IBM HDAPS Someone interested?

IBM HDAPS Someone interested?

[Alejandro Bonilla]

Hi,

	As I have asked before, I will do it again. Sorry if this is not the right
place.

I'm looking for someone, a hope, anything from anyone that have an IBM T40,
T41, T42 or whoever has the Embedded "Airbag" solution in their Linux
Laptops.

The Hard Drive Active Protection System, which is in the IBM laptops (and
maybe some others) uses an Analog ADXL320 (or ADXL202) with the
accelerometer for XY to monitor the movement in the laptops.

We have the Datasheet, Application notes and free "Tech support" from Analog
Devices. Now, we need some developers interested in getting this to work. We
just need someone to start something or to take a couple of minutes to see
if this is doable, and if a linux driver came be made to make it work.

(There is also a Fingerprint reader that I would like to get working, but
that is somehow screwed up by security layers) :)

PLEASE, if you have a couple of minutes, or if you are interested in getting
this working, Please let me/us know.

http://www.analog.com/en/prod/0,2877,ADXL320,00.html

http://www.analog.com/en/prodRes/0,2889,ADXL202%255F871,00.html


Thanks for the time.

.Alejandro

Re: IBM HDAPS Someone interested?

[Vojtech Pavlik]

On Mon, Jun 20, 2005 at 09:18:08AM -0600, Alejandro Bonilla wrote:
> Hi,
> 
> 	As I have asked before, I will do it again. Sorry if this is not the right
> place.
> 
> I'm looking for someone, a hope, anything from anyone that have an IBM T40,
> T41, T42 or whoever has the Embedded "Airbag" solution in their Linux
> Laptops.
> 
> The Hard Drive Active Protection System, which is in the IBM laptops (and
> maybe some others) uses an Analog ADXL320 (or ADXL202) with the
> accelerometer for XY to monitor the movement in the laptops.
> 
> We have the Datasheet, Application notes and free "Tech support" from Analog
> Devices. Now, we need some developers interested in getting this to work. We
> just need someone to start something or to take a couple of minutes to see
> if this is doable, and if a linux driver came be made to make it work.
> 
> (There is also a Fingerprint reader that I would like to get working, but
> that is somehow screwed up by security layers) :)
> 
> PLEASE, if you have a couple of minutes, or if you are interested in getting
> this working, Please let me/us know.
> 
> http://www.analog.com/en/prod/0,2877,ADXL320,00.html
> 
> http://www.analog.com/en/prodRes/0,2889,ADXL202%255F871,00.html

I already have the documentation for the chips for my robotics projects,
I even have the chips. I'll have an Airbag-equipped IBM notebook soon,
hopefully, too.

However, this is not enough at all to write the driver. The
accelerometer is a trivial analog component (ok, not so trivial, but
still just analog), and the main question is how it is connected to the
PC.

Until IBM says something about that, or somebody reverse engineers their
BIOS/Windows drivers/whatever, a driver can't be written.

-- 
Vojtech Pavlik
SuSE Labs, SuSE CR

RE: IBM HDAPS Someone interested?

[Alejandro Bonilla]

> > I'm looking for someone, a hope, anything from anyone that
> have an IBM T40,
> > T41, T42 or whoever has the Embedded "Airbag" solution in
> their Linux
> > Laptops.
> >
> > The Hard Drive Active Protection System, which is in the
> IBM laptops (and
> > maybe some others) uses an Analog ADXL320 (or ADXL202) with the
> > accelerometer for XY to monitor the movement in the laptops.
>
> I already have the documentation for the chips for my
> robotics projects,
> I even have the chips. I'll have an Airbag-equipped IBM notebook soon,
> hopefully, too.
>
> However, this is not enough at all to write the driver. The
> accelerometer is a trivial analog component (ok, not so trivial, but
> still just analog), and the main question is how it is
> connected to the
> PC.
>
> Until IBM says something about that, or somebody reverse
> engineers their
> BIOS/Windows drivers/whatever, a driver can't be written.
>
> --
> Vojtech Pavlik
> SuSE Labs, SuSE CR

I was told, that the only thing that was needed was an ADD card. ( Analog to
Digital?)

If you are interested, I can call you and then conference Analog Devices,
and they will tell you what is needed, I bet IBM did whatever Analog Devices
told them to do. And they might even tell us what to do if they talk with
someone that knows (I was bumbling, while he was talking about all the IO
and G rates)

I don't think they have anything in the BIOS related to the HDAPS, else they
would have put something in it. (You can't even disable the chip in the
BIOS) I just think is the accelerometer, there, by itself with an extra card
they added.

.Alejandro

Re: IBM HDAPS Someone interested?

[Vojtech Pavlik]

On Mon, Jun 20, 2005 at 10:16:09AM -0600, Alejandro Bonilla wrote:

> I was told, that the only thing that was needed was an ADD card. ( Analog to
> Digital?)

Indeed, but there is a zillion of different approaches to an A/D.
I'm quite sure IBM have rolled their own directly on the mainboard.

The main question is on which bus and which address it lives and what is
the programming interface. It's not something Analog Devices would know.

It can be on some monitoring chip living on the SMBus (most likely) or
coupled directly to the ACPI bridge on PCI, or anywhere else in the
system.

> If you are interested, I can call you and then conference Analog Devices,
> and they will tell you what is needed, I bet IBM did whatever Analog Devices
> told them to do. And they might even tell us what to do if they talk with
> someone that knows (I was bumbling, while he was talking about all the IO
> and G rates)

Well, I will not be interested until I'm convinced they'll be able to
tell me something I don't know already.

> I don't think they have anything in the BIOS related to the HDAPS, else they
> would have put something in it. (You can't even disable the chip in the
> BIOS) I just think is the accelerometer, there, by itself with an extra card
> they added.
 
Well, some piece of software needs to park the HDD when the notebook is
falling, and that piece of software should better be running since the
notebook is powered on. Hence my suspicion it's in the BIOS. It doesn't
have to be visible to the user, at all.

-- 
Vojtech Pavlik
SuSE Labs, SuSE CR

RE: IBM HDAPS Someone interested?

[Alejandro Bonilla]

> On Mon, Jun 20, 2005 at 10:16:09AM -0600, Alejandro Bonilla wrote:
>
> > I was told, that the only thing that was needed was an ADD
> card. ( Analog to
> > Digital?)
>
> Indeed, but there is a zillion of different approaches to an A/D.
> I'm quite sure IBM have rolled their own directly on the mainboard.
>
> The main question is on which bus and which address it lives
> and what is
> the programming interface. It's not something Analog Devices
> would know.
>
> It can be on some monitoring chip living on the SMBus (most likely) or
> coupled directly to the ACPI bridge on PCI, or anywhere else in the
> system.
>
> > If you are interested, I can call you and then conference
> Analog Devices,
> > and they will tell you what is needed, I bet IBM did
> whatever Analog Devices
> > told them to do. And they might even tell us what to do if
> they talk with
> > someone that knows (I was bumbling, while he was talking
> about all the IO
> > and G rates)
>
> Well, I will not be interested until I'm convinced they'll be able to
> tell me something I don't know already.

I bet they will. They don't document it all, and I'm pretty sure that if you
ask the right question, then they will tell you what you are looking for.
After all, they should be our first step before trying anything.

I it obvious to me that they have at least tried once, to play with the IBM
mechanism.

They could have an aswer for us right now and tell us things that could make
things really easy.

After all, you won't pay for the phone call. ;-)

.Alejandro

>
> > I don't think they have anything in the BIOS related to the
> HDAPS, else they
> > would have put something in it. (You can't even disable the
> chip in the
> > BIOS) I just think is the accelerometer, there, by itself
> with an extra card
> > they added.
>
> Well, some piece of software needs to park the HDD when the
> notebook is
> falling, and that piece of software should better be running since the
> notebook is powered on. Hence my suspicion it's in the BIOS.
> It doesn't
> have to be visible to the user, at all.
>
> --
> Vojtech Pavlik
> SuSE Labs, SuSE CR

Re: IBM HDAPS Someone interested?

[Pavel Machek]

Hi!

> > I don't think they have anything in the BIOS related to the HDAPS, else they
> > would have put something in it. (You can't even disable the chip in the
> > BIOS) I just think is the accelerometer, there, by itself with an extra card
> > they added.
>  
> Well, some piece of software needs to park the HDD when the notebook is
> falling, and that piece of software should better be running since the
> notebook is powered on. Hence my suspicion it's in the BIOS. It doesn't
> have to be visible to the user, at all.

Actually yes, it needs to be visible to the user and no, it probably should not run during boot.
If user is in plane/train, accellerometers will basically detect problems all the time;
still you want to use the computer.
(And you still want the machine to boot => default == fall detection off).

IIRC there's windows program to control it.

-- 
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Re: [ltp] Re: IBM HDAPS Someone interested?

[Lenz Grimmer]

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Hash: SHA1

Hi,

let me add my 2 cents here, as I have been toying around with this idea,
too..

Vojtech Pavlik wrote:

> Indeed, but there is a zillion of different approaches to an A/D. I'm
> quite sure IBM have rolled their own directly on the mainboard.
> 
> The main question is on which bus and which address it lives and what
> is the programming interface. It's not something Analog Devices would
> know.
> 
> It can be on some monitoring chip living on the SMBus (most likely)
> or coupled directly to the ACPI bridge on PCI, or anywhere else in
> the system.

I tried monitoring the output of the embedded controller register dump
that the "ibm-acpi" kernel module provides, using the following command
and then moving the Laptop (Thinkpad T42) to trigger changes:

  watch -n1 cat /proc/acpi/ibm/ecdump

Alas, there wasn't really a pattern that convinced me that the chip
actually is monitored via this controller. But of course it may not harm
if somebody else double checks this.

> Well, some piece of software needs to park the HDD when the notebook
> is falling, and that piece of software should better be running since
> the notebook is powered on. Hence my suspicion it's in the BIOS. It
> doesn't have to be visible to the user, at all.

On Windows, you need to run a separate tray application that enables the
protection. So it seems like it's implemented in "userspace". It may be
worth debugging what this Window applet actually does...

Bye,
	LenZ
- --
- ------------------------------------------------------------------
 Lenz Grimmer <lenz@grimmer.com>                             -o)
 [ICQ: 160767607 | Jabber: LenZGr@jabber.org]                /\\
 http://www.lenzg.org/                                       V_V
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RE: [ltp] Re: IBM HDAPS Someone interested?

[Alejandro Bonilla]

> I tried monitoring the output of the embedded controller register dump
> that the "ibm-acpi" kernel module provides, using the
> following command
> and then moving the Laptop (Thinkpad T42) to trigger changes:
>
>   watch -n1 cat /proc/acpi/ibm/ecdump
>
> Alas, there wasn't really a pattern that convinced me that the chip
> actually is monitored via this controller. But of course it
> may not harm
> if somebody else double checks this.
>
> > Well, some piece of software needs to park the HDD when the notebook
> > is falling, and that piece of software should better be
> running since
> > the notebook is powered on. Hence my suspicion it's in the BIOS. It
> > doesn't have to be visible to the user, at all.
>
> On Windows, you need to run a separate tray application that
> enables the
> protection. So it seems like it's implemented in "userspace".
> It may be
> worth debugging what this Window applet actually does...
>
> Bye,
> 	LenZ

Lenz,

	I will try this at home in about 4 hours and then let you know of the
output. This is really the first command that I can see that might give us
any/non information.

.Alejandro

Re: [ltp] Re: IBM HDAPS Someone interested?

[Pekka Enberg]

On 6/20/05, Lenz Grimmer <lenz@grimmer.com> wrote:
> On Windows, you need to run a separate tray application that enables the
> protection. So it seems like it's implemented in "userspace". It may be
> worth debugging what this Window applet actually does...

According to this [1], the mechanism can tell the difference between
harmful movements and repetitive motion which definitely suggests an
in driver (or userspace) statistics model based prediction.

P.S. I have a ThinkPad 41p or 42p at work. I am willing to help out if
it has the said device and we can get enough info on how to program
it.

                        Pekka

  1. http://www.anandtech.com/printarticle.aspx?i=1893

Re: [ltp] Re: IBM HDAPS Someone interested?

[Andrew Haninger]

On 6/20/05, Pekka Enberg <penberg@gmail.com> wrote:
> P.S. I have a ThinkPad 41p or 42p at work. I am willing to help out if
> it has the said device and we can get enough info on how to program
> it.
FWIW, I have a Thinkpad t42 with APS. It's still running Windows XP so
I'm not sure how much help I can be here. I will keep an eye on this
thread in the case that I can be of any assistance later.

-Andy

Re: IBM HDAPS Someone interested?

[Yani Ioannou]

> Actually yes, it needs to be visible to the user and no, it probably should not run during boot.
> If user is in plane/train, accellerometers will basically detect problems all the time;
> still you want to use the computer.

It does though :-) see my post.

Re: IBM HDAPS Someone interested?

[Vojtech Pavlik]

On Mon, Jun 20, 2005 at 06:57:04PM +0200, Pavel Machek wrote:
> Hi!
> 
> > > I don't think they have anything in the BIOS related to the HDAPS, else they
> > > would have put something in it. (You can't even disable the chip in the
> > > BIOS) I just think is the accelerometer, there, by itself with an extra card
> > > they added.
> >  
> > Well, some piece of software needs to park the HDD when the notebook is
> > falling, and that piece of software should better be running since the
> > notebook is powered on. Hence my suspicion it's in the BIOS. It doesn't
> > have to be visible to the user, at all.
> 
> Actually yes, it needs to be visible to the user and no, it probably
> should not run during boot.  If user is in plane/train,
> accellerometers will basically detect problems all the time; still you
> want to use the computer.

It likely won't. What it does is that it detects a situation with no
gravity - free fall.

> (And you still want the machine to boot => default == fall detection off).

It will boot. It may boot slower if you're jumping from an airplane at
the time, but it'll just park the heads now and then, which, with
IBM/Hitachi drives doesn't take long.

> IIRC there's windows program to control it.
 
That's likely. What good would a feature be for marketing if it wasn't
visible to the user. ;)

-- 
Vojtech Pavlik
SuSE Labs, SuSE CR

Re: IBM HDAPS Someone interested?

[Pavel Machek]

Hi!

> > > > I don't think they have anything in the BIOS related to the HDAPS, else they
> > > > would have put something in it. (You can't even disable the chip in the
> > > > BIOS) I just think is the accelerometer, there, by itself with an extra card
> > > > they added.
> > >  
> > > Well, some piece of software needs to park the HDD when the notebook is
> > > falling, and that piece of software should better be running since the
> > > notebook is powered on. Hence my suspicion it's in the BIOS. It doesn't
> > > have to be visible to the user, at all.
> > 
> > Actually yes, it needs to be visible to the user and no, it probably
> > should not run during boot.  If user is in plane/train,
> > accellerometers will basically detect problems all the time; still you
> > want to use the computer.
> 
> It likely won't. What it does is that it detects a situation with no
> gravity - free fall.

IIRC it is more complicated than that. Free fall is too late, laptop
usually fall from 1meter. Thats not enough time to park the
heads. Fortunately, laptop usually tilts before it falls off the table
-- and they are measuring the tilt before the fall. That buys them
enough time to actually do anything with it.

Story says, that they once had version that worked from 2meters+. It
was kind of useless, because no laptop ever fell from that height and
those that did were destroyed anyway.

[ s = a t ^ 2.
  s = ~1m.
  a = 9.8m*s^-2.

  t = sqrt( s/a )
  t = 
ucalc> (1 m / (9.8 * (m * sec ^ (-2)))) ^ 0.5
OK:  0.319438  sec

...ouch, it should be way faster, 0.3sec is definitely enough to park
heads.]

								Pavel
-- 
teflon -- maybe it is a trademark, but it should not be.

Re: IBM HDAPS Someone interested?

[Adam Goode]

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On Mon, 2005-06-20 at 22:45 +0200, Vojtech Pavlik wrote:
> On Mon, Jun 20, 2005 at 06:57:04PM +0200, Pavel Machek wrote:
> > Hi!
> > 
> > > > I don't think they have anything in the BIOS related to the HDAPS, else they
> > > > would have put something in it. (You can't even disable the chip in the
> > > > BIOS) I just think is the accelerometer, there, by itself with an extra card
> > > > they added.
> > >  
> > > Well, some piece of software needs to park the HDD when the notebook is
> > > falling, and that piece of software should better be running since the
> > > notebook is powered on. Hence my suspicion it's in the BIOS. It doesn't
> > > have to be visible to the user, at all.
> > 
> > Actually yes, it needs to be visible to the user and no, it probably
> > should not run during boot.  If user is in plane/train,
> > accellerometers will basically detect problems all the time; still you
> > want to use the computer.
> 
> It likely won't. What it does is that it detects a situation with no
> gravity - free fall.
> 
> > (And you still want the machine to boot => default == fall detection off).
> 
> It will boot. It may boot slower if you're jumping from an airplane at
> the time, but it'll just park the heads now and then, which, with
> IBM/Hitachi drives doesn't take long.
> 
> > IIRC there's windows program to control it.
>  
> That's likely. What good would a feature be for marketing if it wasn't
> visible to the user. ;)
> 


This paper tells about the "heuristic learning algorithm" used to park
the drives:

http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-53432

It seems that by IBM's calculations, desk-to-floor distance is
insufficient time to detect freefall and park the heads. So they
actually park the heads when it detects "starting to slide off table"...

Freefall detection: 300 ms
Head park time: 300-500 ms
  (from page 2 of document)

Still doesn't seem too bad to figure out how to code though, at least
once we can figure out how to get the data stream!

P.S. The main control system runs as a Windows kernel driver. Not as
safe as full hardware, but probably better than userspace. :)


Thanks,

Adam


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Re: IBM HDAPS Someone interested?

[Pavel Machek]

Hi!

Apple connects their accelerometer over i2c, see:

http://www.kernelthread.com/software/ams/

For some reverse engineering attempts, see:

http://www.paul.sladen.org/thinkpad-r31/accelerometer.html

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

http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-53167

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

http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-53432

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. 

								Pavel
-- 
teflon -- maybe it is a trademark, but it should not be.

Re: IBM HDAPS Someone interested?

[Alejandro Bonilla]

Pavel Machek wrote:

>Hi!
>
>Apple connects their accelerometer over i2c, see:
>
>http://www.kernelthread.com/software/ams/
>
>For some reverse engineering attempts, see:
>
>http://www.paul.sladen.org/thinkpad-r31/accelerometer.html
>
>According to IBM, it is *not* enabled during system bootup:
>
>http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-53167
>
>According to another text, BIOS know how to test accelerometer in some
>kind of self test. Aha, here's the most interesting text:
>
>http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-53432
>
>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. 
>
>								Pavel
>  
>
Pavel,

    Thanks for all this information and to everyone providing data. This 
is really want we want. But We need to know how to talk to the chip 
before getting any on these math results to work.

Try what Lenz said: watch -n1 cat /proc/acpi/ibm/ecdump

.Alejandro

Re: IBM HDAPS Someone interested?

[Alejandro Bonilla]

Alejandro Bonilla wrote:

> Pavel Machek wrote:
>
>> Hi!
>>
>> Apple connects their accelerometer over i2c, see:
>>
>> http://www.kernelthread.com/software/ams/
>>
>> For some reverse engineering attempts, see:
>>
>> http://www.paul.sladen.org/thinkpad-r31/accelerometer.html
>>
>> According to IBM, it is *not* enabled during system bootup:
>>
>> http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-53167 
>>
>>
>> According to another text, BIOS know how to test accelerometer in some
>> kind of self test. Aha, here's the most interesting text:
>>
>> http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-53432 
>>
>>
>> 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.
>>                                 Pavel
>>  
>>
Boris,

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

.Alejandro

Re: IBM HDAPS Someone interested?

[Lee Revell]

On Mon, 2005-06-20 at 17:30 -0400, Adam Goode wrote:
> Freefall detection: 300 ms
> Head park time: 300-500 ms
>   (from page 2 of document)
> 
> Still doesn't seem too bad to figure out how to code though, at least
> once we can figure out how to get the data stream!
> 
> P.S. The main control system runs as a Windows kernel driver. Not as
> safe as full hardware, but probably better than userspace. :)
> 

Ugh, if userspace can't meet a 300ms RT constraint, that's a pretty
shitty OS you have there.

This should certainly be done in userspace on Linux.

Lee

Re: IBM HDAPS Someone interested?

[Vojtech Pavlik]

On Tue, Jun 21, 2005 at 11:37:38AM -0400, Lee Revell wrote:

> On Mon, 2005-06-20 at 17:30 -0400, Adam Goode wrote:
> > Freefall detection: 300 ms
> > Head park time: 300-500 ms
> >   (from page 2 of document)
> > 
> > Still doesn't seem too bad to figure out how to code though, at least
> > once we can figure out how to get the data stream!
> > 
> > P.S. The main control system runs as a Windows kernel driver. Not as
> > safe as full hardware, but probably better than userspace. :)
> > 
> 
> Ugh, if userspace can't meet a 300ms RT constraint, that's a pretty
> shitty OS you have there.

It's not that you do one measurement in the 300ms. You need to do at least
100, and some computations, too.

> This should certainly be done in userspace on Linux.

So it's a 3ms RT constraint, which is not as easy.

-- 
Vojtech Pavlik
SuSE Labs, SuSE CR

Re: IBM HDAPS Someone interested?

[Lee Revell]

On Tue, 2005-06-21 at 18:45 +0200, Vojtech Pavlik wrote:
> On Tue, Jun 21, 2005 at 11:37:38AM -0400, Lee Revell wrote:
> > Ugh, if userspace can't meet a 300ms RT constraint, that's a pretty
> > shitty OS you have there.
> 
> It's not that you do one measurement in the 300ms. You need to do at least
> 100, and some computations, too.
> 
> > This should certainly be done in userspace on Linux.
> 
> So it's a 3ms RT constraint, which is not as easy.
> 

Heh, we do it all the time with JACK.

But, I think I was wrong anyway, you'll have to do it in the kernel
because you would need PREEMPT to meet that with any degree of
certainty.

Lee

Re: IBM HDAPS Someone interested?

[Valdis.Kletnieks]

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On Tue, 21 Jun 2005 11:37:38 EDT, Lee Revell said:
> On Mon, 2005-06-20 at 17:30 -0400, Adam Goode wrote:
> > Freefall detection: 300 ms
> > Head park time: 300-500 ms

> Ugh, if userspace can't meet a 300ms RT constraint, that's a pretty
> shitty OS you have there.

Actually, it's a lot tighter than that.  You need to *issue* the "park head"
command 300-500ms before it hits the ground, and you have 300ms of free fall.

So you may have needed to detect the free fall and issue the command 200ms
before the free fall commences.

That's a *real* hard RT constraint to keep. ;)

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Re: IBM HDAPS Someone interested?

[Sander]

Valdis.Kletnieks@vt.edu wrote (ao):
> On Tue, 21 Jun 2005 11:37:38 EDT, Lee Revell said:
> > On Mon, 2005-06-20 at 17:30 -0400, Adam Goode wrote:
> > > Freefall detection: 300 ms
> > > Head park time: 300-500 ms
> 
> > Ugh, if userspace can't meet a 300ms RT constraint, that's a pretty
> > shitty OS you have there.
> 
> Actually, it's a lot tighter than that. You need to *issue* the "park
> head" command 300-500ms before it hits the ground, and you have 300ms
> of free fall.
> 
> So you may have needed to detect the free fall and issue the command
> 200ms before the free fall commences.
> 
> That's a *real* hard RT constraint to keep. ;)

FWIW. I have a X40 and am still running windows. The harddisk protection
software has an icon in the windows bar near the clock which shows if
the disk is 'not parked', 'parked due to movement of the notebook', or
'not parked, but a steady stream of possible harmless shocks is
noticed'.

The software reacts very quick and is very sensitive. The slightest
movement of the notebook makes the disk park its heads instantly (very,
very quick) for a moment with a fairly loud click. Even if you just
slide the notebook a centimeter over the table or tilt it a little. The
software also has a realtime '3D' image of the notebook which show the
tilting of the notebook. Pretty neat.

I once tripped over the network cable and had the notebook fly through
the air and eventually hit the floor. The harddisk was still fine (as
was the rest of the notebook which impressed me because the lid was in a
180 degree angle with the keyboard after it hit the floor).

Please let me know if I can be of any help running windows or linux.

        With kind regards, Sander

RE: IBM HDAPS Someone interested?

[Alejandro Bonilla]

> little. The
> software also has a realtime '3D' image of the notebook which show the
> tilting of the notebook. Pretty neat.
>
> I once tripped over the network cable and had the notebook fly through
> the air and eventually hit the floor. The harddisk was still fine (as
> was the rest of the notebook which impressed me because the
> lid was in a
> 180 degree angle with the keyboard after it hit the floor).
>
> Please let me know if I can be of any help running windows or linux.
>
>         With kind regards, Sander

Sander,

	This is exactly what we want here. Once we have information on how to
access the device, we will be able to create all these nice features, that
for example, will help people that had your same problem. Imagine that just
because someone tripped over the cable, you will loose your HD, data,
backup, Music and so on. And the worst thing, your laptop has the feature,
but you can't use it. I was also looking into making the 3D show, but,
nothing can't be done until someone figures out, or IBM releases some specs.

	Thanks for adding yourself into the thread.

.Alejandro