13
2 Initialize Element Status—07h
Command Description
The
INITIALIZE ELEMENT STATUS
command instructs the library to take an inventory if its
elements. The library does this by moving the tape picker across the front of the data
cartridge magazine. The tape picker houses an inventory sensor, which collects
element status information. If a bar code reader is installed in the library, it scans the
bar codes of the cartridges as part of the element status inventory.
The library stores the element status information in nonvolatile RAM. It sends the
element status information to an initiator in response to the
READ ELEMENT STATUS
command.
Note:
The library automatically performs and stores an element inventory
upon power-up, as well as each time the library’s front door is
opened and closed. Element status information is also updated
when the tape picker moves media from one element to another.
If a cartridge is in Drive 2 when the library takes inventory, its bar code cannot be
scanned. The library indicates this condition by setting an
EXCEPT
bit in the drive’s
element descriptor to indicate that the drive is in an abnormal state. See
Chapter 10.
Read Element Status—B8h
for details.
The library returns no data to the
INITIALIZE ELEMENT STATUS
command. To get information on
the status of elements, issue a
READ ELEMENT STATUS
command.
Table 2-1: Initialize Element Status Command—07h
Byte
Bit
7
6
5
4
3
2
1
0
00
Operation code—07h
01
Logical Unit Number (0h)
Reserved
02
Reserved
03
Reserved
04
Reserved
05
0
0
Reserved
0
0
