any information on Natus files

Hi everyone! new to this forum, so greetings one and all...
I am currently trying to read some ECoG data acquired on
Natus system, and my objective is to use some open source, or
at least, develop some open source parsers for these files.
In the patient directory, I have files with extensions .eeg, .etc, .epo,
.stc, .snc etc.

My first question is, what kind of data do each of these files have?. And,
secondly, are there any freely distributed tools that I can use to read
them.
I would want to use them in Python or R, but this is not a hard preference.
I have
tried loadeeg.m from a website, and although it gives me sensible values
for the header etc, I get junk for the rest of the data.


So, I am open to any suggestions from the group.
Thanks,
Sid.

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