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Do modern SSD-based MacBook Pro's have an accelerometer / gyroscope / sudden motion sensor?

On my old 2007 MacBook Pro I used to see the Chrome logo shift and tilt on this HTML5 Rocks page, and I'd experimented myself hooking into the deviceorientation event.

However, neither of these demos work on a 2012 SSD-based MacBook Pro. Additionally pmset -g doesn't list sms (Sudden Motion Sensor):

silent:~ searle$ pmset -g
Active Profiles:
Battery Power       -1*
AC Power        -1
Currently in use:
 standbydelay         4200
 standby              1
 halfdim              1
 hibernatefile        /var/vm/sleepimage
 darkwakes            0
 gpuswitch            2
 disksleep            10
 sleep                0
 autopoweroffdelay    14400
 hibernatemode        3
 autopoweroff         1
 ttyskeepawake        1
 displaysleep         0
 acwake               0
 lidwake              1

This apple suport page for Sudden Motion Sensor claims all Intel-based Macs have a sudden motion sensor.

So the question is: does my mac have a sudden motion sensor / accelerometer / gyroscope? If so, why can't I see it in pmset -g output, and how can I make use of it?


Re-reading Apple's support page, I now see this:

Note: Computers with Solid State Drives (SSD) or Flash Storage do not use SMS as the drives have no moving parts.

The question still remains - even if it doesn't use an SMS, does the laptop have an accelerometer / gyroscope?

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Have you checked in System Information? I've got a MacBookPro8,2 which shows Sudden Motion Sensor: State: Enabled under Hardware. – fgb Apr 21 '13 at 7:50
Yes, I'e checked. I can't see anything like Sudden Motion Sensor or Accelerometer. Screenshot of MBPr Hardware – searlea Apr 21 '13 at 17:58

The sudden motion sensor is a triaxial accelerometer that Apple includes when computers are equipped with mechanical hard drives. There are a few comments at the Apple Support Communities [1, 2, 3] that suggest that the sensor is not present in newer laptops that only come with an SSD option, but is still present when there's an HDD option. Apple doesn't seem to list sms in their Tech Specs, but you might want to check the relevant specifications by entering your serial number.

Keep in mind that this sensor should cost around $1 in bulk (estimated from other Kionix accelerometers on Mouser) and, in their new breed of computers with no serviceable parts that come with an SSD, it would only make sense for them to get rid of it.

share|improve this answer
Agree it would make sense to get rid of it if there were no other use. However, it would be convenient to include one to help development of tilt-based games / sites / apps. – searlea Apr 22 '13 at 22:07
That's true, although I'd guess their response to that would be to direct you to the iPad/iPhone platforms. Can't they be used as a USB peripheral during development? – fgb Apr 24 '13 at 2:31

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