JavierD - MSFT
That is correct. BDC does not provide any conversion functionality.
BDC allows you to model external data (usually a backend system) and make the data accsesible in SharePoint.
In the BDC application definition file you will describe the external data system:
Define the data objects (entities)
Define methods like find specific, finder, etc. (These map to web method calls or calls to ADO .NET)
Set the authentication properties
And other settings
Then the BDC webparts using the BDC runtime will execute methods like finder to fetch the data form the external data system.
Other webparts like list may also consume these BDC applications.
You can always create your code and use the runtime for custom parts / actions.
These are just few of the features that BDC offers, BDC does not provide data manipulation.
Javier