Toshiba MK6017MAP User Manual

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10.8.33.6.7 Data structure checksum

The data structure checksum is the two's complement of the sum of the first 511 bytes in the data structure.
Each byte shall be added with unsigned arithmetic, and overflow shall be ignored. The sum of all 512 bytes will
be zero when the checksum is correct. The checksum is placed in byte 511.

10.8.33.6.8 Self-test log sector

The following Table defines the 512 bytes that make up the SMART self-test log sector.

Self-test log data structure

Byte Descriptions

0-1

Self-test log data structure revision number

2-25

First descriptor entry

26-49

Second descriptor entry

..... ............

482-505

Twenty-first descriptor entry

506-507 Vendor

specific

508 Self-test

index

509-510 Reserved

511

Data structure checksum

10.8.33.6.9 Self-test log data structure revision number

The value of the self-test log data structure revision number is set to 0001h.

10.8.33.6.10 Self-test log descriptor entry

This log is viewed as a circular buffer. The first entry shall begin at byte 2, the second entry shall begin at byte
26, and so on until the twenty-second entry, that shall replace the first entry. Then, the twenty-third entry shall
replace the second entry, and so on. If fewer than 21 self-tests have been performed by the device, the unused
descriptor entries shall be filled with zeroes.

The content of the self-test descriptor entry is shown in the following Table.

Self-test log descriptor entry

Byte Descriptions

Content of the Sector Number

n+1

Content of the self-test execution status

n+2

Life timestamp (least significant byte).

n+3

Life timestamp (most significant byte).

n+4

Content of the self-test failure checkpoint

n+5

Failing LBA(least significant byte).

n+6

Failing LBA(next least significant byte).

n+7

Failing LBA(next most significant byte).

n+8

Failing LBA(most significant byte).

n+9 - n+23

Vendor specific.

Content of the Sector Number register shall be the content of the Sector Number register when the nth self-test
subcommand was issued.

Content of the self-test execution status byte shall be the content of the self-test execution status byte when the
nth self-test was completed

Life timestamp shall contain the power-on lifetime of the device in hours when the nth self-test subcommand was
completed.

Content of the self-test failure checkpoint byte shall be the content of the self-test failure checkpoint byte when
the nth self-test was completed.