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MMA865xFC Sensor Toolbox User’s Guide, Rev. 0
50
Freescale Semiconductor, Inc.
Table 15. Full-System Evaluation – Motion/FF screen
Screen
frame
Element or
frame group
Element
Description
Motion
Freefall
Note
: To
configure a
value in the
Motion
Freefall
frame, both
the Default
Motion
Settings
and Default
Freefall
Settings
checkboxe
s must first
be cleared.
Default Motion
Settings
Sets the parameters for detecting general motion to the factory default values.
Default Freefall
Settings
Sets the parameters for detecting freefall to the factory default values.
• OR
• AND
Any event meeting this criteria is run through the configured OR or AND setting,
to determine if the event is displayed.
• OR — Directs the event on the selected axes to be run through a logical OR.
• AND — Directs the events on the selected axes to be run through a logical AND. This will
trigger an event only if all of the checked events occur.
Note:
In order to select OR or AND, both the Default Motion Settings and Default Freefall
Settings checkboxes must be cleared.
• Enable X-Axis
• Enable Y-Axis
• Enable Z-Axis
Directs the device to monitor for an event along the specified axis or axes, at a g force with
an absolute value higher than that specified by the Threshold slider.
Enable Latch
Causes any interrupt triggered by an event to remain until the Status register is read.
If the Enable Latch checkbox is not enabled, then the interrupt will last only as long as the
event does, and the Status register represents the most-recent event.
Threshold
Sets the threshold for events to be detected. Events at a smaller g-force than this value are
filtered out.
• Before using the Threshold slider, click Reset.
• After using the Threshold slider, click Set to change the setting.
Debounce
Sets the amount of time that the configured conditions must be in place to trigger an
interrupt. Any event whose duration does not exceed this time will not trigger an interrupt.
• Before using the Debounce slider, click Reset.
• After using the Debounce slider, click Set to change the setting.
Set
Saves the new configuration settings after the repositioning of the Threshold and Debounce
sliders.
After changing either the Threshold or Debounce slider, click Set to register the new settings
with the device.
Reset
Resets the Threshold and Debounce sliders.
Before configuring the Threshold or Debounce sliders, click Reset to enable the new
configuration.
Decrement
Debounce
Causes the Debounce timer to be decremented, for each time that an event fails to reach
the debounce time.
Clear Debounce
Causes the timer set by the Debounce slider to reset to 0, for each time that an event fails
to reach the debounce time.
Motion or FF Event
Detected
This indicator switches from red to green if an event is triggered.