Peter, I own and use both Erwin (mainly for PowerBuilder) and an outstanding tool "EasyCase Professional - with the Database Engineer" complimentary product. Although EasyCase is expensive, it gives you: ERD's, DFD's, STC's, etc.
With the "Database Engineer" additional product it will reverse_engineer dbf's for sure, I do not know about the dbc, have never tried that.
The reverse engineering used to be part of EasyCase but they broke it out into a separate product obviously to gouge for more money. Anyhow, I prefer Erwin for PowerBuilder and EasyCase Professional fore EVERYTHING ELSE!!!