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Missing parameters when sending triggers to EGI Net Station? (specs and cells)

[ Using Standalone PsychoPy, latest version, on Windows 7, 64 bits ]


We’re working on an experiment which requires sending triggers to an EGI Net Station (version 4.3), so we used de EGI package included within PsychoPy (PyNetstation).

Everything works fine, but the commands for sending triggers like:
ns.send_event( 'evt_', timestamp=egi.ms_localtime(), table = {'fld1' : 123, 'fld2' : "abc", 'fld3' : 0.042} )
are missing input values that should be sent to Net Station, for example, when sending the aforementioned trigger, Net Station’s event broser will properly “see” the key (as evt_), the tracks, and key codes (as the table's values), but the Specs and Cells fields are never filled with data.

By looking at the command’s documentation, say:
ns.send_event(key, timestamp=None, label=None, description=None, table=None, pad=False)

The only two other input values are Label and Pad (I’ve tested that Label works fine, too), so I don’t really see where could I add the Specs and Cells data to the trigger. When using PsychoPy’s shell I get some extra info about this command, but it doesn’t mention those two values neither.
I’ve read the simple, simple_distilled and multi examples, but none of them seems to include those values.

The main researcher here requires to send triggers with full data, so I would like to ask if there is any extra command to include the Specs and Cells values. Maybe I’m missing something. In case that this issue has been solved, it would be great to read an example of experiment adding the full data inputs to a trigger.

I’m attaching a screenshot of Net station’s event browser, os you can get a better idea of where those “Specs” and “Cells” values are supposed to be read.

Thanks in advance.
Best regards.

Sorry for the auto-post, I simply would like to bring more atention to this subject.

If I’m missing information that could make this question more approachable, please let me know.


This seems more like a question about the Net Station API rather than PsychoPy itself, which is probably why you aren’t getting an answer here. I’d direct this question towards Net Station support.

i.e. since PsychoPy is able to communicate with your EEG, you just need to find out the appropriate format of information to send it to populate the other fields. Unless there is an expert user of that system here, you probably need to ask elsewhere.

The specs and cell criteria are shortcuts generated by net station when the ECI events confirm to specifications defined for EGI’s original (now defunct) experiment control environment, EGIS. They are not mandatory but can make segmentation in Net Station easier. The Cell criteria is set up when the experiment includes a SESS event and a number of CELL events sent over at the beginning of the experiment. The keys defined for these events must match those given in the attached screen shot . The example is for an experiment with 4 cells (event conditions) The number of CELL events should match the number of cells in your experiment.

Specs is short for Trial Specifications and are generated when one and only one TRSP event is sent over at the end of each trial. The TRSP event must have a given set of keys but is open ended, more keys can be added after the default keys. An important consideration with the TRSP event, the cel#, obs# pair must be unique for each TRSP event. For example recording two runs of the same experiment in one file would violate this rule. below is an example of the default keys in the TRSP event. trl# is a global trail number, incremented for every trial, obs# is a cell-wise trail number. In the example, this is the third overall trial and the second observation of the fourth cell.

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