PLINK files too big

Hi,

I built a code in using pylink, the experiment is running OK but it outputs enormous EDF files.
5 min run -over 300MB. I tried opening the file to look inside but matlab crushes every time.

the code is here

Do you have any suggestions?
The eyelink is inside an MRI and I don’t have many opportunities to check it out.

Happy new year!
Nachshon