Communication with the trigger port: A beginner’s guide

by Dr. Robert Störmer
Head of Technical Support (Brain Products)

As soon as our active electrodes are used with our full band amplifiers, recording of clean EEG signals becomes as easy as pie. However, the acquisition of analog signals is only half the battle: The other half is the communication with the technical equipment involved. This includes:

  • the PC running the experiment control software
  • all kind of stimulators
  • MR-scanner gradient systems and many more.

The most accurate and reliable interfacing standard between all these components and EEG amplifiers is still the TTL protocol.

Beginners from non-technical disciplines are often challenged when setting up their experiment for the first time. There are different concepts, cables, protocols and terminology. The former Brain Products Technical Support Team member Clara Guenter therefore wrote a guide for exactly this audience and we are happy to make it available on our website.

Our recently released “Beginner’s guide on Communication with the trigger port” does not assume any previous technical knowledge and starts with the very basics, such as:

  • What is a digital port?
  • How does transistor-transistor logic work?
  • How do the digital port settings of our various amplifiers work?
  • How are the trigger bits evaluated and how do they appear in the marker file?

1. What is a digital port?
1.1. Transistor-transistor Logic (TTL) trigger levels
1.2. High active vs low active
1.3. Trigger Duration
1.4. Enable a trigger bit
1.5. Trigger Type
1.6. Debouncing
2. Marker file
3. Examples
4. Amplifier-specific Information
4.1. actiCHamp family
4.1.1. actiCHamp
4.1.2. actiCHamp Plus
4.2. BrainAmp family
4.3. LiveAmp
4.3.1. LiveAmp and Sensor Trigger Extension
4.4. V-Amp
4.5. TriggerBox
5. Summary

In case you have any questions, please do not hesitate to contact the Brain Products Technical Support Team at We are happy to provide you with more information and answer all remaining questions you may have.