Request Volume Element Address (B5h)

Request Volume Element Address (B5h) returns the results of a previous Send Volume Tag command.

The returned data consists of an eight-byte Volume Element Address Header, followed by to four element pages (one page per element type). Each element page consists of an eight-byte Element Status Page Header, followed by the element type descriptor. Supported element type descriptors include:

Medium Transport Element Descriptor (same as Read Element Status)
Storage Element Descriptor (same as Read Element Status)
Import/Export Element Descriptor (same as Read Element Status)
Data Transfer Element Descriptor (DvcID = 0) (same as Read Element Status)
Data Transfer Element Descriptor (DvcID = 1) (same as Read Element Status)

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VolTag

0 = The library will not report Volume Tag information in the Element Descriptor data.

1 = The library will report Volume Tag information in the Element Descriptor data.

Starting Element Address

Specifies the minimum element address. The library reports elements with an element address greater than or equal to the Starting Element Address.

Number of Elements

The maximum number of element descriptors to transfer. This is not an element address range.

Allocation Length

The length in bytes of the space allocated by the initiator for the transfer of element descriptors. Only complete element descriptors are transferred. Data can be truncated based on the length specified in the allocation field.

Volume Element Address Header

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First Element Address Reported: The lowest element address found for the specified Element Type Code that is greater than or equal to the Starting Element Address.
Number of Elements Available: The number of elements found for the specified Element Type Codes that is greater than or equal to the Starting Element Address. This number is always less than or equal the Number of Elements.
Send Action Code: 5h = The action code from the previous Send Volume Tag command.
Byte Count of Report Available: The number of bytes of element status data available. This count does not include the Element Status Data header bytes. The count is not adjusted to match the allocation length you specified in the Read Element Status command.
Element Status Pages: These pages are in the same format as the Read Element Status (B8h) command pages. See Element Status Page Header and Element Descriptor Definitions.