Microchip Technology MGC3140 GestIC, Руководство пользователя по настройке

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State Change Notification
The sensor has also the possibility to report some Boolean states and, according to the same principle in
the previous section, some can be ignored to minimize the number of messages.
These Boolean states are reported as part of two payload elements: 'System Data', always present in a
message, and 'Gesture Data', that is present depending on the selection of the sensor data output (see
Table 3-2 ).
The following table describes the Boolean states and to which payload element they belong to.
Table 3-3. Boolean State Descriptions
Payload Element
(1)
Flag Description
SystemInfo Noise indication The bit reports that environmental noise
has been detected.
SystemInfo DSP running The bit reports that system is running (not
sleeping).
GestureInfo Gesture in progress indication The bit reports that a gesture evaluation is
ongoing.
GestureInfo Garbage The bit de/activates the report of Garbage
gesture.
GestureInfo Hand Presence The bit reports that object is present in
sensitive region.
GestureInfo Hand Inside The bit reports that object is present and
above the sensor.
GestureInfo Hand Hold The bit reports that object is present and
not moving.
None Timestamp overflow indication De/activates the 8-bit counter (timestamp)
overflow message. This has impact on
TouchInfo
and
AirWheelInfo
messages.
Note:
1. Payload element names are those defined in the "MGC3140GestIC
®
Library Interface Description
User's Guide" (DS40001875).
3.2.3 Calibration Tuning
Baseline calibration can be caused by a number of triggers:
1. User absent time-out – where no user movement or presence is detected within the User Absent
Calibration Time-out period
(configured in the Calibration Time-out window) .
2. User present time-out – where an SD that is greater than the threshold set for presence detection
on any electrode indicates the presence of a hand which has not changed position for a specified
time while the Hold flag is triggered
(configured in the Calibration Time-out window) .
3. Touch time-out – where a touch has been detected for the Touch Calibration Time-out period
(configured in the Calibration Time-out window) .
4. Negative Value – when SD achieves invalid negative values less than -4 for 100 ms (cannot be
configured) .
MGC3140
Tuning
©
2018 Microchip Technology Inc.
User Guide
DS40002055A-page 9