Hitachi 7K400 Specifications - Page 224
S.M.A.R.T. Enable/Disable Automatic Off-line subcommand DBh
UPC - 000053412935
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12.46.1.9 S.M.A.R.T. Disable Operations (subcommand D9h) This subcommand disables all S.M.A.R.T. capabilities within the device including the attribute Autosave feature of the device. 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. Upon receipt of the S.M.A.R.T. Disable Operations subcommand from the host, the device asserts BSY, disables S.M.A.R.T. capabilities and functions, clears BSY, and asserts INTRQ. 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 166: "S.M.A.R.T. Error Codes" on page 220. 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 a S.M.A.R.T. Save Attribute Values command. 12.46.1.10 S.M.A.R.T. Return Status (subcommand DAh) This command is used to communicate the reliability status of the device upon the request of the host. Upon receipt of the SMART Return Status subcommand the device saves any updated Pre-failure type 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, the device loads 4Fh into the Cylinder Low register and C2h into the Cylinder High register. If the device detects a Threshold Exceeded Condition, the device loads F4h into the Cylinder Low register and 2Ch into the Cylinder High register. 12.46.1.11 S.M.A.R.T. Enable/Disable Automatic Off-line (subcommand DBh) This subcommand enables and disables the optional feature that causes the device to perform the set of off-line data collection activities that automatically collect attribute data in an off-line mode and then saves this data to the nonvolatile memory of the device. 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. A value of zero written by the host into the Sector Count register of the device before issuing this subcommand causes the feature to be disabled. Disabling this feature does not preclude the device from saving attribute values to nonvolatile 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 F8h written by the host into the Sector Count register of the device before issuing this subcommand causes this feature to be enabled. Any other nonzero value written by the host into this register before issuing this subcommand is vender specific and does not change the current Automatic Off-line Data Collection status, but the device may respond with the error code specified in Table 166: "S.M.A.R.T. Error Codes" on page 220. Deskstar 7K400 Hard Disk Drive Specification 210