M2488 PRODUCT GUIDE MEDIA CHANGE R COMMANDS
March 1997 CG00000-011503 REV. A 6- 19
6-2.5 READ ELEMENT STA TUS MC command B 8h
The READ ELEMENT STATU S medium changer command requests that the ta rget report status
information for the medium-changer elements. Status for the elements is returned in blocks of bytes
called element descriptors, one descriptor per element.
This command can be used to determine which elements are defined and the state of each defined
element. The READ ELEMENT STATUS command is typ ically used pre ceding a MO VE MEDIUM
or EXCHANGE MEDIUM command to help determine if a move or exchange operation is possible.
6-2.5.1 READ ELEMENT STATUS CDB Des cription
READ ELEMENT STATUS is a twelve-byte command. The bytes are shown below and
described in Table 6-4. Common fields are described in paragraph 4-3.1 on page 4-4.
BITS
BYTES 7 6 5 4 3 2 1 0
010111000
1LUN Reserved Element Type Code
2-
3
MSB Starting Element Address LSB
4-
5
MSB Number of Elements LSB
6Reserved
7-
9
MSB Allocation Length LSB
10 Reserved
11 Reserved Flag Link
Note: Changeable fields in the CDB are shaded.