The Second NEO Freerunner Sensor, in contrast to the first sensor is turned 45 degrees around the Z axis. See the attached image to get a clue about its orientation.
The information from both of the accelerometers is exported through two different input event based file mappings. These device nodes can be found at /dev/input/event2 and /dev/input/event3.
The QAccelerometer Class emit an Event called accelerate(qreal x, qreal y, qreal z) that gives you X, Y, Z axis values.
Each acceleration event relays the current acceleration readings along the three axes of the device. Therefore, a value of 1.0 represents a load of about +1g along a given axis while a value of -1.0 represents -1g.
You can find More information about OpenMoko Accelerometer here "Accelerometer Data Retrieval" and "Accelerometer Technical Fundamentals".
Keep in Mind this Simple Table of X, Y, Z axis and Phone State:
( 0, 0, 1) = Front
( 0, 0, -1) = Back
( 1, 0, 0) = Vertical (Short Side), Right
(-1, 0, 0) = Vertical (Short Side), Left
( 0, -1, 0) = Vertical (Long Side), Front
( 0, 1, 0) = Vertical (Long Side), Back
The Source Code is Available Here: NEO QAccelerometer Test Source Code.
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