Hello everyone. I recently read a paragraph in BIOSEMI Manual as below:
'The built-in EEGLAB function that handles reading events from the Status channel is limited to data collected from ActiveTwo Mark I systems (all ActiveTwo systems up to about October or November, 2005). For data collected with Mark II systems, it is best to use the events derived by BIOSIG. For specific instructions on this, please consult the EEGLAB list and/or Alois Schloegl, the developer of BIOSIG'. (ActiveTwo Operating Guidelines, Page 64 of 78, Rev. 1, Printed: 5/19/2016)
I wonder whether the limitation with Mark II systems and higher versions of systems exists up until now? If it did, does it mean that all the trigger functions through systems other than Mark I perform wrongly for all the time?
Thanks for your attention and support!
BIOSEMI Trigger and EEGLAB reading events
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Re: BIOSEMI Trigger and EEGLAB reading events
ActiveTwo Mk1 and Mk2 (as well as the new ActiveThree) systems use exactly the same BDF file format (https://www.biosemi.com/faq/file_format.htm). In particular, storing of the 16 trigger lines in the Status channel is the same for all systems. The only difference between Mk1 and Mk2 files is the MSB in the Trigger/Status channel, which is used as Mk1/Mk2 indication (https://www.biosemi.com/faq/trigger_signals.htm). I would expect that EEGLAB only processes the 16 trigger bits in the Status channel and ignores the most significant Byte, and therefore does not see a difference between Mk1 and Mk2 files.
Best regards, Coen (BioSemi)
Best regards, Coen (BioSemi)