This standard describes a BIOS firmware layer that may be used to both place and
execute system diagnostics on a protected area of the system hard disk. The purpose
of these diagnostics is to accurately determine for both the user and a technical support
engineer that the hard drive is functioning correctly. These diagnostics are placed in a
protected area of the disk drive because they are less vulnerable to attack from viruses,
system software corruption, and the user. The firmware layer described herein may
also be used to run DOS-based rescue utilities once the drive has been shown to be
working by the diagnostics described above. The net effect of these capabilities is that
a system may ship with embedded diagnostic and rescue capabilities, and that these
capabilities are known to be reliable by the system manufacturer and may not be easily
corrupted by the user.
The BIOS firmware described in this standard may be implemented for any disk drive
that conforms to ANSI NCITS 317-1998 (ATA/ATAPI-4) and implements the SET MAX
command. The SET MAX command as it is defined in ANSI NCITS 317-1998 provides
a great deal of security for hiding data on the disk drive. If the system is unable to boot
the primary operating system, the area protected by the SET MAX ADDRESS
command remains bootable.
All the fields described in this standard are designed to last at least 20 years, given a
doubling in capacity each year.
This standard describes a method for the BIOS to do the following:
Find the start of the reserved area boot code and issue SET MAX ADDRESS command
Emulate the reserved area boot code as a bootable floppy
This standard employs a method that is flexible enough to allow the reserved area boot
code to be seen as the primary floppy drive.
| ANSI : | ANSI Approved |
| Number of Pages : | 31 |
| Published : | 03/13/2001 |
