Host protected area  From Wikipedia, the free encyclopedia Jump
to: navigation, search  The host protected area (also referred
to as hidden protected area[1]) is an area of a hard drive that
is not normally visible to an operating system (OS).   HPA was
first introduced in the ATA-4 standard cxv (T13, 2001).[2]  How
it works[edit]  Creation of an HPA. The diagram shows how a host
protected area (HPA) is created. # IDENTIFY DEVICE returns the
true size of the hard drive. READ NATIVE MAX ADDRESS returns the
true size of the hard drive. # SET MAX ADDRESS reduces the
reported size of the hard drive. READ NATIVE MAX ADDRESS returns
the true size of the hard drive. An HPA has been created. #
IDENTIFY DEVICE returns the now fake size of the hard drive.
READ NATIVE MAX ADDRESS returns the true size of the hard drive,
the HPA is in existence.  The IDE controller has registers that
contain data that can be queried using ATA commands. The data
returned gives information about the drive attached to the
controller. There