If you are using a CICS-supplied interface to invoke an adapter service, it might be necessary to perform data conversion in the CICS® Service Flow Runtime routing region utilizing a customized version of the standard CICS conversion table, DFHCNV.
A data conversion table could be needed if the CICS system is using ISC to communicate with a member of the CICS family that runs on a hardware platform that does not use EBCDIC. The conversion table defines how data is to be changed from ASCII format at the workstation to EBCDIC format in CICS.
ECI applications use the facilities of the CICS mirror program to call the CICS data conversion program, DFHCCNV, passing the request and reply messages found in the COMMAREA. DFHCCNV performs the necessary conversion of the COMMAREA as defined in the customized conversion table, DFHCNV. It applies standard conversion to those fields in the conversion templates for which nonstandard, user-handled conversion is not specified.
If DFHCCNV finds a conversion template in the DFHCNV table that matches the runtime initial program name (the DPL Stub program name of DFHMADPL or DPL Passthrough Stub program name of DFHMADPP), it performs code page translation and data conversion for the COMMAREA associated with the ECI request. A conversion template is a table entry defining fields in a data area that should be converted, and the conversion method to be applied to each field.
The conversion template must specify:
See Conversion templates for samples of the runtime conversion templates for DFHMADPL and DFHMADPP.
The SRVERCP keyword on the DFHCNV TYPE=ENTRY macro determines the server code page in which character data associated with the specified resource is encoded in the z/OS server. Such data is assumed to be encoded in EBCDIC.
The CLINTCP keyword on the DFHCNV TYPE=ENTRY macro determines the default client code page in which the character data associated with the specified resource is encoded when it is received by or sent from the z/OS server. In general, such data is assumed to be encoded in ASCII. However, the data could be encoded in EBCDIC; for example, for data passed through the CICS Web Server Plug-in. In this case, the client and server code pages are likely to be different, even though both are EBCDIC.
For information on how to install and configure DFHCNV, see Setting up data conversion.