You can use conversion tables to convert data obtained from the main file or from any of the step-loop files or BAPI-table files. The conversion is performed at field level. To do such, place on "ABAP/CODE/HERE" column and double-click on a field to build a conversion table for that field. Then, build the table with the possible values the field may take(*), and the values that must enter to SAP for each case. For example, if you have a "City" field and you must convert it to the corresponding city code, a conversion table may be as follows:

@ 'New York' 'NY'
@ 'Buenos Aires' 'BA'
@ 'Rio de Janeiro' 'RJ'

 The "@" symbol must be always followed by a blank space (because another "@" symbol not followed by a blank space might be used to reach a remote database using EXEC SQL).

(*) Any value that may appear and not comprised in the table will not be converted.