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-   -   N900 sensitive to magnets. Magnetic case latches can wake device. (https://talk.maemo.org/showthread.php?t=36194)

mullf 2010-02-10 04:02

Re: N900 sensitivie to magnets. Magnetic case latches can wake device.
 
I've always known that magnetic fields are the way SATAN interacts with the physical world.

mcdull 2010-02-10 04:02

Re: N900 sensitivie to magnets. Magnetic case latches can wake device.
 
I think it's common to phone, for whatever reason, it's not only on N900.
I tried a magnet on the back of a Motorola Droid, it woke that up as well

woody14619 2010-02-10 04:51

Re: Nokia N900 problem with magnatic fields
 
Quote:

Originally Posted by frethop (Post 461185)
And you can;t find a case without a magnet, it seems.

I have one from the Verizon store that's perfectly fine, uses velcro. I work with sensitive systems that have lots of storage on magnetic media, so I disliked the idea of having a case with a magnetic chunk in it. Guess I was lucky to have avoided it.

It looks pretty simple to fix though. Just add an option to disable the keyboard slide from triggering a wake-up. In fact, while you're at it, add options to turn on/off the lock switch, power supplied, and front slider as well, since some people prefer to disable such things. (Just make sure they can't disable ALL of them at once. :D )

woody14619 2010-02-10 04:58

Re: Nokia N900 problem with magnatic fields
 
Quote:

Originally Posted by codeMonkey (Post 461704)
And for the back - the camera slider has a similar setup.

Not true. The camera lens cover slider is not a magnetic system, it's optical. Just pop the back off an you'll see the cover is blue, with a half-white/half-black bar. That bar lines up with an optical sensor that "reads" the light bounce back for the cover to determine if it's open or closed.

The rail switch for the left rail does seem to be close to it, so that may be throwing if you put the magnet near the camera. But the camera doesn't use a magnetic sensor to sense the lens cover. If it did, a magnet there would turn it on and start the camera software. I wonder how much a 3 hour video of the inside of your case would wear down the battery? :rolleyes:

egoshin 2010-02-10 19:45

Re: N900 sensitivie to magnets. Magnetic case latches can wake device.
 
Quote:

Originally Posted by supersniper3008 (Post 518776)
I had this problem before, and my solution is put the N900' s screen face to you body in the leather case. That can avoid your phone is waken up by magnetic clip :D

Sometime it doesn't work - I noted it in dark room.

Taomyn 2010-02-11 13:37

Re: magnetic closure on case activates device
 
Quote:

Originally Posted by Moli_T (Post 510317)
The desing flaw is using a magnetic closure on case. Magnetism causes interferences to electronics, discharges batteries, etc..

A small magnetic exposure for a short time is harmless, but can cause serious damage like data loss if the exposure time increases.

Sorry for bad English.

Unlikely - RIM have been using this idea for Blackberry's for years - all their cases all have magnets so the handset can detect when it has been "holstered", as they call it, and switches the phone to standby-mode or can be set to auto-answer/open email when removed.

I've just got a PDAair case with magnetic clasp and then found this thread. However it took a few swipes of the phone near the magnet to get the screen to switch on - I think it's fairly weak. I doubt it's going to cause me any issues, but I'm simply going to get into the habit of placing the screen on the other side of the case when I insert it, so screen towards my body. That should sort it :D

aperles 2010-03-04 00:14

Re: N900 sensitivie to magnets. Magnetic case latches can wake device.
 
According to the service manual, the sensor detecting the movement of the keyboard is a magneto-resistive, but no details about the specific model.

I tried to find a kernel module (lsmod) which name corresponds to a magnetorresitive sensor without success.

Also I tried to find a high-resolution image of the internals of the N900, but no luck.

Someone could help giving more specific information about the sensor, or a high resolution image?

This could let us to find a provisional solution, may be commenting out some line of the initialization scripts of the kernel.

Regards,
Àngel

danramos 2010-03-04 00:38

Re: N900 sensitivie to magnets. Magnetic case latches can wake device.
 
Quote:

Originally Posted by mcdull (Post 518789)
I think it's common to phone, for whatever reason, it's not only on N900.
I tried a magnet on the back of a Motorola Droid, it woke that up as well

YYYYyyep! A great exploit, if you ever find one and it's locked. Just touch it to a magnet and it'll go into multimedia base mode or car mode and VOILA! You have access to the phone. Seems like a big flaw to me. I've got 2.0.1 but hopefully they will have fixed that in 2.1.

anti-dualism 2010-03-05 19:56

Re: magnetic closure on case activates device
 
Quote:

Originally Posted by Taomyn (Post 521135)
Unlikely - RIM have been using this idea for Blackberry's for years - all their cases all have magnets so the handset can detect when it has been "holstered", as they call it, and switches the phone to standby-mode or can be set to auto-answer/open email when removed.

I've just got a PDAair case with magnetic clasp and then found this thread. However it took a few swipes of the phone near the magnet to get the screen to switch on - I think it's fairly weak. I doubt it's going to cause me any issues, but I'm simply going to get into the habit of placing the screen on the other side of the case when I insert it, so screen towards my body. That should sort it :D

Does the screen turn on with the screen placed facing your body in the holster?

taril 2010-03-06 23:01

Re: N900 sensitivie to magnets. Magnetic case latches can wake device.
 
not only wakes up my n900, it starts music player widget or any shortcuts around it like bounce. funny. i do hope it wont autocall ever.


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