Datasheet

Z5K500 OEM Specifications
145
S.M.A.R.T. Return Status (Subcommand DAh)
This command is used to communicate the reliability status of the device to the host’s request. Upon
receipt of the S.M.A.R.T. Return Status subcommand the device asserts BSY, saves any updated
Attribute Values to the reserved sector and compares the updated Attribute Values to the Attribute
Thresholds.
If the device does not detect a Threshold Exceeded Condition, or detects a Threshold Exceeded
Condition but involving attributes are advisory, the device loads 4Fh into the LBA Mid register, C2h into
the LBA High register.
If the device detects a Threshold Exceeded Condition for prefailure attributes, the device loads F4h into
the LBA Mid register, 2Ch into the LBA High register. Advisory attributes never result in negative reliability
condition.
S.M.A.R.T. Enable/Disable Automatic Off-Line (Subcommand DBh)
This subcommand enables and disables the optional feature that cause the device to perform the set of
off-line data collection activities that automatically collect attribute data in an off-line mode and then save
this data to the device’s non-volatile memory. This subcommand may either cause the device to
automatically initiate or resume performance of its off-line data collection activities or cause the automatic
off-line data collection feature to be disabled. This subcommand also enables and disables the off-line
read scanning feature that cause the device to perform the entire read scanning with defect reallocation
as the part of the off-line data collection activities.
The Sector Count register shall be set to specify the feature to be enabled or disabled.
Sector Count Feature Description
00h Disable Automatic Off-line
01h Disable Off-line Read Scanning
F8h Enable Automatic Off-line
F9h Enable Off-line Read Scanning
A value of zero written by the host into the device’s Sector Count register before issuing this
subcommand shall cause the automatic off-line data collection feature to be disabled. Disabling this
feature does not preclude the device from saving attribute values to non-volatile memory during some
other normal operation such as during a power-on or power-off sequence or during an error recovery
sequence.
A value of one written by the host into the device’s Sector Count register before issuing this subcommand
shall cause the off-line read scanning feature to be disabled. The Device does not perform the off-line
read scanning at the off-line data collection activities which is initiated by the S.M.A.R.T. Execute Off-line
Immediate(Subcommand D4h) or automatically if the off-line read scanning feature is disabled.
A value of F8h written by the host into the device’s Sector Count register before issuing this subcommand
shall cause the automatic Off-line data collection feature to be enabled.
A value of F9 written by the host into the device’s Sector Count register before issuing this subcommand
shall cause the off-line read scanning feature to be enabled. The Device perform the off-line read
scanning at the off-line data collection activities which is initiated by the S.M.A.R.T. Execute Off-line
Immediate(Subcommand D4h) even if the automatic off-line feature is disabled.
Any other non-zero value written by the host into this register before issuing this subcommand is vender
specific and will not change the current Automatic Off-Line Data Collection and Off-line Read Scanning
status, but device may respond with the error code specified in “Table 125 S.M.A.R.T. Error Codes” on
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