Build a simple web service to run a MSSQL sp

I need a web service that runs a storedprocedure in mssql 2008 r2 and returns the numeric code that the sp returns (small integer). this web service only needs to get triggered without recieving information from the one consuming it. the only data it will return is a small integer from the database. The database conection info must be editable without affecting the code ([login to view URL] or something like that).