Visual P300 event markers not recorded about eeg-expy

[ErikBjare]

I think this is a duplicate of #108

Are the markers not appearing at all, or is the column just missing values initially?

[Maari13]

The column is missing values initially: starting from data row 13 (or row 14 of the file) until the end of the file the values are present. I was wondering whether I can trust that the values that are present are aligned with the correct timestamp, or the fact that the markers start from row 13/14 means that they are shifted in time - I mean the marker on row 14 should really be on row 2?

[ErikBjare]

I'm fairly confident that they are aligned, but @JohnGriffiths might have a more confident answer.

[JohnGriffiths]

I agree. The lsl process writes to file what is received on the the current stream at each time point. I'm not aware of any way it would buffer or otherwise delay the stream output. Especially from the markers stream, which is running locally (as opposed to the EEG stream, which operates on Bluetooth data packets that are known to have a minimum and a variable lag).

[rschmaelzle]

Hi, I can confirm this issue. I was able to track it down - in part - to the muselsl-record function, where there is an if-condition that has a "save every 5s"-comment. Messing with this "catches" more markers (although it doesn't yet cure my problem). Hope this helps. I will keep digging myself into it a bit more.

[tmorshed]

Closing to concatenate in #108.