User`s guide

2: BSCTRAN Commands and Options
DC 900-1406E 37
To send transparent 2780 records, BSCTRAN prefixes each
record with the count. Records are accumulated into the
BSCTRAN write buffer without splitting records. Blocks are
written to the ICP as command codes 22 and 23. The ICP
transmission block should be equal to or greater than the max-
imum record size + 2.
Note
The SEND /CARD option is not supported for transparent 2780.
To send non-transparent 2780 records, BSCTRAN handles
records in the same way as 3780, except that a Unit Separator
character (hex 1F) is inserted at the end of each record, rather
than a Record Separator (hex 1E).
In receive mode, BSCTRAN record handling is determined by
the command code. Command codes 22 and 23 signify trans-
parent 2780 records, each prefixed with a count. Command
codes 20 and 21 signify transparent data, usually 3780, but can
also be single-record transparent 2780 blocks. Command codes
16 and 17 signify non-transparent data, either 2780 or 3780.
BSCTRAN determines record boundaries by the RS or US
characters.
Refer to the BSC Programmer’s Guide for more information on
2780 and 3780 message blocking.
/BUFSIZE=n This option controls the size of the BSCTRAN write buffer and
the ICP message buffers. The default value for this option is
1024; the maximum value is 4096.