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Timing issues with parallel port triggers

OS (e.g. Win10): Win 10
PsychoPy version (e.g. 1.84.x): v2020.2.5
Standard Standalone? (y/n) If not then what?: Y
What are you trying to achieve?:

I am trying to coordinate psychopy components (i.e., images shown on the screen, keyboard responses, etc.) with an intan recording controller via parallel port triggers sent through psychopy. This works fairly well except for two issues that have come up in a number of different experiments I have programmed.

  1. The port triggers always start at the correct time for all stimulus events but their duration is highly variable. For example, a trigger that is supposed to only last 1 frame will instead last 3. I have also done in units of time instead of frames and had similar results. It is especially bad with shorter durations.

  2. The port triggers that are sent as soon as the participant responds are different than the recorded RT by psychopy. In other words, if I program the port to trigger right when a participant responds via the keyboard, the intan does no register the port firing until 30-50 ms after the key response is made.

I have set up the port triggers to be sent via the port component and code component and both of these issues persist. I have also tried stripped down experiments where there are less stimuli that need to be loaded and found no improvement. Do others have experience with this issue? Thank you in advance for your help.