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Chapter 8 SCSI Commands
The Send Action Code indicates a function specified by the SEND VOLUME
TAG command. In this command, results are returned based on the Send Action
Code.
8.17.1. Element status page
The Element Status Page is defined in the following table. Each Element Status
Page includes an 8-byte header and one or more succeeding Element Descriptor
Blocks. The header includes an Element Type Code, the length of each
Descriptor Block, and the number of bytes of Element Descriptor Information
following the Element Type header.
Table 8.17.1.1 : Element status page
The Element Type Code area includes the Element Type returned by this page.
A Primary Volume Tag (PvolTag) bit of 1 indicates that the following Element
Descriptor Block includes the Primary Volume Tag Information area.
A Primary Volume Tag (PvolTag) bit of 0 indicates that the Element Descriptor
Block does not include the Primary Volume Information area. When the value
is 0, the bytes are omitted from the Element Descriptor.
The Alternate Volume Tag (AVOLTAG) is not supported by the autoloader,
therefore it is always 0.
The Element Descriptor Length area indicates the number of bytes in each
Element Descriptor.
The Byte Count of Descriptor data available area indicates the number of bytes
in the valid Element Descriptor Data for Elements of Element Types matching
the condition requested in the CDB. This value is never adjusted to coincide
with the Allocation Length.
Each Element Descriptor includes the Element Address and Status Flags. These
include Element Type dependent information and sense codes.
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
