11.9 Protected Area Function
Protected Area Function is to provide the 'protected area' which cannot be accessed via conventional
methods. This 'protected area' is used to contain critical system data such as BIOS or system
management information. The contents of the entire system main memory may also be dumped into the
'protected area' to resume after a system power off.
The LBA/CYL changed by the following commands affects the Identify Device Information.
Two commands are defined for this function.
Read Native Max ADDRESS ('F8'h)
Set Max ADDRESS ('F9'h)
Four security extension commands are implemented as subfunctions of the Set Max ADDRESS.
Set Max UNLOCK
Set Max FREEZE LOCK
Set Max LOCK
Set Max SET PASSWORD
11.9.1 Example for operation (In LBA Mode)
Assumptions :
For easier understanding the following example uses actual values for LBA, size, etc. Since it is an
example, these values will differ.
Device characteristics
0FC000h to 0FFFFFhLBA range for protected area
1,032,192 (0FC000h)Customer usable sector count
528,482,304 byte (528MB)Customer usable device size
16,384 (004000h)Required blocks for protected area
8,388,608 byteRequired size for protected area
1,048,575 (0FFFFFh)Max LBA (native)
536,870,912 byte (536MB)Capacity (native)
1. Shipping HDDs from the HDD manufacturer
When the HDD is shipped from the manufacturer, the device has been tested to have a capacity of
536 MB, flagging the media defects not visible by the system.
2. Preparing HDDs at system manufacturer
Special utility software is required to define the size of the protected area and store the data in it. The
sequence is:
Issue Read Native Max ADDRESS command to get the real device max. of LBA/CYL. Returned value
shows that native device Max LBA is 0FFFFFh regardless of the current setting.
Make entire device accessible, including the protected area, by setting the device Max LBA as
0FFFFFh via Set Max ADDRESS command. The option could be either nonvolatile or volatile.
Test the sectors for protected area (LBA > = 0FC000h) if required.
Write information data such as BIOS code within the protected area.
Travelstar 48GH, 30GN & 15GN hard disk drive specifications
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