Re: IBM HDAPS Someone interested?

From: Alejandro Bonilla
Date: Mon Jun 20 2005 - 19:54:55 EST

Alejandro Bonilla wrote:

Pavel Machek wrote:


Apple connects their accelerometer over i2c, see:

For some reverse engineering attempts, see:

According to IBM, it is *not* enabled during system bootup:

According to another text, BIOS know how to test accelerometer in some
kind of self test. Aha, here's the most interesting text:

According to this text:

typical free-fall takes 300msec, but head unloading takes
300-500msec. [So I had my computation right ;-)] ... "therefore, it is
too late to start head unloading after detecting free fall"...

They really try to detect conditions just before free fall... and it
does not sound that difficult.

Another clever trick is that if user is still using the mouse, machine
is probably not in free fall ;-). In pdf, they also mention few
.sys files. They should probably be disassembled to learn how the
interface works (hint hint), actually exported symbol names should be
quite helpfull in determining what function is the interesting one.


Do you know anything about the HD APS? Is it linked to the embedded controller?

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