Zaptel API documentation?

Is there any documentation available for Zaptel device driver?

For example, I have a Wildcard TE205P.

How would I open an HDLC channel on a DS1/DS0 combination?
How would I write HDLC farmes to that channel?
How would I read HDLC frames?

How can I read and write raw data from a DS0?

Thanks for any and all help.