CMA3000-D0X Datasheet, PDF (11/35 Pages) VTI technologies – 3-axis accelerometer

CMA3000-D0X Series
2.6 Interrupt function (INT-pin)
2.6.1 Usage
Depending on the CMA3000 operational configuration, the INT-pin can give an interrupt in following
cases:
1. Normal measurement mode: INT-pin gives interrupt when new data is available
2. Free fall detection mode: INT-pin gives an interrupt to signal that free fall is detected
3. Motion detection mode: INT-pin gives an interrupt to signal that motion is detected
Interrupt polarity (active high/low) can be configured with CTRL register's INT_LEVEL bit.
If the CMA3000 is in normal measurement mode, the INT pin is automatically cleared by reading
the acceleration output data. INT-pin data ready functionality can be disabled by setting the CTRL
register's INT_DIS bit.
If INT-pin gives an interrupt in free fall or motion detection mode, the INT_STATUS register must
be read to acknowledge and clear the interrupt.
In motion detection mode the INT_STATUS register content gives information of which XYZ
directions have exceed the trigger conditions.
See section 3.3 for CTRL and INT_STATUS register details.
2.7 Clock
The CMA3000 has an internal factory trimmed oscillator and clock generator. Internal frequencies
vary product by product.
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