Control Data Corporation 3300 Reference Manual page 276

FIELD NAME
IDM (ID Mode)
IDL (ID Length)
Status
ill
Location
Checksum
Device Number
Low Segment Limit
Segment Length
*
(reserved)
60229400
SIZE
1 bit
5
bits
1
character
2 characters
24 bits
3
characters
24 bits
4 characters
89
characters
DESCRIPTION
Type of record identification associated
with every record in file.
o
=
alphanumeric
1
=
numeric
Length in characters of record identification
field.
Reserved to reflect current status of the
file as defined by each operating system or
library program.
Starting character position of identification
field in each record of the file.
24-bit binary checksum of entire label.
This field is checked by I/O system· to
detect accidental modification of label.
Number of device on which this file segment
is stored. This field is checked against
device label to insure that proper packs are
mounted.
Binary hardware address at which this file
segment begins.
Number of allocatable units (tracks) in this
segment.
These fields are reserved for future use of
I/O system.
E-5