Hello Jason,
Thanks again for your timely reply! I have discovered the issue. We have been sending ttl signals unknowingly. The parameter used is <value> and it properly sends a trigger to our program at the onset of the stimulus. However, oddly, despite not having placed any location or duration it seems to work just fine. Once I do enter a value and a duration for instance <1:9600:5>, Media Lab no longer sends the signal. My question is, how would I determine what serial port location I will be sending the ttl signal to? Somehow just <1> works, but when I try to enter a value for the location, which I believe is either 9600, or 19200 based on this image of our virtual serial port emulator, the ttl signal no longer sends.medialab img.gif
Again, your responses have been incredibly helpful and I can't stress enough how much I appreciate them!
Alex