Spectra Logic Spectra 2k, Develop Manual

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Chapter 4. Inquiry—12h
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If the EVPD bit in the INQUIRY command is 0, the library returns standard INQUIRY data, as
show in Table 4-3. Values and meanings of field names in bold are further described in
Table 4-4.
Table 4-2: Inquiry Command Field Values
Field Name
Field Location
Values
Allowed
Meaning
Byte Bit
Logical Unit
Number
01 7-5
0h
Requests Peripheral Qualifier and Peripheral Device Type data for the
library itself. This is the only meaningful logical unit number.
Anything
else
Unlike other commands, a value other than 0h in this field does not
cause the library to return a CHECK CONDITION status. See
Peripheral Qualifier and Peripheral Device Type below.
EVPD
(Enable Vital
Product Data)
01 0 0
Requests the library to return only the standard inquiry data page. The
Page Code field is then ignored. The library does not support any Vital
Product Data pages.
Allocation
Length
04 All 00-FFh
Specifies the number of bytes the initiator allocates for data returned
from the inquiry command. Zero indicates no inquiry data is to be
transferred; this condition is not considered an error. The library
terminates the data in phase when it transfers either the number of
bytes specified by the allocation length field or all of the available
inquiry data, whichever is less. The data length for the standard
inquiry data returned by the library is 38h (56 bytes)
Table 4-3: Standard Inquiry Data Format
Byte
Bit
0 1 2 3 4 5 6 7
00 Peripheral Qualifier Peripheral Device Type
01 RMB Device Type Modifier
02 ISO Version ECMA Version ANSI-approved Version
03 AENC TRMIOP Reserved Response Data Format
04 Additional Length
05 Reserved
07 RelAdr WBus32 WBus16 Sync Linked Reserved CmdQue SftRe