265
Western Digital Hard Disk Drive OEM Specification
11.51.1.6
SMART Read Log Sector (Subcommand D5h)
This command returns the specified log sector contents to the host.
The 512 bytes data are returned at a command and the Sector Count value shall be set to one. The Sector Number
shall be set to specify the log sector address.
Log sector address
Content
Type
00h
Log directory
Read Only
01h
Summary SMART Error Log
Read Only
03h
Extended Comprehensive SMART Error Log
See Note
06h
SMART Self-test Log
Read Only
07h
Extended Self-test Log
See Note
09h
Selective self-test Log
Read/Write
80h-9Fh
Host vendor specific
Read/Write
Note: Log addresses 03h and 07h are used by the Read Log Ext and Write Log Ext commands. If these log addresses are used
w ith the SMART Read Log Sector command, the device shall return command aborted.
Table 229 Log sector addresses
11.51.1.7
SMART Write Log Sector (Subcommand D6h)
This command writes 512 bytes data to the specified log sector.
The 512 bytes data are transferred at a command and the Sector Count value shall be set to one. The Sector
Number shall be set to specify the log sector address (Table 229). If Read Only log sector is specified, the device
returns ABRT error.
11.51.1.8
SMART Enable Operations (Subcommand D8h)
This subcommand enables access to all SMART capabilities within the device. Prior to receipt of a SMART Enable
Operations subcommand, Attribute Values are neither monitored nor saved by the device. The state of SMART
(either enabled or disabled) will be preserved by the device across power cycles. Once enabled, the receipt of
subsequent SMART Enable Operations subcommands will not affect any of the Attribute Values.
Upon receipt of the SMART Enable Operations subcommand from the host, the device enables SMART capabilities
and functions, and then saves any updated Attribute Values to the Attribute Data sector.
11.51.1.9
SMART Disable Operations (Subcommand D9h)
This subcommand disables all SMART capabilities within the device including the device’s attribute autosave feature.
After receipt of this subcommand the device disables all SMART operations. Non self-preserved Attribute Values will
no longer be monitored. The state of SMART (either enabled or disabled) is preserved by the device across power
cycles.
Upon receipt of the SMART Disable Operations subcommand from the host, the device disables SMART capabilities
and functions, and then saves any updated Attribute Values to the Attribute Data sector.
After receipt of the device of the SMART Disable Operations subcommand from the host, all other SMART
subcommands
– with the exception of SMART Enable Operations – are disabled, and invalid and will be aborted by
the device (including the SMART Disable Operations subcommand), returning the error code as specified in Table
242 on the page 277.
Any Attribute Values accumulated and saved to volatile memory prior to receipt of the SMART Disable Operations
command will be preserved in the device’s Attribute Data Sectors. If the device is re-enabled, these Attribute Values
will be updated, as needed, upon receipt of a SMART Read Attribute Values or SMART Save Attribute Values
command.
