Datasheet

Data Sheet
BMA456
Page 37
BST-BMA456-DS000-01 | Version 1.1 | October 2017 Bosch Sensortec
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BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany.
Note: Specifications within this document are subject to change without notice.
Tilt on Wrist
How to perform the “Tilt on Wrist” gesture ideally:
1. Wrap the device on your wrist.
2. Lift the hand wearing the device up to a comfortable position and tilt it to minimum 12° to
gravity (see the image below for the valid position)
3. Wait for a second.
Valid position for Tilt on Wrist
The Tilt on Wrist Interrupt is detected with one accelerometer axis. Therefore, you should make sure
that the active axis is mapped to the portrait up direction of the device by using the axis remapping
functionality of BMA456. See the examples in the table below.
The table below shows the required remapping configurations for the Tilt on Wrist function based on
the sensor’s different orientations inside the device. More information about how to remap the axis
direction can be found in the general interrupt description in Chapter 4.6.
No.
Sensor direction
Mount
layer
Register configuration
Remarks
1
Top layer
map_x_axis = 0
map_x_axis_sign = 0
map_y_axis = 1
map_y_axis_sign = 0
map_z_axis = 2
map_z_axis_sign = 0
X = +x axis
Y = +y axis
Z = +z axis
Same as the
original mapping
g
Portrait up
Pin#1
Marking
g
Portrait up
Min 12°
Wrist rotation
Sensor