Hello,
this is described very extensive in the adapter-documentation that comes with the adapter. However also on SCN you will find multiple blogs around EDI processing with these adapters/modules.
First I would recommend to browse through Prateeks (http://scn.sap.com/people/prateek.srivastava3)blogs,
for example the one about the Classifier/Splitter
They have been written long time ago but are very good.
Recently. I have also written a "Quick Setup" blog that describes the whole inbound processing (with an ANSI X12 example).
http://scn.sap.com/community/pi-and-soa-middleware/blog/2013/01/13/quick-setup
This should provide a good starting point.
Kind Regards