Operating instructions
19-2
SCSI REFERENCE 1012975
CHAPTER 19—REQUEST VOLUME ELEMENT ADDRESS (B5h)
19.1 ABOUT THIS COMMAND
The REQUEST VOLUME ELEMENT ADDRESS command requests that the
autoloader return the element descriptors created as a result of the SEND
VOLUME TAG (B6h) command. Data is returned in element address order. For
information about the SEND VOLUME TAG command, see Chapter 23.
Note: In a multi-initiator environment, you should reserve the entire autoloader
using the RESERVE (16h or 56h) command before you request element
descriptors. Do not issue the RELEASE (17h or 57h) command until after
you have successfully obtained data with the REQUEST VOLUME
ELEMENT ADDRESS command. You should issue commands in the
following order:
1. RESERVE (16h) for the entire autoloader
2. SEND VOLUME TAG (B6h)
3. REQUEST VOLUME ELEMENT ADDRESS (B5h)
4. RELEASE (17h)
19.2 WHAT YOU SEND TO THE AUTOLOADER
VolTag – Byte 01, Bit 4
This field indicates whether you want the autoloader to return the volume tag
(bar code label) information searched for by the SEND VOLUME TAG (B6h)
command. Volume tag information is obtained when the autoloader scans the
bar code label affixed to each cartridge in the autoloader. The valid values for
this field are as follows:
0 – Do not report volume tag information
1 – Report volume tag information
Note: For specifications for the bar code labels that can be used with the
autoloader, refer to the Exabyte Bar Code Specification for LTO Ultrium
Cartridges.
Element Type Code – Byte 01, Bits 3 through 0
This field specifies the element types you want the autoloader to report on.
The autoloader supports the following Element Type Codes:
0h – All element types
1h – Medium transport element (the carousel/cartridge loader)
2h – Storage element (the seven cartridge cells)
4h – Data transfer elements (the tape drive)
For an Element Type Code of 0h, the element types are reported in element
address order, beginning with the address specified in the Starting Element
Address field.
Note: If you specify element type code 3h, the autoloader returns Good status
and an Element Status header with all fields set to 00h.