Sony AIT-SDX560, Руководство по техническим характеристикам продукции

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REQUEST SENSE 7. ATAPI Packet Command Specification
SONY AIT-2 Turbo drive SDX-560V series Ver.1.0 7-55
Command Specific Information Bytes: Command Specific Bytes are unused, and will be ZERO.
Additional Sense Code and Additional Sense Code Qualifier: These two bytes provide additional information
about what caused the CHECK CONDITION status. They are used extensively by the drive. The information is
presented in the Sense Key Description table on the following pages.
Field Replaceable Unit Code: This byte is used to define a device specific mechanism or part that has failed. A
value of ZERO indicates that no specific mechanism or unit has been identified to have failed. The units and their
values are:
00h - Unable to identify failed unit
01h - Drive Mechanism
02h - Drive Electronics
Sense Key specific bytes: These fields will contain data that further defines the nature of the CHECK
CONDITION.
If the sense field is set to ILLEGAL REQUEST and the SKSV bit is set to one, the Sense Key specific fields will be
as shown below. The fields point to illegal parameters sent by the Host.
Table 7-55: Sense Key Specific Values
Bit
Byte
7 6 5 4 3 2 1 0
15 SKSV C/D Reserved Reserved BPV Bit Pointer
16 (MSB)
17
Field Pointer
(LSB)
C/D: When this bit is set, it indicates that the illegal parameter is in the Command Descriptor Block. A C/D bit of
ZERO indicates that the illegal parameter is in the data parameters sent by the Host.
BPV: The Bit Pointer Valid bit set, indicates that the value in the Bit Pointer field specifies which bit of the byte
designated by the Field Pointer field is in error. A BPV bit of ZERO indicates that the Bit Pointer field is not valid.
When a multiple-bit field is in error, the Bit Pointer field shall point to the most-significant (left-most) bit of the field.
Field Pointer: field indicates which byte of the CDB or of the parameter data was in error. Bytes are numbered
starting from zero, as shown in the tables describing the commands and parameters. When a multiple-byte field is
in error, the pointer shall point to the most significant (left-most) byte of the field.
If the Sense Key is RECOVERED ERROR, HARDWARE ERROR or MEDIUM ERROR and if the SKSV bit is one,
the Field Pointer field returns implementation-specific information on the actual number of retries of the recovery
algorithm used in attempting to recover an error or exception condition.
Deferred Errors
Error code 70h indicates that the “Check Condition” status returned is the result of an error or exception condition
on the I/O process that returned the “Check Condition” status. This includes errors generated during execution of
the command by the actual execution process. It also includes errors not related to any command that are first
observed during execution of a command. Examples of this latter type of error include a servo-mechanism, off-
track errors, and power-up test errors.
Error code 71h (deferred error) indicates that the “Check Condition” status returned is the result of an error or
exception condition that occurred during execution of a previous command for which “Good” status has already
been returned. Such commands are associated with use of the Immediate bit, with some forms of caching, and
with multiple command buffering. Devices that implement these features are required to implement deferred error
reporting.