to mark the beginning of each of the 3 trials using the following code:

Slide1.OnsetSignalEnabled = True

Slide1.OnsetSignalPort = " &hD010"

Slide1.OnsetSignalData = 20

Slide1.OffsetSignalEnabled = True

Slide1.OffsetSignalPort = " &hD010"

Slide1.OffsetSignalData = 0

In AcqKnowledge, I've enabled all of the upper 8 digital lines (D8-D15). For some reason, only the first stimulus presentation is successfully marked with an event marker. After trying out multiple combinations of trigger signals in E-Prime (by making each stimulus have a unique trigger signal), I was only able to successfully mark 2 of the 3 stimuli in AcqKnowledge.

I've verified that my Parallel Port is working properly and that everything is connected properly.

Any insights into what might be going on would be greatly appreciated!!

Sonia