Problem with trigger interface

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Posts: 1
Joined: Wed May 04, 2022 6:34 am

Problem with trigger interface

Post by joebathelt »

Hi Biosemi folks,
First of all, thank you for making such a fantastic product. Working with the EEG system and ActiView is usually a breeze. Unfortunately, some problems crept up last week that I find difficult to resolve.

The problem:
The problem is that the trigger channel on our receiver computer shows a constant signal in channel 3 and does not let any other triggers through. The signal stops when I shut down the stimulus computer but appears again when the stimulus computer is booting up.

What I tried already:
- checked all of the cables: all fine and the LEDs indicate that the system is working
- replaced the parallel port on the stimulus computer: did not make a difference
- swap stimulus and receiver computers (they are identical in our setup): did not make a difference

The system:
- ActiView 9.02
- Windows 10 Enterprise
- BioSemi system purchased before 2016
- Stimulus computer with a parallel port
- BioSemi receiver with a parallel port input and USB output

I'd be grateful for your suggestions on how to resolve the issue.

Thank you in advance for your help!


Posts: 24
Joined: Fri Sep 24, 2010 4:36 pm

Re: Problem with trigger interface

Post by Gerben »

Hi Joe,

What brand and model of the parallel port are you using?
And did this exact setup worked previously without problems?

If all the triggers are low with the stimulus computer off then the Biosemi USB receiver is working as it should.
So the problem is most likely within the stimulus computer or its parallel port,

On modern computers we recommend using our USB trigger interface to send triggers to the USB receiver because most modern computers come without a parallel port. ( ... 0cable.htm )

Best regards, Gerben (BioSemi)

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