IBM IC35L040AVVN07-0 - 40GB IDE Deskstar 120GXP 7200RPM UATA-100..., Specifications

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11.33.1 S.M.A.R.T. Subcommand
In order to select a subcommand the host must write the subcommand code to the Features Register of
the device before issuing the S.M.A.R.T. Function Set command. The subcommands and their respective
codes are listed below.
SMART Enable/Disable Automatic Off Line DBh
SMART Return Status DAh
SMART Disable Operations D9h
SMART Enable Operations D8h
SMART Write Log Sector D6h
SMART Read Log Sector D5h
SMART Execute Off-line Immediate D4h
SMART Save Attribute Values D3h
SMART Enable/disable Attribute Autosave D2h
SMART Read Attribute Thresholds D1h
SMART Read Attribute Values D0h
Subcommand Code
11.33.1.1 SMART Read Attribute Values (Subcommand D0h)
This subcommand returns the Attribute Values of the device to the host. Upon receipt of the SMART Read
Attribute Values subcommand from the host the device saves any updated Attribute Values to the
Attribute Data sectors and then transfers the 512 bytes of Attribute Value information to the host.
11.33.1.2 SMART Read Attribute Thresholds (Subcommand D1h)
This subcommand returns the Attribute Thresholds of the device to the host. Upon receipt of the SMART
Read Attribute Thresholds subcommand from the host, the device reads the Attribute Thresholds from the
Attribute Threshold sectors and then transfers the 512 bytes of Attribute Thresholds information to the
host.
11.33.1.3 SMART Enable/Disable Attribute Autosave (Subcommand D2h)
This subcommand enables and disables the Attribute Autosave feature of the device. The SMART
Enable/Disable Attribute Autosave subcommand either allows the device to automatically save its updated
Attribute Values to the Attribute Data Sector periodically or causes the Autosave feature to be disabled.
The state of the Attribute Autosave feature (either enabled or disabled) will be preserved by the device
across power cycle.
A value of 00h written by the host into the Sector Count Register of the device before issuing the SMART
Enable/Disable Attribute Autosave subcommand will cause this feature to be disabled. Disabling this
feature does not preclude the device from saving Attribute Values to the Attribute Data sectors during
some other normal operation such as during a power-up or power-down.
A value of F1h written by the host into the Sector Count Register of the device before issuing the SMART
Enable/Disable Attribute Autosave subcommand will cause this feature to be enabled. Any other non- zero
value written by the host into this register before issuing the SMART Enable/Disable Attribute Autosave
subcommand will not change the current Autosave status but the device will respond with the error code
specified in Figure 151 on page 177.
The SMART Disable Operations subcommand disables the Autosave feature along with the SMART
operations of the device.
Deskstar 120GXP hard disk drive specifications
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