Seagate ST3285N, Руководство по эксплуатации продукта

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3.4.9 Inquiry command (12
H
)
When the drive receives the inquiry command, it asserts the data-in
phase and sends 68 bytes of inquiry data to the initiator. When the
requested inquiry data cannot be returned, a check condition status is
reported. After the data has been transferred to the initiator, the drive
deasserts the data-in phase.
If an Inquiry command is received from an initiator with a pending
unit-attention condition (before the drive reports a check condition
status), the drive performs the Inquiry command and the Unit Attention
condition is not cleared.
The initiator should allocate 36
H
bytes for inquiry data. The inquiry data
returned to the initiator is summarized in Appendix D.
Bit
Byte
7 6 5 4 3 2 1 0
0 0 0 0 1 0 0 1 0
1
LUN
Reserved
EVPD
0 0 0 0
2
Page code
0 0 0 0 0 0 0 0
3 0 0 0 0 0 0 0 0
4 Allocation length, in bytes
5 0 0 0 0 0 0 Flag Link
Byte 1 If the
EVDP (Enable Vital Product Data) bit is zero, the drive
returns the standard inquiry data. If the EVDP bit is one, the drive
returns the optional vital product data specified in byte 2.
Byte 2 The page code field specifies which page of the vital product
information the drive returns.
Byte 4 The allocation length specifies the number of bytes the initiator
has allocated for returned inquiry data. An allocation length of 0
indicates that no inquiry data is transferred. This condition is not
considered an error. Any other value indicates the maximum
number of bytes to be transferred. The allocation length should
be at least 36
H
to allow the initiator to receive all of the inquiry
data.
ST3655 Family SCSI Drives Product Manual, Rev. A 47