Method 14 for TCP to PC conversions
The method shown in Figure 66 has the following characteristics:
- See "Method 10 for EUC to PC Conversions" for a description of the type of table format used in this conversion method.
- It is used for conversion between an input TCP CCSID and an output PC CCSID
- The valid encoding scheme for input data is X'5404'. The valid output encoding schemes are X'2100', X'3100', X'2200', X'2300', X'2305', X'3200', and X'3300'
- Input is always expected in a normalized four-byte format, and it includes the identifier in the high-order byte indicating which coded graphic character set the code point was taken from.
- The conversion table created will handle either single-byte, double-byte, or triple-byte code points from the input CS, CP pair as defined by the TCP encoding scheme to a possible single-byte, or double-byte output CS, CP code point.
- Matched GCGID priority within a CS, CP
- Mismatch management criteria
- Space character management.
- For most TCP four-byte codes, only a certain range of values is valid for the three high-order bytes. To handle this situation, the table is organized as a series of subtables. Each subtable level points to a lower level subtable, until the last subtable level points to the actual output code point records. Each of the records contain 256 double-byte code point values.
- Invalid single-byte code points will be mapped into the single-byte character SUB, at code point X'7F'. All other invalid values will be mapped to the double-byte SUB character for the respective country version of the encoding scheme.
- Only a triple-byte CS, CP pair will use all four bytes of the input code point.
Figure 66. Method 14: TCP to PC Conversion