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Date: Tue, 23 Aug 2005 20:08:16 +0800
From: Erich Dollansky <oceanare@pacific.net.sg>
Organization: oceanare pte ltd
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To: Gary Jennejohn <fbsd@jennejohn.org>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: IBM Active Protection System Approach
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Hi,

Gary Jennejohn wrote:
> Borja Marcos writes:
> 
>>>Søren Schmidt writes:

> It seems to me that the worst-case scenario, dropping the laptop,
> would result in extremely high G-loading in microsecomds rather than
> milliseconds. Not much can be done to save the disk in such a short
> time.
> 
The sensor will notice already the start of the move. The notebook will 
then normally be accalerated with 1G as it simply goes into a free fall.

If the heads are then moved away from the disks and the notebook hits 
some ms later ground, it does not matter any more if this event takes 
micro- or milliseconds as the heads are already out of the danger zone.

Erich