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Chapter 8 SCSI Commands
The First Element Address Returned field is set to the smallest Element Address
agreeing with the requested Element Address in the CDB.
The Number of Elements Available field is set to the number of elements
agreeing with the requested Element Address in the CDB. If the Allocation
Length is sufficient, the status of these elements is also returned.
The Byte Count of Report Available field is set to the number of bytes necessary
to transfer the Element Status Page of all elements agreeing with the request by
the CDB. This value is never adjusted to match the Allocation Length.
8.12.2. Element status page
The Element Status Page is defined in table 8.12.2.1. Each Element Status Page
includes an 8-byte header and one or more succeeding Element Descriptor
Blocks. The header includes the Element Type Code, the length of each
Descriptor Block, and the number of bytes in the Element Descriptor
information following the header of the element Type.
Table 8.12.2.1 : Element status page
The Element Type Code field indicates the Element Type returned by this page.
The Primary Volume Tag (PVolTag) bit is the same as the one in the CDB. The
Alternate Volume Tag (AVOLTAG) bit is not supported by the autoloader,
therefore it is always 0.
The Element Descriptor Length field indicates the number of bytes in each
Element Descriptor.
The Byte Count of Descriptor Data Available field indicates the number of valid
Element Descriptor Data bytes of elements of the element Type agreeing with
the request by the CDB. This value is never adjusted to match the Allocation
Length.
Each Element Descriptor includes an Element Address and Status Flags. The
Status Flags also include Sense Code information similar to the information for
each Element Type.
Bit
Byte
7
6
5
4
3
2
1
0
0
Element type code
1
PVolTag AVolTag
Reserved
2
(MSB)
Element descriptor length
3
(LSB)
4
Reserved
5
(MSB)
Byte count of descriptor data available
(this page, n - 7)
6
7
(LSB)
8
Element descriptor(s)
n
