Digital: Ex Post

March 03, 2005

The PowerBook Sudden Motion Sensor

The PowerBook Sudden Motion Sensor: "In modern disk drives, the 'flying height' between the platter and the head is very small. This increases the possibility of a disturbed head colliding with the platter. Modern drives support 'parking' their heads in a safe position under various circumstances. In particular, heads are automatically parked when a system is powered off or sleeping. AMS adds the ability to park the heads in the event of an accidental drop, strong vibrations, or other abrupt movements. It works by detecting changes in the computer's orientation or the presence of accelerated movement. When the threshold for emergency action is reached, say, because of shock or 'free fall', an interrupt is generated. Processing of this interrupt by the AMS driver may result in a 'park' command being sent to the drive in a platform-dependent manner."


Post a Comment

<< Home