IBM DTNA-22160 - Travelstar 2.1 GB Hard Drive, Технические характеристики

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DAh S M A R T Return Status
12.29.1.1 SMART Read Attribute Values (Subcommand D0h)
This subcommand returns the device's Attribute Values to the host. Upon receipt of the S M A R T Read
Attribute Values subcommand from the host, the device asserts BSY, saves any updated Attribute Values to
the Attribute Data sectors, asserts D R Q , clears BSY, asserts INTRQ, and then waits for the host to transfer
the 512 bytes of Attribute Value information from the device via the Data Register.
12.29.1.2 SMART Read Attribute Thresholds (Subcommand D1h)
This subcommand returns the device's Attribute Thresholds to the host. Upon receipt of the S M A R T Read
Attribute Thresholds subcommand from the host, the device asserts BSY, reads the Attribute Thresholds
from the Attribute Threshold sectors, asserts D R Q , clears BSY, asserts INTRQ, and then waits for the host
to transfer the 512 bytes of Attribute Thresholds information from the device via the Data Register.
12.29.1.3 SMART Enable/Disable Attribute Autosave (Subcommand D2h)
This subcommand enables and disables the attribute autosave feature of the device. The S M A R T
Enable/Disable Attribute Autosave subcommand allows the device to automatically save its updated Attri-
bute Values to the Attribute Data Sector at the timing of the first transition to LP idle mode after 30
minutes since the last saving of Attribute Values; this subcommand causes the autosave feature to be disa-
bled. 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 device's Sector Count Register before issuing the S M A R T
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 device's Sector Count Register before issuing the S M A R T
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 S M A R T Enable/Disable Attribute Autosave
subcommand will not change the current Autosave status but the device will respond with the error code
specified in Figure 90 on page 142.
The S M A R T Disable Operations subcommand disables the autosave feature along with the device's
S M A R T operations.
Upon the receipt of the subcommand from the host, the device asserts BSY, enables or disables the
Autosave feature, clears BSY and asserts INTRQ.
12.29.1.4 SMART Save Attribute Values (Subcommand D3h)
This subcommand causes the device to immediately save any updated Attribute Values to the device's Attri-
bute Data sector regardless of the state of the Attribute Autosave feature. Upon receipt of the S M A R T Save
Attribute Values subcommand from the host, the device asserts BSY, writes any updated Attribute Values to
the Attribute Data sector, clears BSY and asserts INTRQ.
Command Descriptions
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