Fun with the iPhone accelerometer

Posted by on under light sensors, lengthy bout, iphe, straw poll, accelerometer, arm assembly, safari browser, input methods, pxl, iphone, input device, smackbook, reverse engineering, raw data, fun stuff, repository, source code, hack, balls, blog |

Note (9/12): there is an application in the iBrickr PXL repository called 'Balls' which links to this page. I have nothing to do with that app; it was created by Grudgnor over at the MacRumors forum.

Those who have followed this blog will know that I like to like to play with unusual input methods (see my earlier posts on , ambient light sensors, and the SmackBook).

As it turns out, the iPhone has a built-in LIS302DL, a tiny 3-axis accelerometer. While some have attempted to use it from within the Safari browser (the Tilt game detects changes to the width of the browser page; it is basically used as a 1-bit input device), its potential is still somewhat untapped.

After a rather lengthy bout of reverse-engineering (I had barely touched ARM assembly before this), I finally figured out how to access the raw data from the accelerometer itself, as can be seen in the video above. Source code will be posted as soon as possible is posted here. (update: yes, it is possible to access the accelerometer directly through UIKit without this hack -- however, you'll be locked to the default sample rate, which is too slow for some of the fun stuff)

Straw poll: What would you like to see on the iPhone?

Tagi: light sensors, lengthy bout, iphe, straw poll, accelerometer, arm assembly, safari browser, input methods, pxl, iphone, input device, smackbook, reverse engineering, raw data, fun stuff, repository, source code, hack, balls, blog