@larsoner is it possible to add an EDF version using the gist here: https://gist.github.com/skjerns/bc660ef59dca0dbd53f00ed38c42f6be

This would just create a fake EEG data with the corresponding electrodes in sample_ecog.mat.

Reason:
The reason is that inside mne-bids, right now the package needs an EEG file to be in an accepted "rawfile" format when performing writing. For EEG/MEG, these are readily available, but for iEEG this is only in the form of EDF and BV. This isn't an issue when using the existing EDF/BV datasets in mne, but none have electrode coordinates (i.e. a montage). The sample_ecog.mat here has a montage, but no corresponding iEEG data.

To make a good iEEG example in mne-bids, it would be helpful instead to just get a fake EDF file that has the same data as in sample_ecog.mat, and then sample_ecog.mat has the fake electrode coordinates.

Reference issues:

• Why does MNE-BIDS always need the raw.filename attribute? mne-bids#404
• [MRG] Adding updated unit tests and read_raw_bids correction for electrode coordinates (in meters) mne-bids#390