INQUIRY12h

INQUIRY tells the drive to return information about the basic operating parameters to the host. These parameters cannot be changed. The drive returns Inquiry data to the host in a data-in phase.

NOTE: This command is immune from most of the pre-execution checks that other commands must pass (for example, it can be executed while the unit is reserved for another host). Unit attention and deferred error conditions are preserved and reported on subsequent commands.

Pre-execution checks:

Only the Illegal Field Check is performed before the command is executed.

If the EVPD bit is clear, the page code must be zero, otherwise illegal request is reported.

If the EVPD bit is set, the page code must be one of the supported page codes for Inquiry data. Otherwise illegal request is reported.

Command descriptor block:

 

 

7

6

5

4

 

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

0

 

 

 

Operation

Code (12h)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

 

LUN

 

 

 

Reserved (0)

 

EVPD

 

 

 

 

 

 

 

 

 

 

 

 

2

 

 

 

Page Code

 

 

 

 

 

3

 

 

 

 

 

 

 

 

 

 

 

 

 

Allocation Length

 

 

 

 

4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5

 

 

 

Control

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CDB fields:

LUN

This field is ignored.

 

 

EVPD

Enable Vital Product Data

 

0

Normal inquiry data is returned.

 

1

A page of vital product data is returned.

 

 

 

Commands

INQUIRY 12h 39