IBM System/360 System Programmer's Guide

Note: For output data sets, the system uses the contents of the block
count (BLKCT) field to write the block count in trailer labels when the
data control block is closed, or when the EOV macro-instruction is
issued. You must maintain the contents of this field yourself if the
system is to write the correct block count.
Device dependent portion of data control block when DEVD=PT and
DSORG=PS:
DCB r------T----------------------,
Address +16 ICODE I Reserved I
L ______ ~ ______________________ J
Device dependent portion of data control block when DEVD=PR and
DSORG=PS:
DCB r------T----------------------,
Address +16 IPRTSP I Reserved I
L ______ L __________ - ___________ J
Device dependE~nt portion of data control block when DEVD=PC or RD and
DSORG=PS:
DCB r-----------T-----------------,
Address +16 IMODE,STACK I Reserved I
L ___________ ~ _________________ J
The following parameters pertain to specific devices and may be
specified only when the DEVD parameter is specified.
KEYLEN=value
specifies, for direct-access devices, the length in bytes of the
The following parameters pertain to specific devices and may be
specified only when the DEVD parameter is specified.
KEYLEN=value
specifies, for direct-access devices, the length in bytes of the
key of a physical record, with a maximum value of 255. When a
block is read or written, the number of bytes transmitted is the
key length plus the record length.
CODE=value
specifies, for paper tape, the code in which records are punched as
follows:
Value
I
F
B
C
A
T
N
IBM BCD
Friden
Burroughs
National Cash Register
ASCII
Teletype
no conversion
(forrrat F records
only)
If this parameter is omitted, N is assumed.
DEN=value
specifies, for magnetic tape, the tape recording density in bits
per inch as follows:
Execute Channel Program (EXCP) Macro-Instruction 89

IBM System/360 Specifications

General

Brand	IBM
Model	System/360
Category	Desktop
Language	English