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7K200 SATA OEM Specification 

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14.39.1.9 S.M.A.R.T. Disable Operations (Subcommand D9h)   

This subcommand disables all S.M.A.R.T.capabilities within the device including the device’s 

attribute autosave feature. After receipt of this subcommand the device disables all S.M.A.R.T. 
operations. Non self-preserved Attribute Values will no longer be monitored. The state of 

S.M.A.R.T. (either enabled or disabled) is preserved by the device across power cycles. Note that 

this subcommand does not preclude the device’s power mode attribute autosaving.   

Upon receipt of the S.M.A.R.T. Disable Operations subcommand from the host, the device disables 

S.M.A.R.T. capabilities and functions.   
After receipt of the device of the S.M.A.R.T. Disable Operations subcommand from the host, all other 
S.M.A.R.T. subcommands—with the exception of S.M.A.R.T. Enable Operations—are disabled, and 

invalid and will be aborted by the device (including the S.M.A.R.T. Disable Operations subcommand), 

returning the error code as specified in “Table 123 S.M.A.R.T. Error Codes” on Page 155.   

Any Attribute Values accumulated and saved to volatile memory prior to receipt of the S.M.A.R.T. 

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 S.M.A.R.T. Read 
Attribute Values or S.M.A.R.T. Save Attribute Values command.   

14.39.1.10  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.   

14.39.1.11  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