SFFSRC 

     SFFSRC is the surface file source. With this parameter, the type of
     data the can be contained in the file is specified.

     SFFSRC may be set to either decoded data (including UNKN, AIRW, 
     METR, SHIP, BUOY, and SYNP) or TEXT. If both types are requested,
     they are separated by a '|'. 
   
     The decoded file type MUST be specified first, otherwise a default
     to a text only file will be created.