As it is sometimes necessary to take account of POS-dependent factors during preparation of IDocs, and these factors may also be customer-dependent, function exits are defined in the POS interface. Once the system has prepared a record in a segment group, it allows you to modify the prepared data.

If you also want to transport additional field information to the POS systems, you can use segment E1WXX01 and supply data to this segment within the relevant function exit. There are further function exits for change pointer analysis, which allow POS outbound processing to react to this new field information.

The function exits are in function group XWPD. They are assigned as enhancement components of SAP enhancement WPDA0001. One or two predefined function exits are available for each of the eight POS interface objects:

SAP provides a predefined program code for the "Item" POS system, which you simply need to activate. However, the predefined routines adopt only the necessary field conversions of the individual segment groups. You must implement tasks that go further than this. You can copy the logging of any errors from the program samples that are supplied.

Note that you must also maintain the relevant conversion tables in Customizing for field conversions.

2. To activate the predefined SAP program code, you copy include program LXWPDF0x to ZXWPDU0x. The last x stands for a digit between 1 and 13, depending on which object in the above table should be activated. You can also implement further customer enhancements in include program ZXWPDU0x.

3. You can then create a customer project (for example, WPDA0001), maintain this with SAP enhancement WPDA0001 and then activate it.