DFM supports a DDM attribute called the coded character set identifier (CCSID). The CCSID attribute specifies an identifier registered with the IBM® Character Data Representation Architecture (CDRA) of an encoding scheme for coded character set data. The CCSID attribute is a 16-bit number identifying a specific set of encoding scheme identifier, character set identifiers, code page identifiers, and additional coding-related required information that uniquely identifies the coded graphic character representation used. For example, if a file has a CCSID of 437, it is in USA ASCII format. If it has a CCSID of 297, it is in the French EBCDIC format. The meaning of each CCSID is defined in the IBM CDRA. See Character Data Representation Architecture Reference and Registry and Character Data Representation Architecture Overview for more information.

All single-byte code page conversions supported by CDRA are supported. DFM provides built-in support for data conversions between code pages 500 and 850. CDRA needs to be activated for code page conversions that are outside the DFM built-in support range. The special PC code page values of 0 and 65535 prevent stream data conversion. These values are not valid with the TEXT parameter because not providing the PC code page makes it impossible to determine the delimiters that text processing requires. The special host code page value of 65535 (or BINARY) prevents stream data conversion.