When EMWTPCDE is set, this is a four-byte address of the descriptor
and route codes supplied by an authorized user to override the default
DESC (7 - task related) and ROUTCDE (11 - programmer information)
codes. The area can be mapped by EMWTDERT.
Parameter area (EMWTDERT) maps user-supplied descriptor and routing
codes that are contiguous areas as follows:
- Descriptor codes (EMWTDESC): A 16-bit field which has a bit on
for each descriptor code requested.
- Routing codes (EMWTRTCD): A 128-bit (16 byte) field which has
a bit on for each routing code requested.