Hitachi IC25N010ATCS04, Технические характеристики

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11.10 Protected Area Function
Protected Area Function is to provide a "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 sub functions of the Set Max ADDRESS:
Set Max SET PASSWORD
Set Max LOCK
Set Max FREEZE LOCK
Set Max UNLOCK
11.10.1 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 0FFFFFh LBA range for protected area
1,032,192 (0FC000h) Customer usable sector count
528,482,304 bytes (528MB) Customer usable device size
16,384 (004000h) Required blocks for protected area
8,388,608 bytes Required size for protected area
1,048,575 (0FFFFFh) Max LBA (native)
536,870,912 bytes (536MB) Capacity (native)
1. Shipping drives from the drive manufacturer
When the drive 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 drives at system manufacturer
Special utility software is required to define the size of the protected area and to 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 the 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.
Hitachi Travelstar 60GH & 40GN hard disk drive specifications
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